help needed...my 1990 g rs turbo wont start when warm..been through a few yhings but no joy.its gettin fuel so looks like an electrical fault also someone said it might be head gasket..any help would be much appreciated..cheers

 

I persume its turning over?

You say you have fuel, has it got a spark?

 

yeah its got a spark.it drives fine until you stop and go to start it again..it just keeps turnin over

 

not the starter motor knackered is it? heat kills these reguarly

 

The car wouldn't turn over if it was the starter.

 

Starts fine when it's cold but won't if it's warm and standing aroung for more than a few minutes?

Theres a valve on the fuel pump so that the petrol pressure can't go back into the tank. Was also a problem on my XR2 K-Jet because I didn't know it and used a fuel pump without the valve.

 

Stick this in GD with attention of tuners. Not everyone checks in this forum who may be able to help.

 

sticky aux air device ?

 

As XR2 said, i had the same problem, a nightmare fault when the car is hot. Mine would take anything up to 5 minutes of solid cranking before it would start and all because of a poxy one way valve

You need to check if the fuel pressure is being held overnight....

 

Why does he need to do that? He's already said it starts fine until you stop again then it won't go...not overnight.

 

To see if its losing the fuel pressure.

The pressure should be retained no matter how long its sat, i tend to leave the car over night and check then when its cold etc

 

Could he not do that after it's been for a run tho and before he re-starts it ?

 

Theoretically yes, but the reason i like to leave it overnight is because it gives it a good chance to leak and lose pressure IF its going to.

If hes just turned it off for a couple of minutes it may have lost enough pressure to effect re-starting, but still retain enough pressure to indicate otherwise when you push the flap down

if that makes sense to you

 

Yup.
But it doesn't have to make sense to me

 

Yes it does, you can do the dirty work now and ill just sit back and relax

 

What dirty work? He doesn't live near me.....I won't be doing it.

 

could it be anything to do with the spark plugs

 

How you describe it - the problem is the one way valve on your fuel pump.

When the engine is hot, everything under the bonnet is hot too. Fuel lines are constantly cooled by fresh fuel from the tank. If you turn the car off, the fuel lines will get very warm. The fuel is getting air bubbles. If your one way valve is not working these bubbles will be getting very big and push fuel back into the tank. You're not able to start for a long time because wehn the pump is making pressure the bubbles are compressed but won't push the fuel behind them because they "suck" the pressure when they are compressed.

When you leave the car for a few hours everything will cool down, the air bubbles will vanish and you can start your car without any problems.