: Starting Problem with 78 Seville 5.7L Engine

12-19-09, 12:47 AM
I have tracked this starting problem to one of two things. Now I need to find the parts, which of course have been discontinued. Does anyone know where I can get an air or coolant sensor GM Part Number 1609968? Also, I need to find the EFI switch connectors for two of my injectors. They are not making good contact with the injectors. Any help in locating replacements would really move this project forward.

12-19-09, 02:49 PM
What is the problem??? The coolant sensor (Front drivers side of engine) acts like a choke. After the engine warms up the computer ignores it's value.

12-19-09, 06:18 PM
"where I can get an air or coolant sensor GM Part Number 1609968?"

I've got one. (NOS) Never been used. It's been in my tool box for 30 years. I tested it in hot & cold water today. It works OK. Send me a PM. I'll help you with the diagnosis to be sure it's the sensor. The sensor is expensive.

12-19-09, 10:29 PM
The problem is that the Seville won't start. I understand that the coolant sensor can cause this when the engine is cold. I have checked out the ECU and replaced the fuel filter. The vacuum connection on the ECU was not tight, so I replaced the hose and put on new clamps. The air sensor tests 500 ohms and there is no reading on the coolant sensor. Two of the fuel injector switches aren't make consistent contact, so I want to replace them and check out the coolant sensor.