I've been getting code 14 (Coolant Temperature Sensor triggers this apparently) in my 1987 Pontiac 6000 when checking the engine blink codes. I did replace the oxygen sensor (this cleared code 45 I was getting) and the Coolant Temperature Sensor, and then unhooked the battery for about 20 seconds and hooked it up again. Code 14 is still getting stored. Note that the SES light comes on after the radiator fan runs for a little while. The fan then won't go off again until the car is turned off. Then if you start the car too soon it all goes on again. But if the car has set awhile to cool down, it won't turn the fan and the SES light on for awhile. Before I replace something else I would like to get some ideas on the following possibilities... as in would any of the following conditions also trip up code 14?
- The temperature sensor has failed?
- The wires to the coolant temperature sensor might be busted or faulty?
- The radiator going bad? (it does have a couple fins missing but it's deterioration rate in the past 4 years has been minimal, there are no leaks, holds 50-50 real well.
The fan goes on if the coolant temp. sensor is hooked up then the light goes on after awhile. Disconnect it and the fan turns off after awhile. Plug it back in and the radiator fan goes on and so does the SES light again.
I also have an air conditioner which since leaked out all the freon a couple years ago, so I never use it anyway. I understand from reading somewhere that the radiator fan also is used for the air conditioner. Could something in the air conditioning system also be causing this? I don't see it likely but I don't know. :)
Any ideas that would trip up code 12 would be a help. According to BAT's problem code for my engine (2.5L TBI VIN-R) it means the coolant temperature sensor was detecting a temparature of about 275 deg. F for more than 3 seconds.
My temperature light is not lit so there is no indication that I know of that the car is actually overheating. No physical signs (ie. no steaming, etc.) Thermostat is new (replaced last fall) and new gasket sealed properly. I know the temp. light works because when you turn the key and all lights go on (a self-check I assume) it lights with everything else that's supposed to briefly. So if there was an actual overheat, then the temp. light would come on, I'd assume. And since it hasn't I assume that maybe either a sensor is going bad or something is giving false info to the ECC?
Ideas and things to try would be appreciated.
-- [*]~ Fuzzie Dice ~[*] Kitt: 1987 Pontiac 6000 w/ 145,000+ Miles Knight Dreams: The restoration of Kitt