GM 3.1L V6 coolant temp problem

check this out (gauge anomaly):

Are you suggesting that he has a LT1/LT4 engine in his Grand Am?

What if he didn't have Kool-It in his radiator before the heater core leak?

Verify that the replacement radiator has the same cooling capacity as the original. Some shops install cheaper radiators with fewer cooling tubes. They will suffice under normal operation, but you will notice elevated temperatures under extreme conditions.

First off verify with Pontiac what the normal operating temperature should be.

Next, have someone check the coolant mixture itself. If they used 100% coolant when it should have been mixed with 50% with water it will not transfer heat as effectively.

The shop only installs OEM parts, and I trust them in that respect.

If the radiator wasn't up to snuff, wouldn't I be getting close to normal temperature on the highway, but overtemp when doing stoplight- to-stoplight driving?

Yep, that's definitely a good idea. :-)

That's a pretty basic thing to screw up, but I suppose it couldn't hurt to check it out...

IMHO, hot on the highway but cool around town = airflow problem. There's nothing jammed in between the rad and the A/C condensor? I've heard of stuff like plastic bags getting jammed in there.

I would also confirm that they replaced the rad with the right size - maybe they inadvertently used one for a 4cyl, no AC Grand Am? Double check the part numbers.

Also, if the thermostat has been changed it could be to blame - the one in my truck stays closed until it's almost too hot (the needle starts to go past "normal" and then opens like crazy - the temp drops about 20 degrees and then it slams back shut and cycles like this for a while.) Nothing wrong with it, I just don't like it.

Lastly... check the connectors for the temperature gauge. A little dirt, a broken wire... could make your gauge read high.

you're not overheating, but 220 sounds high. On the cars I've owned, "normal" (aka the middle of the factory gauge) is around 190-210F.

Ray

Not necessarily, but there's nothing with thinking outside the box.

What was your suggestion to the OP?

Again, another option. Also, what is your suggestion to the OP?

Either participate positively, or dont participate.

Its a lot more likely to happen now that we have shelves full of the idiotic "pre-diluted" antifreeze and people get used to just dumping it in straight all the time.

You might be surprised at how may times that gets screwed up. People dilute pre-diluted coolant and don't dilute 100% coolant.