Thread: overheating issue

ok well my 04 grand prix with the 3.8l na seems to be overheating when going up large hills. i got this thing with a ton of problems. so far ive replace the head gasket with rebuilt heads, new radiator, new tranny, new thermostat, new water pump, flushed the cooling system. the radiator fans are working correctly. it not using any water and has no water leaks. the head gasket isn't leaking and it never overheats normal driving, just when you go up a 10 mile hill. im thinking maybe my cats clogged anyone have issues with the cataltic converter my car only has 120k. any input would be helpful. i guess you only pay 1000 buck for a reason. oh by the way i wasn't with the car when my woman was driving and she pulled over when it got to 3/4 of the way up the temp guage. i guess she also said it seems to have a loss of power no check engine light

i think i figured it out. all that you stated were all ready done and i bleed the cooling system with a vacuum based bleeder that doesn't leave behind any air pockets. well the other night i noticed some antifreeze was leaking out of the housing even though it was a brand new thermostat. so i decided to change it with a gm thermostat. well now its not overheating and the system is building pressure correctly. also instead of the coolant needle running right between the 2nd notch and 3rd notch, its now running right below or right above the 3rd notch. my woman miss took the area above the 3rd notch and the 4th mark as way overheating which it is running too hot but not blowing up overheating. the way they have the red marks is missleading. shes going to drive it 100 miles tomorrow so we will find out. hopefully i just got two crappy thermostats for kragen which wouldn't surprise me.

also i noticed im getting a lot of lifter racket when starting up and it last longer than it should . i know the guy i got it from never changed the oil, literally never, probably changed it once a year with crappy oil. i think im going to throw a new set of main and rod bearings.

If you pull the bearings ... at all. Have that done at a machine shop and align bored or you'll most likely kill your motor in say 2-200 miles. Our motors are very ....extremely finicky about bearings.

Originally Posted by BillBoost37

If you pull the bearings ... at all. Have that done at a machine shop and align bored or you'll most likely kill your motor in say 2-200 miles. Our motors are very ....extremely finicky about bearings.

Interesting. When I changed pistons and bearings I didn't have it bored or anything. Been running strong now for 100k miles. Just dumb luck?

From everything I've seen, tried and read about. I'd say yes. Maybe I'm wrong..there's far too many that have failures though.

Yeah..there's a couple goofy things about these motors. The bearing caps like to distort. Which then causes bearing issues. If you search around..you'll find an overwhelming amount of guys that say..if you don't machine shop it..don't touch the bearings.