Causes Of Hard Starting When Engine Is Cold



The hard start when cold problem If you have a Ford vehicle and find that has a hard start when cold condition, here are the common things to check. Cold Engine Enrichment. Get a Conrader SU3-14 Cold Start Valve - Check Valves - Poor performance, or does air leak out of the intake air filter while the unit is running? This is probably the problem. 0 v8 carb hard to start My 7. Engine turns over ok, takes 10-20 seconds to start and has a rough idle until warm. To find out the compression perform a cold engine compression test. I have a '87 W124030 and if your is close to the same, I may be able to tell you where that rascal lives and his home address. Ok, I'm not totally helpless when it comes to fixing my vehicles but I'd like another opinion. Fuel injection stiction most commonly occurs when a cold engine is started. 8 with 150,000 miles. An indication of piston slap is a decrease in noise as the engine warms up. There is a problem…. Turns out that getting the right amount of oil in this unit is NOT easy! To do it properly, you need to run it hard for 20 minutes, then stop and check the levels. How to Start a Cold Engine. if one glow plug is not working, it will shorten the cycling time and make starting hard. The wierd thing is that the day after I run it, it will crank up right away with no problems. Hard starting can be caused by the following: 1. Popular Causes Of Car Engine Vibration 1# Engine Vibration Cause: The Crankshaft Damper Some engine problems may cause your car vibration. can cause hard starting, hesitation and even activate a "check engine" light. Let the engine idle for about 5 minutes with the throttle fully closed. Periodically my truck will not start when cold or damp outside. This can cause a low rpm miss/instability, white smoke, hard starting, or low power. cold engine start problems. Remove the radiator cap and fill it to the recommended level with a 50/50 mixture of antifreeze and water. Before you pay for an expensive repair on your hard-to-start Briggs & Stratton lawn mower, check out this helpful guide on diagnosing and fixing engine problems. Hard starting can be caused by the following: 1. To see how poorly the truck could handle cold starts, it was parked outside overnight, in 20-degree weather. Also, below a certain engine temperature, the engine management system automatically initiated a fast idle sequence. why is my car hard to start when cold but otherwise runs fine? Its a 1998 model SB Barina, (Corsa B) with an opel engine. Once you know the engine will start and run, I would turn it off and change the oil and filter. Responds readily to the throttle when cold. Over the past years this is what's been serviced: remanufactured engine, rebuilt transmission, egr valve, drive shaft, battery, brakes, tires, water pump, catalytic converter, muffler, fuel filter, and thermostat. When I crank it up, open the throttle about 1/4 of the way, pull out the compression release, crank it till it is turning over for about 5 secs or so, and shove in the compression. If it is a cold start, they run certain tests. Engine Performance problem 6 cyl Two Wheel Drive Automatic 210000 miles I've a 99 Eddie Bauer, 4. Hold the engine speed at 3,000 rpm (min) without load (in Park or neutral) until the radiator fan comes on, or until the engine coolant temperature reaches 90 °C (194 °F). An older diesel citroen a friend drove took about 30 seconds of heating this way before it was worth even trying to actually start. Disconnect the Engine Oil Temp (EOT) sensor at the rear of the oil reservoir. my 1991 mitsubishi mighty-max 4x4 V6 truck tends to start with difficulty (several cranks) when the engine is hot, meaning after it reaches operating temperature and i turn it off, it will start with difficulty. Press the throttle trigger quickly too. When there’s an imbalance of these elements, the motor may fuel with an excess amount of fuel. There may be old or bad fuel in the carburetor float bowl. After starting. Make sure the choke is on if you are starting from cold, and immediately push choke lever to the warm start position when the engine starts to run. IP: Logged Message: a leaky injector can also cause long crank times. 3L engine in your Chevy is like like that. Black diesel engine smoke when starting on cold start, or while accelerating hard, is not uncommon with older cars. I wouldn't personally say that it is related to cold starting, because I live in Las Vegas. The other sensor tells the computer that it is a 'cold start' and changes the gas delivery - basically I think this means it delivers more gas by keeping the injectors open for a longer time. My question (and I suspect a lot of other readers would like to know, too): What is the reason that higher octane. Indeed, the main duty of this component is to decrease vibration. I have owned a lot of cars but this engine on cold start is by far the noisiest motor ever. An engine fitted with a priming bulb type choke that's hard to start hot, and is smokey - will likely need the carburetor to be cleaned or replaced. There’s a myth that diesel doesn’t burn, diesel does burn – one of the major differences between diesel and petrol is the way the two fuels burn. Hot Starting Problems (The car starts OK when cold!) Hot starting problems have five principal causes: Starter Tight Engine Engine Malfunction Fuel problems Electrical The cause can be isolated using the guide at the right. yes the cold weather will cause this. The Ecm is working when cold or else your truck wouldn't be running. It was because of hard starting in cold weather, and the need for cleaner emissions, that carburetors were replaced in the 1980s with computerized fuel-injection systems. if one glow plug is not working, it will shorten the cycling time and make starting hard. 0i with 62,000 miles. It is by far the most often asked question that we have received from our customers over the years. If you are going to try this you need to first check that when you do it - fuel does not overflow out of the fuel system into the engine compartment onto the ground - with the inherent danger of a fuel fire. Sometimes, the engine will start to catch but wont have enough to sustain idle. Hard starting is defined as requiring extended cranking. Between the Hemi ticking and whats sounds like my lifter clanking (which only happens some times) I have to say it makes me question how reliable this motor will be. Why do diesel engines have problems starting in cold weather?. Chokes are usually automatic but can be manual on some engines. On a hot day this can be as much as 20 minutes. Causes of engine management light. Fuel pressure should hold all day, but I'm guessing that's a symptom, not the cause of your hard start, since pumping it up doesn't immediately cure it. The Problem: If I cut it off warm then try to restart it like 30 min later it is very hard to start (like after a lunch break and such). I took it back and the same Nissan dealership and they changed the fuel pump and filter (both visits came to $650). A simple check is to remove the rad cap (engine cold) and start the car - if you see coolant actively moving, the thermostat is stuck open and should be replaced. Some engines may blow up after starting them that have sat for 2 years in nice dry storage. Magnum ReD 2,373,735 views. However if I spray starting fluid in the TB while cranking it will start. cold engine start problems. 1) Low fuel supply pressure or air getting in the fuel For basic fuel supply system diagnostics; please reference TSB 14-07-96. If it only starts hard in cold weather, check the coolant temp sensor. Some common reasons for motor vehicle stalls include: An empty gas tank; A fuel mixture that isn't rich enough (this is usually the cause of cold stalling and intermittent stalling) A faulty fuel pump, alternator or EGR valve. If you move the control to the furthest (fastest) position the engine will start but starts reving like mad and you have to quickly lower the speed. I've found that the type with the rubberized palm/finger area and the open fabric backs work the best. This can cause a low rpm miss/instability, white smoke, hard starting, or low power. No code is coming out. This makes the combustion of fuel hard for the car and therefore some actions have to be done to get rid- off the situation. During engine start be alert for carburetor flooding or the need for excessive leaning. Seasonal gasoline blends can also cause starting issues, especially where there is a significant temperature shift between the seasons. If the diaphragm is ruptured inside the regulator, fuel will leak into the intake manifold and cause a hard starting condition. Engine Not To Start When Hot. Runs worse as it warms up; Hard starting when hot ; Ragged idle …due to “loading up” of unburnt fuel ; Idle that tends toward lower rpms than expected based on the setting of the curb idle screw. There are 2 main reasons why your car may develop ‘hot-starting’ issues: Your engine may be suffering from low compression. This is due to cold and wet weather and the fact that the engine is cold. Low fuel pressure or air entering the fuel system. I have just learned to live with it and accept is as awesome Nissan engineering. How To Diagnose A Hard Starting Hot Engine By: Bill Tichenor 12/02/2009 < Back to Blog Home Holley offers tips on diagnosing hard starting engines that are already at proper operating temperatures. So I was thinking why is this a factor. What happens when initially starting a 2 stroke with leaking rings is when the piston is going up it creates a low in the crankcase drawing air and fuel into it. With this problem, the engine will become more difficult to start during periods of cooler or cold weather. Re: Hard to start after warm-up Relax, that's not unusual, and it's not a sign of impending doom. I was running a sbc 400 with double hump heads and had the same problem. diesel engine hard start when hot magandang hapon mga sir. Hard Starting. A simple trick is to use the glow plugs a little more. First, the oil in the crankcase thickens. Finding out what is wrong with your car by feel, smell, look, and sound. Because starting a radial (or most any other reciprocating engine) required the operator to have some "feel" for the machinery, something severely lacking amongst most of those those weaned on Nintendos. As a result, starting the engine may prove difficult due to the wet spark plugs. Greetings! I am in desperate need of help. My first thought was that it could be the glow plugs, however after some reading, I believe that glow plugs are only required when temperatures are approaching freezing, which isn't the case here in the UK at the moment. cold engine start problems. This would cause. Hot Starting Problems (The car starts OK when cold!) Hot starting problems have five principal causes: Starter Tight Engine Engine Malfunction Fuel problems Electrical The cause can be isolated using the guide at the right. Starter circuit problems, which include wiring, connections, ignition switch, safety neutral switch or clutch switch, and starter relay. Hard starting and rough running 1991 500sl w129 I was hoping someone here could help. When temperatures drop to freezing, or when it's cold enough that windshields will frost over, the oil needs to warm up before it can move smoothly throughout the car. "The lady across the street has Club Car gas golf cart. To start a car in freezing cold winter weather, start by shutting all of the doors and turning off any accessories, like the heater, radio, and lights. on my 89 740 wagon non turbo i have been having problems starting it since it started getting cold out someone told me that there is a cold start valve and that most likely it was the problem replaced the cold start valve and it didn't make a difference and even started back firing so if any ideas let me know cause i dont know much about volvo. of Energy Argonne National Laboratory concludes : "Idling for more than 10 seconds uses more fuel and emits more CO 2 than engine restarting". what should i tackle first?. I have just learned to live with it and accept is as awesome Nissan engineering. ) or if it was actually computer controlled and a design feature of the car. Re: Engine wont start when hot!!! help! well i didnt see the post about not using header wrap, but my friend is cheap and doesnt want to buy a starter, but the wrap seemed to have work, now the car will fire when its hot but it still seems like it is struggling to start, maybe one day he will listen to me and get a starter but for now its. Replacing the starter is the most common repair for these symptoms. efi spares trade tips. Once this bend in the hose rots and causes a vacuum leak many performance problems crop up – loping engine, lean miss, stalling, high idle speeds, hesitation, power loss, and the PO171 & PO174 code combo. Starter solenoid faulty. Storing equipment with untreated fuel in the tank for more than 60 days is risky, as aging gasoline can cause havoc within the carburetor and other fuel system components. yes the cold weather will cause this. Starter circuit problems, which include wiring, connections, ignition switch, safety neutral switch or clutch switch, and starter relay. (Operator's right). Chances are that the engine's problem lies in one of th. When key in the ignition or on start yields cranking. * Idle control valve - The idle control valve may be faulty and not properly bringing the idle speed up when the engine is cold. Once I learned how the system worked, the starting of the old girl became nearly effortless. Oil and other car fluids become thicker and more sluggish in cold weather, which makes the battery to work even harder. Found out that the 2009 has the same starting system as the newer ones with push to start button. if not the fuel is going somewhere. Some engines will start right up and be perfect after not being started for 25 years and setting outside in a puddle. When we start the vehicle, the drive cycle begins. Compression should be between 20 to 35 bars or 300 to 500 PSI. 6 hard starting. And the delivery systems that move these fluids like fuel and oil pumps, hoses and filters can all cause problems when starting an old engine. The Top 5 Causes of a Cranking Car That Won't Start Most of the time, the cause of a cranking car that won't start is very simple and affordable to fix. If that air is warmer than the block, it'll condense water on the cold surfaces of the engine. How to fix a Diesel that’s hard to Start Cold? Cold weather starting becomes increasingly more difficult as engine deposits build up over time. Whenever you start the engine in cold condition,its just fires up right away. By using modern measurement and analysis methods (engine or vehicle cold test bench, noise prediction by CSL and DoE guided measurement programs),. If the engine does not start, allow a 60 second cool down period between starting. Hard starting can sometimes be caused by a glow plug module that fails to turn the glow plugs on or doesn't keep the plugs on long enough when the weather is cold. Generally when it happens it will start with misfire codes sporadically when the car is cold(or has been sitting for a while). The battery, the oil and fluids, and even the rubber are all susceptible to cold temperatures and can potentially fail because the weather is freezing. During acceleration this misfire gets so extreme it can cause the engine to stall. "Can an open or not responding O2 sensor cause this hard starting problem after the engine is hot?" No, because during low RPM cranking, the ECM is not using the o2 sensors at all. Starts too easily when cold – requiring little or no choke. Re: Difficulty Starting 2 Cycle Engine? It could be a little bit of every thing pointed out above. This can cause it to be harder to burn, thus causing your engine not to start. Holley offers some tips on how to diagnose and fix a hard starting engine. If the engine and crankcase oil isn't warm, it takes a strong battery to crank it, and if the fuel is cold, it takes healthy glow plugs to start the combustion. When temperatures drop to freezing, or when it's cold enough that windshields will frost over, the oil needs to warm up before it can move smoothly throughout the car. Using our website search box for both tech help and products, enter the words of the solution. But there's no need to rebuild or replace the carburetor if all that's needed is a simple adjustment or cleaning of the choke mechanism and linkage. Worn cylinder and/or rings. From Cold Start, car has trouble holding idle until warm. 8 with 150,000 miles. Make sure the choke is on if you are starting from cold, and immediately push choke lever to the warm start position when the engine starts to run. Good day, My Nissan X Trail hard starts while making errands however, when I start the car first thing in the morning it starts in one or two efforts. Its fuel injected. Very often this could be caused by a low battery or poor connection between the battery and starter. Mechanics often use a known-good mass air flow sensor to test if the engine starts. Over time, some of the ingredients in the fuel may evaporate, leaving behind a thicker, stickier substance. I`ve got a 19 HP Kohler engine in my Ariens GT 19 tractor. If the cold-start timer switch wasn't working properly, it would do the same thing, or it could possibly cause the cold start injector to fire all the time, making. I have to put my two cents worth in. Compression should be between 20 to 35 bars or 300 to 500 PSI. I have a 2008 X5 3. Problem: Engine won’t start when its really cold. 12 Choke Off Remove these two bolts and remove push on wire connector. Another reason why you may have an engine, which is hard to start while hot, is that it may be due to seasonal weather as refiners change from one fuel blend to another. It also depends how many miles you drive and whether the battery is charging fully after starting and driving with headlights on. RE: Hard starting when cold. When cold you have to take air cleaner off and place hand over top to get to start. After that, see if jumping to a second battery allows the car to start easier. I have to pump the gas paddle and one by one the pistons catch and it starts. My 73 (350 4bbl Quadrajet) is hard to start after it sits for more than a couple of days. diesels are a problem to start if glow plugs are not working properly. This can cause a low rpm miss/instability, white smoke, hard starting, or low power. A simple trick is to use the glow plugs a little more. It will run rough for a few minutes and check engine light is on. Now the car was running pretty good in general, but the cold start/idle issue was buggin me because I figured it should be better than it was. The popping noise tells you something isn't right. The real deal is all about emissions. The Problem: If I cut it off warm then try to restart it like 30 min later it is very hard to start (like after a lunch break and such). This is a general guide which will list symptoms for 944 starting and running problems and common causes of those problems. To compound the problem, the thermo-time switch has now timed out, and must cool before it will supply the necessary ground to the cold start valve to get the extra fuel to the engine for a start. If you have a 2009-2010 Toyota Corolla with a brief engine rattle noise on cold start up then you will want to replace the intake VVT-i gear per Technical Service Bulletin 0087-09. Is this something we should be concerned about and take back to the dealer for repair. If the engine overheats a few minutes after start up, the most probable cause is a defective thermostat. Timing, spark, fuel. I had the mechanic look at the motor and he said it's just a hard starting engine. Diesel won’t start when it’s cold – could be Glow Plugs Cold weather, especially extreme cold weather, causes havoc with your diesel engine ignition system. This causes the fuel to be more burdensome to burn due to the fact that it is burnt when it is evaporated. This is normal, the engine will run smoother as engine temperature increases. 0 liters, runs fine when it’s cold. Gasoline won’t do because a spark can ignite gasoline fumes and cause an explosion or a fire. When I crank it up, open the throttle about 1/4 of the way, pull out the compression release, crank it till it is turning over for about 5 secs or so, and shove in the compression. "Can an open or not responding O2 sensor cause this hard starting problem after the engine is hot?" No, because during low RPM cranking, the ECM is not using the o2 sensors at all. Common Possible Causes. Buildup on the blade, bore or IAC valve will make it hard to start. P0101 MAF Circuit Range/Performance Technical Description. And yes, you can drive gas Volvo with slight engine defect but diesel Volvo will not forgive any lack of precise and in time service procedure. "Can an open or not responding O2 sensor cause this hard starting problem after the engine is hot?" No, because during low RPM cranking, the ECM is not using the o2 sensors at all. Once this bend in the hose rots and causes a vacuum leak many performance problems crop up – loping engine, lean miss, stalling, high idle speeds, hesitation, power loss, and the PO171 & PO174 code combo. Hard starting can be caused by a choke that fails to close and causes a rich fuel mixture when the engine is cold. Hot engines can be tough to start, and many people do not know how to deal with this situation when it occurs to their cars. The battery, the oil and fluids, and even the rubber are all susceptible to cold temperatures and can potentially fail because the weather is freezing. DIAGNOSIS You should start your diagnosis with a visual inspection of the cooling system. As the name implies, automatic stop/start shuts off the engine instead of it idling at a stop and then rapidly restarts the engine when you want to drive away. Don’t crank and crank and crank a hard starting motor until you fry your starter. Even 1 or 2 lbs. This happens winter or summer. Do you have a Check Engine Light on? You may have some codes that can be read - anyway, if the last tuneup included a fuel filter, you are about due. Periodically my truck will not start when cold or damp outside. The automatic choke may be defective or incorrectly adjusted. We just had our first cold blast and I noticed hard starting a couple times in the past weeks. If one of these three components are not present or not functioning correctly, the engine will not run. Your engine is most at risk from damage when cold, so putting undue stress on it by high revving will exponentially increase the damage done. run the truck with a fuel pressure gauge on it. First, the oil in the crankcase thickens. A cold start situation is commonplace, as weather conditions in most climates will naturally be at a lower temperature than the typical operating temperature of an engine. In fact, 3 household brands have already been fined. by Kyle McFadden. The hard starting problems of diesel engines in below zero / freezing temperatures are caused by two factors. If the secondary chain tension unloads at the beginning of cranking the noise will be worse. Condition: A hard pedal or lack of power assist in cold weather (below freezing) at initial start up when the brake pedal is depressed. Every morning when i started the bike,it start with one click. Difficult Cold Start Problem : Several things could be causing difficult cold starts for your 6. Should be a good solid 12 volts from your battery, 14. Diesel engines are equipped with things called glowplugs. Cold stalling problems are the most common because the engine needs a richer fuel mixture to maintain idle speed until it warms up. I noticed that the other people complaining in this digest were >325's but I think we share the same engine. If the engine is warm or has been running within 2 hours or less, it will fire right up. Be very careful of course, to stay away from any moving parts. , Hard To Start, Engine Cold, Engine Compartment. After it started, engine would stumble when accelerating from a stop. im seeing alot of complaints about this issue on vehicles fitted with the early 1 ad & 2ad 2. Starting a TDI in Extremely Cold Weather Although VW has made great strides in making the TDI suitable for very cold climates, the nature of a diesel is such that it will still need more cranking power to fire. If hard starting was engine barely or doesn't turn over, it would mean two things, your battery should be back up to full and with surface charge reserve of 14V (2 volts over full charge 12. - Bruce Cunningham, '53 XK120 OTS. Low engine compression will result in insufficient heat being generated to ignite the fuel and cause hard starting. If you have no injector pulse, spark or fuel pump supply - check you have 12volts to these items. However, your problem doesn't sound like a cold-start injector problem usually if you had a bad or malfunctioning cold-start injector, the truck would be hard to start when cold. If your car has a push button start system, read this guide: No-start issues with the push-button start system. Here is a common cold starting problem for the 2 stroke carb engines. Either the distributor moved or you have a different problem. 0L with 161,000 miles. Full Answer. This is due to cold and wet weather and the fact that the engine is cold. Also, my fuel mileage has dropped from 8 to 7. Cold weather hit, scooter won't start. Some of the problems relate to vacuum leaks & connections, ignition plugs, wires, egr valve and engine timing. Engine cranks, catches but either barely idles and stops or revs really high and stops. Note: See also TSB 18-06-98 - Hard starting diagnosis. It's usually harmless, although it might not feel that way. So, if the oil level gets too low, the fuel line may freeze because of the condensation, preventing the fuel distribution to the engine. Release the switch as soon as the engine starts. efi spares trade tips. Cold starting problems - diesel engine 24th Nov 10 at 3:15 PM #1 It's a 1999 laguna 1. It acts like there is no fuel in the carburetor and needs to crank for several (4+) tries before it starts. Then just start your taxi, and by the time you reach the run up area, your oil should be warm enough. However it is getting more difficult to start when cold. Hard starting is a nuisance you shouldn't have to put up with. Oil and other car fluids become thicker and more sluggish in cold weather, which forces the battery to work even harder. My wife's 2010 chevy tahoe is so quiet on start up and doesn't rev at 1500rpm when cold. Combat the Effects of Cold Temperatures. However, your problem doesn't sound like a cold-start injector problem usually if you had a bad or malfunctioning cold-start injector, the truck would be hard to start when cold. A final point, CHANGE YOUR OIL OFTEN. Troubleshooting - Engine turns over but will not start (4 stroke) The choke is used to limit the amount of incoming air into the engine to assist with cold starts. Another reason by which a cold engine might have problems to start is caused by the fact that oil becomes much thicker in cold than the way it is in hot. Gasoline won’t do because a spark can ignite gasoline fumes and cause an explosion or a fire. Especially, if you park outdoors in a cold night, you may notice the car hard to start in the morning. Most of the reasons by which a hot engine would be hard to start are based on problems related to the fuel. I have a 2005 Nissan Sentra S 1. If the engine is new, pull the starter grip several times first to prime the fuel line. The disturbing diesel knocking is caused by hard combustion, as explained earlier. 1 cause of a no-start. You can also, when the engine is cold, use the metal end of the screwdriver and tap the sheet metal parts around the engine bay. 1) Choke not closing properly. Engine cranks, catches but either barely idles and stops or revs really high and stops. The engine is stock except for an HEI distributor (GM). Check the valve clearance. Persisting with a slow-cranking engine can cause over-enrichment, resulting in wet plugs and no start until the plugs are removed and cleaned. In order for an engine to start and run cold, it requires more fuel than when it is hot. Oil, like any other liquid changes its consistency when it is exposed to very low temperatures as well as it changes back when it is in a very hot weather, and this might cause oil to have. My wife's 2010 chevy tahoe is so quiet on start up and doesn't rev at 1500rpm when cold. There are a number of potential causes for this problem. That timing won't cause the engine to not start. Common Possible Causes. cold engine start problems. With idle set at 1000 RPM, the engine should start with no throttle. And yes, you can drive gas Volvo with slight engine defect but diesel Volvo will not forgive any lack of precise and in time service procedure. The second is that the car's ECM fails to transition automatically from cold to warm operating parameters. Level the engine after it is in the water. An example may be a "cold start. Hard Starting. SYMPTOM SUMMARY The engine idles too high. Get a couple of weak pops, then nothing, after about 20 or so pu. Also prior to getting cold the Pathy did the hard start deal on me once now that I am thinking back here are the symptoms if anyone can advise. What with the viewing,. Here is the history: Got a check engine light and Hard to start - Weird problem, need help - Toyota 4Runner Forum - Largest 4Runner Forum. There are a number of issues that will make a car hard to start. Children younger than 6 are at greatest risk of colds, but healthy adults can also expect to have two or three colds annually. Chances are that the engine's problem lies in one of th. Pull-Starting an Engine that's Hard to Start: When working on small engines without electric starters, you will likely have to pull on the rope a bit more than you'd like. Do you have a Check Engine Light on? You may have some codes that can be read - anyway, if the last tuneup included a fuel filter, you are about due. 6L engine and Automatic transmission. T ools / M aterials (See Below for Applicability): Technician equipment (like an engine analyzer, etc. Am alibor pius, a marine engineering student, i wish to become a mariner since when i was in primary school, i saw alot of boat and ship passing through our river and i said am gonna be a sailor in time to come, in year 2009 my uncle ask me if i which to become am engineer, i was so happy of which i. I just replaced my crank/cam sensor with the new revised ones after the they failed and mine still can be hard to start too. The crankcase oil is cold and stiff. Heat related failure of the injector pump's run solenoid is common. Attempting to start a warm engine with the choke on will cause excessive fuel to enter the cylinder and flood the engine. Cured symptoms not much different from yours. 5L diesels, there have been reports of heat from a still-warm engine causing the 125-degree inhibit switch inside the controller to shut off making the engine hard to. The PCM checks to see if this is a cold start or a restart. cold engine, however, starts very easily (first crank). Scooter Won't Start, Hard Starting, Rough Idle, or Stalling Introduction Inability or difficulty in starting the scooter, rough idling and stalling can be indicative of a variety of issues and causes. On an older engine, this is often not enough to start the engine. The first start of the day would go just fine, but the rest would turn over and over rapidly until I pumped the gas pedal. The offender was the throttle air bypass valve. It's similar to a choke on a lawn mower. Magnum ReD 2,373,735 views. A vacuum leak on a fuel injected engine will cause high idle. Smoking pretty good while cranking, so fuel is getting to the engine. Common Possible Causes. The problem is, after the motor gets good and hot and we stop for an extended time for a swim break then the motor will crank but not run. Using engine starting fluid is a very effective method to starting both gas and diesel engines in sub zero temperature. The 450's need a bigger jet. Also prior to getting cold the Pathy did the hard start deal on me once now that I am thinking back here are the symptoms if anyone can advise. The same concept applies to gasoline. common causes of rough idle, hesitation, stalling and hard starting. Then just start your taxi, and by the time you reach the run up area, your oil should be warm enough. 1) Low fuel supply pressure or air getting in the fuel For basic fuel supply system diagnostics; please reference TSB 14-07-96. Dear Doctor: I own a 2006 Chevy Equinox. Too much fuel is delivered, resulting in unburned fuel in the exhaust. Also, below a certain engine temperature, the engine management system automatically initiated a fast idle sequence. If 4 hours or more have passed since I turned it off (cold engine), the starting problems are there. Even 1 or 2 lbs. Condition: A hard pedal or lack of power assist in cold weather (below freezing) at initial start up when the brake pedal is depressed. the gauge should be still the same psi. or just a “gummed up” carb can cause all sorts of no-start problems. Some common reasons for motor vehicle stalls include: An empty gas tank; A fuel mixture that isn't rich enough (this is usually the cause of cold stalling and intermittent stalling) A faulty fuel pump, alternator or EGR valve.