I have a 94 coupe that is overheating. It slowly moves up in temp. It took about 30miles of stop and go driving to move up to 240 deg. I am running a hypertec program with 160 thermostat. Temp outside was about 80deg and I was not running air conditioner. I turned on the heater vent and temp seamed to drop a little. I ck the fans and they were truning. I think the raditor might be the problem but not sure. Have 104000 miles and water pump is 9months old. Suggestions please. If it is the raditor how hard and how long to pull. Thanks . tbmoore@cableone.net


[Modified by tbmoore, 5:39 AM 5/26/2003]

 

???

 

Sorry for the typo's.... have corrected..thanks

 

make sure you are not leaking antifreeze..if you are the leak needs to be fixed ..if not then you should take the radiator out and clean all the fins and flush cooling system and maybe even a new thermo because it might be sticking as long as the fans are coming on like you mentioned. Last summer I took out my radiator and the temp dropped 10 degrees while the car is on the highway so it will help out for sure.


[Modified by Trey96LT1, 6:16 AM 5/26/2003]


[Modified by Trey96LT1, 6:18 AM 5/26/2003]

 

Don't just check to see that the fans are running, but make sure they're actually pulling air... I chased a hot running problem for a couple of months on my older Camaro... Even though both fans were running, the primary fan was turning noticably slower than the aux fan...

Replaced the fan and felt much more air drawn across...

If you get hot like that and it will eventually cool off again when you can sustain a good speed 40-50+ mph, then I would suspect a weak fan motor... The fans only run below 40mph...

Also a check for debris between the radiator and A/C condensor would be good too... Look from the passenger side, there should be a small gap that you can see between there... You'd be surprised what you'll find there, especially if it hasn't been cleaned before or in a long time... :crazy:

 

If you arent going atleast 35mph the temp will climb to 240' even with a 160' t-stat . 1. check the area between the condenser and the radiator for debris and 2. have the computer reprogramed so the fans come on at 210' and shut off at 185'.

 

If you aren't running the A/C, the fans don't come on till 228 (stock, I don't know if you used the HT to turn on fans at a lower temp). Secondary fans comes on at 238.

What is your temp at a steady speed of 40mph? That's about the break even point between fans and natural airflow.

Pulling the radiator is not difficult. The hardest part are the 6 screws at the bottom of the shroud. I turned them from under the front with pliers on the threaded end until they were finger loose.

Be very careful with the fins on the radiator, they are about the strength of heavy duty aluminum foil.

Have you done anything to the car recently or has this been building over time?

 

Took the car to the raditor shop and they confirmed my guess. The raditor was about 2/3 plugged and there was grass ect between raditor and air condenser. Should be ready tomorrow. The charge will be $105. Seems like a fair price for everything. I am going to replace the Hoses while it is off at the cost of the hoses. Thanks for the help. terry

 

I'm not sure about the '94 but that's not how the '95 works. According to my service manual and my eyeballs the fans work together, on and off together. Low speed on at 226 off at 221, high speed on at 235 off at 230. Both fans.

:cheers:


[Modified by Atok, 7:05 PM 5/27/2003]

 

'94s only have single speed fans. It helps collect all the debris in one place to really clog up the radiator :rolleyes:

 

I’d like to chime in hear and get some opinions if I can. I’m having a similar problem with my 92. This happen last year about this time and it was cured with a 160 degree T-stat, Hyper Tech chip and a coolant flush. The car never broke 205 all summer long and I’m in Arizona! Now the problem is back. Fans kick on when they should, no debris between condenser and radiator, coolant changed last year at this time and the t-stat and chip are only a year old, radiator is two years old. It only over heats in stop-in-go with the A/C on, otherwise I can idle all day in 100+ heat with no problem. I had my tech look at it and he confirmed everything APPEARED to be working correctly, and he couldn’t get it to over heat after driving it for two days. My guess is he never turned on the A/C. Just to ease my mind, I drove around with the A/C on for a while then pulled it into my garage when the temps started to climb and just watched it. With the A/C on the temps climbed to 230 before I got nervous and turn the heat on. Temps then steadily started to fall. At about 210 I turned the A/C back on and temps rose to about 240 before I shut the car off. At that point coolant was boiling in the system and in the overflow tank and about ¼ cup spilled over. Any Ideas? :banghead:

 

Sounds like your fans aren't working properly.

When the A/C is on they fans are primarily controlled by the pressure in the condenser and secondarily engine coolant. Do you get ice cold air from the A/C vents? If not, maybe it's as simple as recharging the freon. If that does it, you might what to have some dye added as well to find out where the freon is escaping.

Also, you might not have visible debris between the condenser and the radiator, but the fins could be clogged preventing air flow. I'd pull the radiator and clean it, first. There's a TECH TIP for it.


[Modified by John Row, 3:24 PM 5/28/2003]

 

I wouldn't say it's ice cold :nonod: but, it has been above 100 every day for the last week or so. :confused: I've had the car for about 2 1/2 years now and I've never had the A/C system charged....maybe I'll try that this weekend.