# 1998 Malibu overheating



## stressedout (Jul 17, 2005)

*98 malibu overheating*

hey I'm new to this site. I have a 98 malibu, engine sounds good, and everything runs fine, but the temp gauge fluxuates. We have replaced the hoses, thermastat, water pump, radiator, cap for the resavoir, and still overheating problems. We even took off the intake and replaced those gaskets. Is there anything I can do, or should I trade this car and not look back..... :4-dontkno if you have any ideas please e-mail me. My wife is all over my *** about trading it in. my e-mail is plattman78{at}hotmail.com


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## maddbob (Feb 13, 2005)

Try replacing head gaskets in both circumstances,since '75 all overheating problems in my cars and trucks have been due to warped heads,in '75 all manufactuers changed the specs. on their castings to meet the cafe standards at the time,so as to reduce engine weight by 30%.This didn't leave much meat on cylinder head deck,so most manufactures went to steel shims by '92,to reduce head warpage the opperative word here is "reduce",so occasionally,this occurs.Combine weaker castings,increased cylinder pressure and bad gas,it's a wonder this does not occur more often,but chalk that up to superior computer control of cylinder pressure.So I say cut to the chase and go for the head gasket,don't forget to re-flatten the head on a milling machine at your local engine machine shop.Maddbob


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## Midnight Tech (Dec 31, 2001)

This may sound dumb stressedout, but does it have the correct antifreeze in it? Use of the wrong stuff can cause it to overheat, as well as not running a 50/50 mix.


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## JamesO (Mar 30, 2005)

You say the temperature gauge fluctuates, but does the car actually overheat?

Overheating meaning the radiator boils over into the overflow tank?

I assume this car has electric cooling fan(s)? Do they appear to run?

Has someone been able to connect a scan tool to read the engine temperature via the unde dash connector and compare it to what the temperature gauge indicates? Usually some of the auto parts stores like Auto Zone will do this for free?

If the car is not actually boiling over, you may have a problem with the temp guage, electrical system, a bad ground or a bad temperture sending unit?

JamesO


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## shadetreemech (Mar 31, 2006)

*98 Malibu Overheating*

Had the same problem with a 98. The head gaskets were actually gaskets, but the intake manifold facotry gasket was the liquid gasket. The pressure actually pushed its way through the liquid gasket on the right side of the engine just above the transmission. We had that replaced and the overheating problems have stopped. By the way, the problem started with antifreeze leaking ever time the car got hot.


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## crazijoe (Oct 19, 2004)

Fluxuating temps is an indication of air pockets in the coolong system. Usually in the head(s). Most engines will have air bleed-off valve(s) located in various places (intake manifold, thermostat housing, etc.).


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## Mullet Man (Oct 9, 2005)

Sound like crazijoe hit it on the head! You MUST get all the air out of the system on a GM. Also make sure you are using "DexCool" antifreeze!


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