Heating issue - NO HEAT!!!!
10-27-2008, 06:42 PM
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Heating issue - NO HEAT!!!! I picked up a 96 Cavalier for a winter beater. Only problem is that the heat doesn't work at all. Obviously, winter weather is upon us, and I froze driving it. The temp gauge barely registers any heat in the cooling system. The car doesn't overheat either. What's the problem here?
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11-11-2008, 11:01 PM
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Ok, let me edit that. It gets hot when idling, and driving less than 50mph. The heat decreases with speed. The cooling fan is staying on all the time. I doubt it's the relay though.
11-11-2008, 11:08 PM
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Ok scratch that. lol So you have a new stat and you get heat, just not when you are moving above 50mph.
How cold is it up there?
If your fans are staying on that is a problem. Most cars fans dont kick on until the coolant gets above 200*F. Relays work off electromagnetism so you might have a short in the signal wire to the relay causing it to stay closed.
Pull the relay and see if it helps. Dont take her on a long haul just enough to see if it works. If you get heat your problem lies in the fans. That could mean a bad relay or a computer error.
How cold is it up there?
If your fans are staying on that is a problem. Most cars fans dont kick on until the coolant gets above 200*F. Relays work off electromagnetism so you might have a short in the signal wire to the relay causing it to stay closed.
Pull the relay and see if it helps. Dont take her on a long haul just enough to see if it works. If you get heat your problem lies in the fans. That could mean a bad relay or a computer error.
11-14-2008, 09:08 PM
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Do the air modes work (panel, floor, defrost, etc?) Also are you only trying to get heat with the defroster on? Cause the fans may be coming on since the A/C compressor is on during defrost
11-22-2008, 09:16 PM
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The compressor & fans will run if the defrost is selected.
Dont know if you can trust the coolant temp gauge though, they are known to be inaccurate at times.
Heat decreasing w/ speed would suggest a heater core is plugged. You might need to flush it out or even replace it.
Another possibility is the blend door inside the dash. If it is not going to the full hot & sealing, you can get poor heat. It will worsen w/speed due to the air being induced thru the fresh air intake in the cowl.
The thermostat should be able to maintain enough temp to give you heat. They have been know to be problematic as well I think delco has a new one/updated version for the 2.2. Is this a 2.2 or a 2.4?
If the fans are on all the time that issue needs to be addressed as well .
If they are on HVAC controls off, pull the fan relays. If they go off then you know where to start looking. Lots of those early OBD-II J bodies had problems w/ PCM's too.
They put it on top the air dam under the passenger headlamp. Lots of water intrusion problems.
Dont know if you can trust the coolant temp gauge though, they are known to be inaccurate at times.
Heat decreasing w/ speed would suggest a heater core is plugged. You might need to flush it out or even replace it.
Another possibility is the blend door inside the dash. If it is not going to the full hot & sealing, you can get poor heat. It will worsen w/speed due to the air being induced thru the fresh air intake in the cowl.
The thermostat should be able to maintain enough temp to give you heat. They have been know to be problematic as well I think delco has a new one/updated version for the 2.2. Is this a 2.2 or a 2.4?
If the fans are on all the time that issue needs to be addressed as well .
If they are on HVAC controls off, pull the fan relays. If they go off then you know where to start looking. Lots of those early OBD-II J bodies had problems w/ PCM's too.
They put it on top the air dam under the passenger headlamp. Lots of water intrusion problems.
11-25-2008, 05:42 AM
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The compressor & fans will run if the defrost is selected.
Dont know if you can trust the coolant temp gauge though, they are known to be inaccurate at times.
Heat decreasing w/ speed would suggest a heater core is plugged. You might need to flush it out or even replace it.
Another possibility is the blend door inside the dash. If it is not going to the full hot & sealing, you can get poor heat. It will worsen w/speed due to the air being induced thru the fresh air intake in the cowl.
The thermostat should be able to maintain enough temp to give you heat. They have been know to be problematic as well I think delco has a new one/updated version for the 2.2. Is this a 2.2 or a 2.4?
If the fans are on all the time that issue needs to be addressed as well .
If they are on HVAC controls off, pull the fan relays. If they go off then you know where to start looking. Lots of those early OBD-II J bodies had problems w/ PCM's too.
They put it on top the air dam under the passenger headlamp. Lots of water intrusion problems.
Dont know if you can trust the coolant temp gauge though, they are known to be inaccurate at times.
Heat decreasing w/ speed would suggest a heater core is plugged. You might need to flush it out or even replace it.
Another possibility is the blend door inside the dash. If it is not going to the full hot & sealing, you can get poor heat. It will worsen w/speed due to the air being induced thru the fresh air intake in the cowl.
The thermostat should be able to maintain enough temp to give you heat. They have been know to be problematic as well I think delco has a new one/updated version for the 2.2. Is this a 2.2 or a 2.4?
If the fans are on all the time that issue needs to be addressed as well .
If they are on HVAC controls off, pull the fan relays. If they go off then you know where to start looking. Lots of those early OBD-II J bodies had problems w/ PCM's too.
They put it on top the air dam under the passenger headlamp. Lots of water intrusion problems.
I'm not selecting defrost. Only dash vents.
The coolant temp gauge is pretty accurate, because it's sinking below operating range, and then I'm getting cold air.
I don't think it's the heater core, I was driving it tonight through heavy Chicago traffic, and it was pumping out PLENTY of heat.
Blend door is sealing, because it's not going cold quickly. It takes it a minute to cool off and it corresponds to the temp gauge.
I may pick up a Delco stat. It is a 2.2, and the thermostat is really poorly designed IMHO. However, this would make a 4th thermostat in a month.
Ok, I pulled the relay, and the fan turned off. Went to autozone, picked up a new relay. Fans are still on all the time! I'm starting to think that it's a PCM issue, which will really **** me off. What codes should it be throwing for a dead PCM?
11-25-2008, 08:09 AM
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Might not throw any codes at all. You need to scan that thing & see if there is a cooling fan request. It's either that or you have awiring issue. The PCM grounds the relay to turn it on thus activating the controlled circuit.
Try to drive it w/out the relay/no fans & see how the heat reacts.
Try to drive it w/out the relay/no fans & see how the heat reacts.
01-02-2009, 12:05 PM
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Any with the capabilityto get the GM data stream. there are many out there.
I caanot remeber if that is also a generic OBD-II info PID might be able to get it w/those scanners capable of generic info as well.
I caanot remeber if that is also a generic OBD-II info PID might be able to get it w/those scanners capable of generic info as well.
