86 GT keeps overheating (Page 1/1)
owenspike AUG 23, 09:48 PM
My 86 GT keeps overheating. When I bought it, it didn't have a thermostat in it and kept overheating. I put one in and it still is. Should I remove the thermostat? Was it taken out for a reason? And why would it still be overheating? Thank you!
Patrick AUG 23, 10:15 PM
What indications are that it's overheating?

[This message has been edited by Patrick (edited 08-23-2020).]

owenspike AUG 24, 09:41 AM

quote
Originally posted by Patrick:

What indications are that it's overheating?




I've had it purge the coolant, and I get a check engine light that disappears after a few minutes of my car being off. However, my temp gauge says I'm well within operating temperature.
fierofool AUG 24, 09:58 AM
The check engine light is probably your EGR system. Remove the trim around the 'cigarette lighter' accessory port and peer inside. There is a black terminal attached to the underside of the console armrest. Insert a paper clip into the lower two terminals on the passenger side, turn the ignition to ON and watch the check engine light. It will flash 1 time then 2 times. This is a code 12, telling you the system is working. It will flash 12 for 3 times. Then it will go into any set trouble codes, flashing each code 3 times. Record those numbers. When the computer finishes flashing all set codes, it will again begin to flash 12 and start over.

Code 32 is the EGR system. If you don't have a Clymers or Chilton's manual, you can go to the home page of the forum and under ARTICLES you will find a listing of the codes.

In the meantime, don't trust your temp gauge to be accurate. I suggest that you reinstall the thermostat, take it for a very short drive to warm the engine, then let it sit in your driveway and idle. Open the front hood and wait for the cooling fan to come on. That should be at about 135*. Check your gauge to see if it compares.

Edited to correct the temperature. The fan should kick on at about 235*, not 135*.

[This message has been edited by fierofool (edited 08-24-2020).]

owenspike AUG 24, 10:49 AM

quote
Originally posted by fierofool:

The check engine light is probably your EGR system. Remove the trim around the 'cigarette lighter' accessory port and peer inside. There is a black terminal attached to the underside of the console armrest. Insert a paper clip into the lower two terminals on the passenger side, turn the ignition to ON and watch the check engine light. It will flash 1 time then 2 times. This is a code 12, telling you the system is working. It will flash 12 for 3 times. Then it will go into any set trouble codes, flashing each code 3 times. Record those numbers. When the computer finishes flashing all set codes, it will again begin to flash 12 and start over.

Code 32 is the EGR system. If you don't have a Clymers or Chilton's manual, you can go to the home page of the forum and under ARTICLES you will find a listing of the codes.

In the meantime, don't trust your temp gauge to be accurate. I suggest that you reinstall the thermostat, take it for a very short drive to warm the engine, then let it sit in your driveway and idle. Open the front hood and wait for the cooling fan to come on. That should be at about 135*. Check your gauge to see if it compares.



Thank you for the quick response! I'll check it after I'm done at school. I know I have a vacuum line that's missing a 3 inch long section of it, so it makes sense that its my EGR Vacuum lines.
Patrick AUG 24, 03:25 PM

quote
Originally posted by owenspike:

I know I have a vacuum line that's missing a 3 inch long section of it...



You definitely don't want a vacuum leak. Get that remedied.


quote
Originally posted by owenspike:

I've had it purge the coolant...



Read over my post Here regarding filling and "burping" of the system.

[This message has been edited by Patrick (edited 08-24-2020).]

owenspike AUG 24, 03:41 PM

quote
Originally posted by fierofool:

The check engine light is probably your EGR system. Remove the trim around the 'cigarette lighter' accessory port and peer inside. There is a black terminal attached to the underside of the console armrest. Insert a paper clip into the lower two terminals on the passenger side, turn the ignition to ON and watch the check engine light. It will flash 1 time then 2 times. This is a code 12, telling you the system is working. It will flash 12 for 3 times. Then it will go into any set trouble codes, flashing each code 3 times. Record those numbers. When the computer finishes flashing all set codes, it will again begin to flash 12 and start over.

Code 32 is the EGR system. If you don't have a Clymers or Chilton's manual, you can go to the home page of the forum and under ARTICLES you will find a listing of the codes.

In the meantime, don't trust your temp gauge to be accurate. I suggest that you reinstall the thermostat, take it for a very short drive to warm the engine, then let it sit in your driveway and idle. Open the front hood and wait for the cooling fan to come on. That should be at about 135*. Check your gauge to see if it compares.

Edited to correct the temperature. The fan should kick on at about 235*, not 135*.




That was the code I got! Thank you!!!
fierofool AUG 24, 10:32 PM
The 32 is a soft code, meaning the warning light goes away with ignition off and doesn't come back until certain speeds and conditions are met while driving. Sometimes it will go off and on while driving. It really won't hurt anything by driving.

First, with the engine cold and not running, disconnect the vacuum line from the EGR valve. Feel underneath the valve to see if you can touch the diaphragm. If you can, push up on it and cap the vacuum nipple with a finger. Release the pressure on the diaphragm and see if it comes back down while keeping your finger on the vacuum nipple. Or, if you have a Mighty Vac, pull a few inches of vacuum and see if it holds. If all is good there, it will be the EGR solenoid on the passenger end of the engine, just above the water pump.

I'll leave the overheating responses to Patrick, since he was first to address that issue.