1985-1998 [Subscribe to Daily Digest] |
Guys,
Re-posting from a previous thread.
I been having a high idle issue once the engine temp reaches normal operating temp. The idle goes up to ~1100rpm. It was suggested that it could be the engine temp sensor which made a lot of sense. This is a new to me '97 Aero that I have been fixing up to become my daily driver, it is not yet on the road. but will be soon.
I finally got to replace the Temperature sensor that connects to the Trionic ECM. The problem remains, the high idle at normal engine temperature still there, no change.
The interesting thing is that with the engine idling, if I unplug the temperature sensor (Back of the head between injectors 2 & 3)there is no change at all in the engine idling, no check engine light nothing. Almost like it is not connected or bypassed. I check the connectivity between the temp sensor and the connector at the ECM and it is fine.
I am baffled..It is beginning to sound like the problem is in the ECM itself.
Any ideas on what I could try? Has anyone ever disconnected the temp sensor while the engine is running? I would expect to see some change in the engine idle and perhaps a check engine light.
Can the ECM be programmed to bypass the temp sensor maybe for testing purposes? Maybe the mechanic from the previous owner bypassed it in the ECM while troubleshooting the problem or for some other reason. Is it possible that the previous owner maybe had the ECU "chipped"? I read for example that a Stage 3 upgrade they may disable the knock sensor, maybe they do the same with the temp sensor? Anyone know? Is there a way to reset the ECM to factory settings?
Any ideas on what I could try would be appreciated.
TIA
Tony
posted by 134.242....
No Site Registration is Required to Post - Site Membership is optional (Member Features List), but helps to keep the site online
for all Saabers. If the site helps you, please consider helping the site by becoming a member.