Need help with Fans turning on.
Thread Starter
Racer
Joined: May 2012
Posts: 392
Likes: 19
Need help with Fans turning on.
When does the passenger fan supposed to turn on? I had the temp up to 228 degrees. the drivers side fan came on, turned on the A/C and the passenger side did not come on? Any ideas as what to check? It's a 93 LT1 Solved, use paper clip between a and b on adl. both fans come on.
Last edited by charliet615; Dec 28, 2018 at 01:26 PM.
Melting Slicks
Joined: Jul 2005
Posts: 2,649
Likes: 863
On the LT1/LT4 motors - the fans are controlled by the PCM. First fan comes on around 220 - the second one around 228 - 230. First fan also runs when A/C is requested. When driving around in low speeds - temps in the 220 - 230 range are nothing unusual. Much over 230 is abnormal, and on a straight highway cruise - anything over about 200 is abnormal
These motors run hot from the factory - I believe that the feeling at the time was that it helps emissions. If you want the fans to come on earlier - you can either reprogram the PCM (not very easy on a 1992 - 1994 with the OBDI) / wire in a switch to manually turn them on / wire in a separate temp switch to turn them on.
These motors run hot from the factory - I believe that the feeling at the time was that it helps emissions. If you want the fans to come on earlier - you can either reprogram the PCM (not very easy on a 1992 - 1994 with the OBDI) / wire in a switch to manually turn them on / wire in a separate temp switch to turn them on.
