250tony

Hi, just purchased a 89 S4 and it has some issues. When the car is cold, it starts but I have to keep pumping the throttle to keep it running. After a few minutes at 2500 rpm's it smooths out and runs great but it will not idle, either warm or cold. Lastly, not sure if it connected but the cooling fans will not come on. They only come on when a/c is running.
Fuel pressure is within specs, new pump and filter. Smoked tested with a few vacuum leaks,fixed and lastly I found the grounds cleaned them.
Please can any one give me a direction to go?
Thank you.

Landseer

Do a complete intake refresh and CE panel remove / clean / re-fuse.

Search "dwayne's garage" for an 87 intake refresh pictorial guide that will show you the idle position valve, vac lines and throttle position sensor and hall sensors that will likely need to be addressed

Pictures will help, us dial in further, as will maint. records.


Fan controller is another searchable --- can be an issue --- thread exists for electronic rebuild of circuit, too.

Mrmerlin

check the flex plate before you do any more work,
also get a reading of what the crank end play is

SteveG

Idle problems are usu vacuum related, but you fixed that. Could be Idle Control Valve. And/or Temp II. You found all the grounds? See New Visitor thread, #33.

dr bob

Dwayne's write-up includes a DIY pressure test setup that will get you on the way to finding intake leaks and also oil system leaks that are ultimately vacuum leaks. Home Depot components and such, connects to the MAF where the air cleaner is now. A little air pressure and you will find all the leaks. Once the system is proven tight, the next step will look at fuel regulators and dampers for fuel leakthrough. That starts with a MitiVac or similar, then a fuel pressure gauge to do a macro test for injector leaks.

If the car has the original LH fuel controller, you may want to swap it into a known good car to verify it's still ok.

davek9

+ 1 on the Fuel system check

James Bailey

Ok so you have to rev it to 2,500 rpm to keep it running or it stalls out......I would check the vacuum lines on the fuel press regulators and front fuel damper for a fuel leak dumping raw gas into the intake...When you "pump" the gas pedal all it does is ADD more air. So most likely you have too much fuel for it to idle.

Mongo

I've said this many times on other threads, but choose to say it again..


Does it crank slow when warm after it stalls????

250tony

Thanks to everybody. This is my first post. Your commits are very helpful. I now have some direction and I will be off running things down.
Tony

Randy V

You didn't answer the question.

250tony

the car doesn't crank slow when it warms up, will not idle either cold or hot.