I had a problem 6 months ago where the car would shut off after running for 3 minutes when i started it after sitting all day. I was able to restart soon after and never had any issues after that. It did it 4-5 times in a three week period and has been fine for a 1/2 year. Today i had the hood open to see if i could hear my exhaust leak from the engine compartment. It ran for 2 minutes, i then noticed the fan come on and run for a minute. That weird since the car was sitting for 24 hours and its 40 degrees outside and the car was just started. The fan ran about a minute. I heard a click from under the hood and the fan turned off. One to two seconds later the car died like the key was turned off. I waited a few seconds and turned the key and it started on the second try which isn't unusual. It runs just like normal so whats going on? I have Freescan if there is something i should be looking for. I was thinking the computer believes the car is running hot even though its still just warming up. I didn't pay much attention so the fan could have been off and on. I kept hearing the clicking noise. The SC and motor and headers makes it hard to hear well. Thanks in advance!

 

Alright i read a bunch of posts and saw that the fans stay on with an ses light. I have none or any codes. What do the fans use to determine when to come on. I assume its a sensor somewhere. The clicking sounds like my ac compressor on my Jimmy when it got low on freon and needed charged. The thing would constantly click and sounds a lot like my click now.

 

The fans turn on and off based on the PCM programming. The PCM uses the coolant temp sensor in the water pump housing. They also turn on when the A/C operates.

 

Hey so if your coolant sensor is messed up your fans wont come on????

 

Or they might stay on all the time. Stock programming is on at 226*F for the first fan (or low speed mid-94 and up) and 235*F for the second fan (or high speed). A faulty coolant temp sensor will also mess up the cold start fuel enrichment, idle speed and may prevent the PCM from going into closed loop. Freescan will show you what temp the sensor is reporting.

 

On my last datalog it was at 88.3 to 89 celsius. I had the car out for a while and it never went out of this range once it warmed up. I have the 160 degree stat. Could be going out just some times? It never looked off when i was checking it with the lap top. What would cause the car to die after the fans shut off? It was definately at the same time the fan shut off. I could hear it shutting down and when it stopped completely the car died immediately.