carrie w

I have a 1987 5000cs turbo with hot start problems.It is what seems to be the classic story of starting fine when cold then once it gets warm it takes about a hour to start again.I cleaned and replaced breather hoses-no luck. My mechanic (seems knowledgable w/older audis) said I have a fuel injector leaking and need to replace them. Also, I only started having this problem when summer arrived and I have tried techron and krex.
Any advice or insight? -Thankyou

sweett tt

I just had that problem about a month ago. And it was the fuel check valve on the fuel pump. you can check the injectors by removing the spark plug and looking down into the cylinders to see if they are wet, but i doubt it. What happens is the check valve lets the gas back into the tank and causes a vapor lock in the lines especially when it is hot. At the point that you have to remove the fuel pump you might consider changing that too if it needs it.

Tom Faust

Hard starting problems are almost always a loss of fuel pressure. Could be the injectors, but I tend to doubt it. Try this, switch ignition on and wait ten seconds before cranking. If that resolves the problem,at least you know it is fuelpressure. I suppose you could pop the injectors and sit each in a glass bottle amd watch them.

SteveAngry

1. Leaking fuel injectors...

2. Check valve on the fuel pump...

3. Cam position sensor...very rare.

Steve
Michigan

carrie w

I tried switching ignition on (a few times)-Nothing.
So could it mean fuel injectors?
thanks,
Carrie

Tom Faust

If the pump couldn't build pressure, your injectors would have to be leaking pretty rapidly. It manages to keep up pressure at 80 mph, and the injectors are squirting a lot of fuel. Any other symptoms? Poor mileage? Flat spots? I wonder if the pump is just old? After running for a while it heats up and malfunctions.