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'03 3.1L overheating constantly

CnmnGrl

New member
Hi y'all. In February my car was overheating. Mechanic flushed system a few times and replaced thermostat. Apparently my car had been in a flood and I did not know it until then. I brought it home and it started overheating again. He came and flushed it again. He really flushed it a lot. It had a lot of cruddy goop in the system. Finally said I needed a new radiator. Radiator replaced, should solve problem. Worked for a while couple months, kind of. It still got hot, and I still had to glance at the gauge every 10 seconds.

Last week new mechanic said needs a new water pump. So replaced the water pump. I'm driving yesterday and all of a sudden it just starts getting hot. Like above 210. By the time I got home I had pulled over once for about 5 minutes to let it cool down, finally got home and it was boiling. in the red. It does fine for short distances. Called mechanic. He said I need a new radiator... Again.

Oh I forgot to mention, I had it looked at a couple of times between February and this last week, and both times was told the radiator was not new. And after mechanic took off thermostat, it was obvious the thermostat was not new, as it was full of rust and corroded and full of blue stuff. So now I need a new radiator. Mechanic said oh by the way after I replaced the water pump, the water wasn't getting to the radiator or vice versa . Am I chasing good money after bad? Do I need to bleed the air out of the radiator? Do I need to replace the Overflow container and the tube? I read in another similar thread that he replaced that and it solved his problem. It's very gross inside. If there was that much gook in the system, wouldn't it still be left over in the tank and continue to disperse into the system?

Also thermostat is off now since blue devil. Shouldn't it go back on? I won't have any heat or defrosters.
 
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Sounds like a possible bad head gasket. If the blue stuff is kinda crystalized, that's head gasket stop leak. I'm currently having a very similar issue on my 3.1l. Sounds like your mechanic doesn't know what he's doing.
 
I think the new dude got it right. After a 2nd radiator she's not hot. I repeat...SHE'S NOT OVERHEATING. I do need the head gasket replaced though sooo I'm looking for a new car.

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Yeah the 3.1s are ****. I'll never own another 3.1 as soon as I get rid of my current one. Now the 3.8 is a good engine. My 3.8 never gave me any major issues.
 
I had an 02 gpgt 3.8 I loved it. I'm looking for a new ride now but drove her around for almost 4 hours today and she stayed under 210

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If I can get mine to stay under 210, or even 225, it's a good day lol. I had a 99 gt that was the ****. Loved that car. I'd still have it if I wouldn't have been dumb and traded it for a lifted suburban that ended up being almost just as bad as the grand prix I have now.
 


Can't say that 3100's are bad motors. I have one with 247k in my driveway that won't die.

When you say your car was flooded, was that because there was a bunch of junk in the radiator? Like mud? If so it's likely the previous owner mixed dexcool with green coolant. Seen that many times and it makes a mess. Your radiators likely keep getting clogged with the junk coming out of the engine, heater core, etc. There is a way to get it cleaned out. Has your mechanic done a test to verify that the head gasket is indeed bad?
 
01 GP SE 3.1 with 210,000 miles and still going great. Have never had an engine issue since brand new (April 2001). Does not use an OZ of oil between 5,000 mile oil changes. Had a 98 GT 3.8 that needed a LIM gasket at 65,000 miles................
 
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