PTskater944

I have a '87 944 (i'm posting in the turbo forums because its more active, hopefully i can get some help faster). My car was at ImagineAuto (awesome shop by the way) and I had a new idle control valve put in because the car was idling too low. When I first started driving it home the engine was cold and the idle was good so I thought I had that problem taken care of. I stopped by my friends house, it wasn't a very far drive so when I got there the engine was just getting to operating temp. Then when I got back in the car to go home the engine was warm when I started it up and at first it wouldnt start, like the starter was turning very slowly. After a couple tries starting it I turned the key and gave it a little gas and it started up but it was idling at about 300 RPM's for a second and then just died. I finally got it started after a minute and got home. What could be the problem? It runs fine when the engines cold, but once it gets warmed up it idles at about 400-500 RPMs and goes up and down a little, also the engine shakes and shudders when idling. It runs fine once i get moving. Any help?

PTskater944

Oh and by the way, I'm pretty sure the car is running too rich. Would this make it idle bad?

Rob

I would guess your injectors are leaking fuel into the cylinders when you shut the car off. That why it will start fine when cold, but struggle when warm.

PTskater944

Thanks for the help. That makes sense, but wouldn't the extra fuel eventually get burned off and the car would idle well after a while?

Peckster

You are right.

If the problem started right after installation of the new valve, take it back to the shop and tell them it isn't working properly.

Theo951

I am leaving with this problems for 3 years now.
I have read anything, however I was not able to solve the problem.
If this low idle situation takes a minute and after that everything goes back to normal ( I need to keep the gas pedal for a minute), just connect the B and C pin at the test connector to see what happens.
My other guess is the NTC II, responsible for the Engine temperature input to ECU.
Go to clark's Garage to read more.
http://www.clarks-garage.com/
Kr
theo

PTskater944

Thanks Theo, I'm starting to think that its a bad DME relay. All of the symptoms seem to match. Clarks garage really is helpful.

Could anyone tell me how to make a jumper for the relay terminals so that I can test and see if the relay is the problem? What type of wire should I use and how should I connect them? Thanks for all the help.

Musche

Also check for air/vacuum leaks in the intake system. Sounds like when you are in open loop mode, unmetered air is getting in messing up your A/F ratio. My guess is that the shop had the intake off to replace the ICV. My car did the same thing when I forgot to tighten the clamp on the J-tube at the airflow meter. What this does is to allow unmetered air past the AFM causing mixture problems and rough idle at start up when warm. After the DME goes into close loop after 15 to 30 seconds the car would run fine. Check your runner gaskets and all the connections from the airbox back to the intake.