I have posted this before and didn't get anything that was helpful, thought I give it another try. My 2002 360 spider have a hard starting problem when hot, the problem can be described as excessive long cracking before the engine will catch. Here are the symptoms: (1). Only happens when the engine bay is very hot, if I leave the engine lid open it will not do this. So I know it is heat related. (2). Doesn't matter what brand of gas, I have tried Costoc, Shell, Chevron, Mobil (3). Cold start no problem, barely warm no problem. (4). When the engine finally catches the RPM is quit low, stumbles a little. Doesn't have the bark from the exhaust like when it is cold. Don't think there is an issue with the battery, as the engine turns over fairly strong and fast. During the excessive cranking if I turn off the key and back on again the engine catches right away. Someone else with a spider had the same exact issue. The funny thing is I am having the same exact issue with my Porsche 911. I was thinking vapor lock, but that's more of an issue wth a carburated car. Never heard of that with a fuel injected car. Any ideas?
1) dirty air filters? 2) dirty MAF's? 3) clogged fuel filter? Since the experience is the same on the Porsche check those air filters as well.
Buy a challenge grill for the back end!!! Works wonders on engine compartment operating temps. As an aside, after a good long run, I always open the hatch anyway and let it cool off in there a bit faster, but I've never had a hot start problem. Have you asked your mechanic to look for fault codes? Seems to me this should be fixable. But again, if you don't already have one, get a challenge grill on the ass end. Dave
I suspect you have fuel pressure problem, in particular I suspect that the fuel pump/regulator is not maintaining fuel presure once turned off and the fuel is indeed boiling in the fuel rail. the 360 uses a returnless fuel system meaning there is no return line to the tank and the pressure is regulated at the pump (55psi) any vapor ofr air must travel through the injectors to purge themselves. This normally is not a problem as once the system is purged it maintains the 55psi in the system even after shut off, it may bleed down after serveral hours but at that point there is not a boiling concern possible. Just like keeping 15psi in the radiator raises the boiling point and prevents the radiator from boiling and vapor forming, 55 psi in the fuel rails performs the same function. I suggest installing a quality fuel gauge on the fuel test port and monitoring it after shutting the vehicle down. Please dont install or remove the gauge on a hot engine! Hope this helps
Im leaning towards this also. Funny though, if the fuel pressure regulators were 'leaking', then it would do it when the car was cold also or the car sat overnight. But.....I still think its fuel related somehow and teeing in a fuel pressure gauge will soon tell if there is a fuel problem.
I have a rear challenge grill MAF cleaned with special MAF cleaner Air filter very clean Several certified Ferrari factory dealer tech have not heard of the problem and have not the slightest idea No error codes Don't think it is a fuel regulator problem as I don't have an issue when car sat overnight or cold I have been told to: Ck fuel pressure Replace battery CA gas contains high concentration of ethanol, which have a tendency to boil Bad coolant temp sensor, but my coolant temp displays accurantly but I was told there are two of them I am guessing: (1). Maybe it is fuel regulator, so as it cools down the vapor turns back to liquid so when cold it starts fine (2). Electrical problem, there is a bad ground somewhere. So when it is hot there are a lot of resistance. (3). Faulty engine crank position sensor, as the fuel pump will not turn until it get a signal from the crank position sensor (sensing engine is turning), but I would have other running issues with that also FWIW, car runs perfectly once she is running.
From personal experience with the problem you describe, I bet big money on the crank position sensor. My guess is that cranking the engine helps to cool the sensor so that it starts always within 5 minutes of effort. Once running, the sensor is cooled by airflow or the ECU is more forgiving after startup. I also experienced perfect operation once the engine started. Ken
I have no doubt that the problem can be solved, just needs to be in the hands of the right tech. If you need any medical advice, I can assist you in that department.
Ken, Thanks for the reply. So does that mean if I buy two new crank position sensors and if they don't solve the problem will you pay for the sensors? LOL! Thanks
I have a feeling that would make Ken "cranky"! Here's a thought. How old are your belts? Any chance the heat affects the tensioner and throws the timing off slightly when it's warm?
Belts were replaced in 2006. If the timing were off from the heat wouldn't I have equal amount of running issues and idle while engine is hot?
I guess I should also add, that the long excessive cranking that I am referring to in only matter of difference in seconds. For example - cold starting 2-3 seconds Hot starting 5-6 seconds.
Now that to me is not a hot start problem. I was under the impression we were talking durations on hot start. I do not think that's other than somewhat normal.
Only reason why I feel that it is an issue is because my friend's 360 starts right up (1-2 seconds of cranking) regardless how hot the engine bay gets.
I would not worry about that. Many engines delay slightly when warm due to gas expansion from ambient engine heat, etc. Besides his car is not as nice as yours!!!