Pulled the twin cam out of a 95 (silver cover) and replaced it with a 98(I believe) twin cam (black cover). The 95 had two coolant sensors on the left side of the head.....the 98 has one. Short of swapping heads or drilling the 98, can I do anything with the wiring to make the fan operate properly??

 

2 wire coolant sensor (95) was for the ECTS, and went to the PCM. Single wire temp sensor(95) was for the dash temp gauge.


I believe 95 was the last year the DOHC's had 2 temp sensors. Therefore, the 98 engine should still have the 2 wire sensor (the ECTS) going to the PCM (95). This is the sensor that tells the PCM when to switch the fan on and off based on coolant temp in the head.


The single wire sensor for the dash temp guage does not have to be connected for the fan to operate correctly. So it should work as is.


If your fan is not operating at all (won't kick in till about 3/4 tick on temp guage, which you now can't read cuz it is not connected), check the fan relay -- if that is ok then check the fan motor itself.


You may also wish to check out if there were any changes on the PCM/wiring (95 vs 98) to be sure everything else is what it seems.





Derf