Engine wont start when hot

[Yoni_d]

Hi All

I have this weird problem.
When the car is cold, the engine starts right away with no problems.
When it is hot and I shut the engine down, I can not start it again.
I have to wait about 5 minutes and then it starts - it doesn't start as easy as when it is cold but it starts after a few seconds.
I have noticed that if I shut down the engine when it is hot just when I park the car (I dont let the engine to work in idle more then a few second) then it might start again. But, when I keep it idling for a few minutes before I shut it down - it wont start.

Can it be the Accumulator? how can I test it?
Fuel pressure and everything seems to be good.

Thanks.

[DPW928]

Yoni,

It sounds like you have a fuel pressure leakdown. This can be caused by a bad accumulator, bad check valve on the primary fuel pump, bad relief valve in the fuel distributor or leaking injectors. When it does start, after waiting, does it miss or blow black smoke? If it does that's an indication your injectors are leaking into the combustion chamber. This can normally be fixed by running two or three treatments using Techron or Gumout type fuel cleaners. The accumulator can be checked by removing the plug (or return line if equipped) on the back and checking for fuel. The relief valve in the distributor can be checked by removing it and checking the o rings to make sure they aren't broken or cut. If all those check out OK the check valve on the primary pump is probably the culprit. There are two types of pumps. The early cis cars normally came with a long neck pump the had an internal check valve then later pumps were equipped with an external valve. On the later, the valve can be replaced but the earlier requires replacement of the pump if the valve is bad.

[928SROCK]

undo the gas cap then put your foot to the floor on the gas pedal and turn the key then put the gas cap on. Temporary fix to a immediate problems.

[Yoni_d]

Thanks for the information.
After waiting a few minutes, the engine starts after a few seconds...no black smoke and during those few seconds it tries to start...the feeling is that it is flooded.
After 30-60 minutes, it starts on the spot.

The accumulator check...mmm...didnt quit understand that check. where is that plug that you wrote I have to remove?
What do you mean by checking for fuel? Do I have to do it when the engine is cold and check if there is fuel or not?

[DPW928]

The accumulator has a diaphram inside to hold and stabilize fuel pressure. If the diaphram leaks it will cause a hard warm start. On its small end (opposite of the end with inlet and outlets lines) there will either be a hex plug or a single fuel line to return leaking fuel to the tank. If you remove the plug/return line and there is fuel present, the diaphram is leaking and the accumulator needs replaced.

[Yoni_d]

Thanks, now I understood!

[Georgian]

Yoni_d

I have EXACTLY the same problem on my WV Jetta 2002 and still have no idea how to fix it

I'll be very thankful if you please tell me how you have solved this problem on your car years ago?

Thanks in advance!

[leonl]

Sorry to bring up an old post. I have similar issue and so far I have new set of injectors, fuel accumulator and battery. It is still hard to start after the engine runs warm. First start in the morning with no problem. Let it sit for a while and it cranks right up. Anything else I could try? Thanks.

[DPW928]

Try unplugging the cold start valve before attempting the warm start. If it starts OK you probably have a defective thermal time switch.