gudmundur

Hi

We have had an issue with our 93 964 C4 for a while.
It has a TPC supercharger and it does not idle at all.
Always dies as soon as we let go of th throttle.

Is there any way that we can run System adaptation to get the car to idle at all ?

We have btw changed out alot of parts trying to solve this issue, like DME relay, coil threads, ISV, O2 sensor, Airflow sensor but without any luck

Any ideas would be really appreciated

regards
Gudmundur

jimq

try the hammer or scantool. Might help if you say where you are located also.

Akerlie

From the name it looks like he is in Iceland

gudmundur

Yup you are correct sir .. I am in Iceland

We dont have access to a Hammer but we already started looking at building a Scantool interface.

For those of you that have used Scantool, doesnt the engine need to be running to finish the System Adaptation process like on PST2 ?

gudmundur

After loads of work, the solution was to adjust the screw that moves the throttle plate just 1mm or so.
Not the one that adjust the cable and everything else, since that would'nt leave the idle switch closed.
But the one besides it

btw we were able to get a Hammer on a loan today but it never worked for us, just said that system adaptation was not possible, the car was though up to running temp, off the throttle and idling

F2 Iceland

false alarm

gudmundur

Yeh sorry to say the problem started again just a few hours later.

Oracle

I guess you triple checked.. but are you positive there are no leaks?
Disconnect the battery for 1/2 hour, next time you drive the car for 1/2 hour (IIRC) after warmup the adaptation is done automatically. I can't remember exactly :-(

DarrylH

System adaptation should be possible with the Bosch tester if the engine is at operating temp, all "consumers" like the a/c, headlamps and fans etc are off, and the idle switch contact is closed. It will not work if that switch is defective or open.

However, my tester always starts the process with a message that says the system adaptation is not possible. Then if I do nothing, just wait, anywhere up to a minute or so later the system adaptation process will start and run to completion successfully. I have no idea why it has that pause before working. If you didn't wait a while when the message first appears that says it's not possible, it may be worth trying again. If you waited enough time and it still didn't work, you may have a problem as yet undiagnosed.

Is the car storing any fault codes? Does it have a catalytic converter? An O2 sensor? The changes made by the supercharger's presence throw a wrench into the whole thing, I'd guess, although I know nothing of superchargers.

In my experience, the reset done by driving after a battery disconnect is not the same. It only addresses one of two elements of the adaptation process, and my car never idles correctly after a battery disconnect until the adaptation is done with the Hammer. YMMV.

sml

+1


Tried the battery disconnection technique 20-30 times.
Today I drove to the mechanic with the usual minor slight idle dipping.
Bosch Hammer system adaptation.
I drove home without idle dipping.


My conclusion is that the DME reset with the battery disconnection technique is very different to the Bosch Hammer system adaptation.