new 348 owner tech help

Try resetting your ECU. To do this, disconnect the battery, your's has a plug devise on the positive cable, just unplug it. Leave it alone for 15-20 minutes. Reconnect the power and start the car. Don't touch the gas or anything else. Let the car idle for 15 minutes. Your ECU will be reset and maybe this will cure your problem. It has mine more than once. Good luck.

 

Alan- Your car has the Motronic 2.7, which has a self diagnostic feature. Pages C78-C81 in the workshop manual will show you step by step how to download the MIL's to determine your problem. Once you find the problem, simply search the archives by key words for a fix.

 

Sounds like you have a bad thermocouple ecu. the insulating material cracks on the seams and allows moisture to infiltrate the electronics causing the failure.

on the 348, they are located behind the rear shock towers with one on each side for each bank. What happens is that the tc ecu sends a false exhaust over temp signal to the motronic ecu which in turn shuts down the bank to lower the temp.

unfortunatly a very common, expensive fail point of the 348.

Determine which bank you are losing and then swap the ecu`s left to right. If the bank lost follows, you have your problem.

best regards, jim

 

FWIW - I had some intermittant "slow-down" light messages until I replaced the CATS with test pipes - no more problems....

 

I would also suggest to go to the old site and do a search on :
348 AND "slow down"

there is almost TOO much information available. its a gold mine.