c4 overheating
Thread Starter
5th Gear
Joined: Feb 2015
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c4 overheating
I have an 1987. The issue I am having with it is it likes to climb up to 240 degrees, possibly hotter, I always shut the car off before it gets to much hotter. In the past I had issues with the overheating. I had replaced the radiator fan and that's still working. I don't see any obstructions on it or anything like that. I looked under the front of the car, and there doesn't seem anything to be blocking the radiator when from air flow. While it's idling it climbs up to 240, that's before the oil temp even comes close to catching up. Leaving the oil around 165 before I shut off the car. I just recently replaced the upper radiator hose cause it was leaking, but the car is still overheating. I refilled the coolant level, and I've taken out the thermostat, to see if it was just the thermostat, to let it run continuously open.
So my question is could it be possibly a bad sensor? The water pump, or something else? Would the AC harness if it kicked on, cause it to get that high? Also it's kind of idiling around 11 where it used to idle lower than that before.
So my question is could it be possibly a bad sensor? The water pump, or something else? Would the AC harness if it kicked on, cause it to get that high? Also it's kind of idiling around 11 where it used to idle lower than that before.
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Joined: Mar 2015
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I have an 1987. The issue I am having with it is it likes to climb up to 240 degrees, possibly hotter, I always shut the car off before it gets to much hotter. In the past I had issues with the overheating. I had replaced the radiator fan and that's still working. I don't see any obstructions on it or anything like that. I looked under the front of the car, and there doesn't seem anything to be blocking the radiator when from air flow. While it's idling it climbs up to 240, that's before the oil temp even comes close to catching up. Leaving the oil around 165 before I shut off the car. I just recently replaced the upper radiator hose cause it was leaking, but the car is still overheating. I refilled the coolant level, and I've taken out the thermostat, to see if it was just the thermostat, to let it run continuously open.
So my question is could it be possibly a bad sensor? The water pump, or something else? Would the AC harness if it kicked on, cause it to get that high? Also it's kind of idiling around 11 where it used to idle lower than that before.
So my question is could it be possibly a bad sensor? The water pump, or something else? Would the AC harness if it kicked on, cause it to get that high? Also it's kind of idiling around 11 where it used to idle lower than that before.
and for the idle find your vacuume leak
Last edited by antfarmer2; Apr 19, 2015 at 04:35 PM.
Le Mans Master
Joined: Jul 2004
Posts: 6,228
Likes: 698
From: Clifton Park, NY ............Clearwater, FL ... 85 Original Owner
I have an 1987. The issue I am having with it is it likes to climb up to 240 degrees, possibly hotter, I always shut the car off before it gets to much hotter. In the past I had issues with the overheating. I had replaced the radiator fan and that's still working. I don't see any obstructions on it or anything like that. I looked under the front of the car, and there doesn't seem anything to be blocking the radiator when from air flow. While it's idling it climbs up to 240, that's before the oil temp even comes close to catching up. Leaving the oil around 165 before I shut off the car. I just recently replaced the upper radiator hose cause it was leaking, but the car is still overheating. I refilled the coolant level, and I've taken out the thermostat, to see if it was just the thermostat, to let it run continuously open.
So my question is could it be possibly a bad sensor? The water pump, or something else? Would the AC harness if it kicked on, cause it to get that high? Also it's kind of idiling around 11 where it used to idle lower than that before.
So my question is could it be possibly a bad sensor? The water pump, or something else? Would the AC harness if it kicked on, cause it to get that high? Also it's kind of idiling around 11 where it used to idle lower than that before.
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Joined: Apr 2002
Posts: 10,036
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From: Anaheim CA
Sounds like the coolant temperature sensor on the front of the intake manifold is bad (or the connector/wiring associated with it). You might have a corroded pin in the connector. If the ECM thinks the coolant is cold it won't turn on the cooling fan.
Does the cooling fan run when the engine gets hot? Do you have the auxiliary fan (in front of the A/C condenser)? If so, that should come on at 238°, which would be in the neighborhood of the temperatures you're reporting.
Does the cooling fan run when the engine gets hot? Do you have the auxiliary fan (in front of the A/C condenser)? If so, that should come on at 238°, which would be in the neighborhood of the temperatures you're reporting.
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From: Freedom is never more than one generation away from extinction.
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Do a search and read. There are ten pages of "overheating" posts to choose from.
Here's my point, there are YEARS of experience in this forum's history.
And the SEARCH feature is the only way to access this gold mine.
Simply starting a new thread only scrapes the current surface of knowledge.
And most of this knowledge is speculation from noobs.
Maybe not in this thread, since the problem here is very common in C4's.
Goto search and use the advanced feature for searching "topics" not the default.
Here's my point, there are YEARS of experience in this forum's history.
And the SEARCH feature is the only way to access this gold mine.
Simply starting a new thread only scrapes the current surface of knowledge.
And most of this knowledge is speculation from noobs.
Maybe not in this thread, since the problem here is very common in C4's.
Goto search and use the advanced feature for searching "topics" not the default.
Thread Starter
5th Gear
Joined: Feb 2015
Posts: 5
Likes: 0
Checked
Checked behind the fan shroud and what not. No trash. Nothing blocking the radiator and after I replaced the fan behind the radiator it runs whenever the car is on. It's done that since I have installed that. The car used to stay about 160's to 180's. About to try and burp it. See if that helps
Last edited by Jkerps01; Apr 22, 2015 at 03:24 PM.
Le Mans Master
Joined: Jul 2004
Posts: 6,228
Likes: 698
From: Clifton Park, NY ............Clearwater, FL ... 85 Original Owner
Checked behind the fan shroud and what not. No trash. Nothing blocking the radiator and after I replaced the fan behind the radiator it runs whenever the car is on. It's done that since I have installed that. The car used to stay about 160's to 180's. About to try and burp it. See if that helps