86 iroc overheating. need help!!
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i have an 86 iroc(and a 02 SS)/ my iroc is overheating, its a rebuilt 305, and i've changed my radiator, my ac condensor, my water pump, my thermostat, my hoses, and i have no cats, and a new muffler. the heads are also rebuilt, but i havent checked them to see if they're cracked, or if they were cut to short, someone told me that could be a problem. someone also told me that if my intake gasket was put on backwards it would cause it to everheat, so does this sound logical or does ne one have ne idea what it could be????? thanx 4 ne advice................
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Originally Posted by ls1_doc
When does it overheat? (on the freeway, sitting at red lights, in town driving, etc..)
Also how quickly does it overheat?
Also how quickly does it overheat?
I blew up my radiator in my 89 back in 2000. The secondary fan relay was shot, so I replaced that and wired the 2nd fan to come on with the 1st. It kept things a lot cooler, especially in traffic.
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Never heard the story about backwards inake gaskets. Almost laughed.
My 85 IROC would always get hot idling, and cruising with a/c. I unpluged the A/C high pressure switch which made the fan (1) run all the time. It kept it cooler driving through town, but could not handle the A/C all the time. Besides the fans, if the air dam under the car is worn badly or gone it would hurt temps on the highway.
My 85 IROC would always get hot idling, and cruising with a/c. I unpluged the A/C high pressure switch which made the fan (1) run all the time. It kept it cooler driving through town, but could not handle the A/C all the time. Besides the fans, if the air dam under the car is worn badly or gone it would hurt temps on the highway.
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Originally Posted by Cstick
Besides the fans, if the air dam under the car is worn badly or gone it would hurt temps on the highway.
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it overheats when im driving in town, if im on the freeway it stays cool since its getting all the air pick up, as sson as i get off the freeway the temp will rise up in a matter of 3-5 min, and it will keep rising. say i was driving after the car had been sitting for a while, the emp would increase, and after about 20-25 min it would reach 220, my thermostat is a 220, and the temp would just cont. to rise. i had an ac system hooked up, but it doesnt work, but either way this would happend before that... ne ideas??? if yall need more info let me know.....thanks!
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no...see i have a new air dam under the car and it has dual fans that come on as soon as the car turns on, so its not that.... as u can see it really should not be overheating, but it is. so i dont know... anyone have any idea what it could be????
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a so-called "high performance" water pump was installed, the radiater cap, well it was changed like a year and a half ago, but it should still be good, both lower and upper hoses were replaced less than 6 months ago, which was a bitch, cause no one had the hoses that fit my car, air in system, hum???? well my air filters were replaced about two years ago, i have a good air dam, but my massive air flow comp. is from a 6 cylinder camaro, could that be the problem? i ran that thru my mechanic before i put it in, he said it was cool.... what else is would be part of the air in system?????
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When was the last time you changed the thermostat. If your car overheats multiple times like it has it can fail a thermostat. There is a wax pellet in the thermostat that you can start to boil out if it gets that hot, causing the thermostat to act slow.
Make sure you did not buy a "Fail Safe" thermostat. Once they over heat they stay open all the way.
Air in the system? Take the cap off when it is cold and warm the car up with it off, and the heater on to get and air pockets out.
Do you have a scan tool to check the temp the computer sees. I put a aftermarket guage in mine to read more "acurately". It read about 10 degrees warmer sitting at a stop than what the computer saw. Lean condition will cause a car to run hotter, check out the o2.
I am sure you have tried some of these ideas, but just want to make sure.
Make sure you did not buy a "Fail Safe" thermostat. Once they over heat they stay open all the way.
Air in the system? Take the cap off when it is cold and warm the car up with it off, and the heater on to get and air pockets out.
Do you have a scan tool to check the temp the computer sees. I put a aftermarket guage in mine to read more "acurately". It read about 10 degrees warmer sitting at a stop than what the computer saw. Lean condition will cause a car to run hotter, check out the o2.
I am sure you have tried some of these ideas, but just want to make sure.
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i dont have the scan system, and it is a fail safe thermostat, by cap, you mean the radiator cap? and i should turn the car on, with the heater on? and what am i looking for, or what is this gonna do for the car???? i will change the thermostat, what temp do you recommend?? well thanx stick, and eveyone else..
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by "cap" he does mean the radiator cap, and by doing what he has said it will get the air out of your cooling system which will help with the curculation. I think the stock thermostat is a 195* but i ran a 180* in my 87 iroc and it seemed to help. Also, just because you replaced the hoses doesn't mean that its not collapsed, i've seen it look fine at idle but once you get onto it some it collapsed. If all else fails, i bought a spal dual fan setup and used a manual fan switch for mine, cooled it down in a matter of seconds. An aftermarket gauge is also a GREAT idea, dont trust the stock one.
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I have a '87 IROC Lb9
and finally figured out that my overheating
was due to the fact that the #1 fan was not working at all!
As long as i was moving it was fine.
Pull up to a stoplight and about 10secs. later the temps would climb.
The #2 fan comes on at the appropriate temp.
A lot of good that does, when the car is already overheating.
It will usually start dumping coolant out of the lower radiator hose at around 220 degrees.
and finally figured out that my overheating
was due to the fact that the #1 fan was not working at all!
As long as i was moving it was fine.
Pull up to a stoplight and about 10secs. later the temps would climb.
The #2 fan comes on at the appropriate temp.
A lot of good that does, when the car is already overheating.
It will usually start dumping coolant out of the lower radiator hose at around 220 degrees.
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well im gonna have to check that lower hose, and change my thermostat, but not before i do that thing with the cap, but whether or not the gauge is marking accurately, i think it is, cause i could feel and smell the car overheat, and i do have dual fans that are on a direct connection, so as soon as i turn on the car, they go on as well, well if anyone has ne other input, it is appreciated!!
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well i already got the new car, but i need this one to work too, hey does anyone know how to get their car into "overhauled" i bet foose and his team could fix this problem, and all the other problems with the car!!!!!