Stupid Question
Thread Starter
Instructor
Joined: Sep 2004
Posts: 122
Likes: 0
From: Salt Lake City UT
Stupid Question
Why do the TPIs idle so low? i also noticed that they run really really hot especially in traffic and its bugs the **** out of me ever since i've bought the car a few years back. Why? the F-Bodies dont run that hot and its almost the same motor.
Melting Slicks
Joined: Aug 2003
Posts: 3,409
Likes: 400
From: Lakeville MI
Two answers: Fuel economy and emissions.
Idle rpm is controlled by the ecm. The fans vary by year and option, but are primarily controlled via the ecm, but some years also have an aux fan which is controlled by a switch in the driver's side cylinder head.
The cooling fan or fans (depending upon year and options) are not active until 220 degres or hotter for the main fan and 235 or so for the aux. fan.
Reducing the temperature range of the cooling fans is a popular mod for these cars, along with lower temp thermostats either 160 or 180 degrees.
This ususally accomplished with a chip or chip tuning. Sometimes with manual or temperature sensitive switches with a 200 on/180 off setting.
For example, on my 88, I use a 160 degree t-stat and have both fans wired and programmed for 82.25 C (180 f) on and 71 C (160 f) off, for both ac on or ac off
Previously, I used a 200 on/180 off switch sold by ecklers, mid america, etc., that was wired to control both fans, either via ecm or via switch
Idle rpm is controlled by the ecm. The fans vary by year and option, but are primarily controlled via the ecm, but some years also have an aux fan which is controlled by a switch in the driver's side cylinder head.
The cooling fan or fans (depending upon year and options) are not active until 220 degres or hotter for the main fan and 235 or so for the aux. fan.
Reducing the temperature range of the cooling fans is a popular mod for these cars, along with lower temp thermostats either 160 or 180 degrees.
This ususally accomplished with a chip or chip tuning. Sometimes with manual or temperature sensitive switches with a 200 on/180 off setting.
For example, on my 88, I use a 160 degree t-stat and have both fans wired and programmed for 82.25 C (180 f) on and 71 C (160 f) off, for both ac on or ac off
Previously, I used a 200 on/180 off switch sold by ecklers, mid america, etc., that was wired to control both fans, either via ecm or via switch
