Started to get hot sitting in traffic

[Ourobos]

The wife has been driving the 03.. I have never had any overheating issues.. It was about 90 degrees here today. She was sitting in traffic for 10 minutes with the A/C on. Temp hand got up above 3/4 way, is ALWAYS at 1/2 max.. She pulled over and let it cool off, drove home with the heater on to dissipate some more heat.. I checked it out, coolant is full.. Fan is working.. Drove it tonight and it was just at the 1/2 way mark.. Any thoughts on why it would do this? 90 degrees is nothing, 100+ is coming, don't want any unexpected surprises then. Thanks

[fastblackmerc]

Might want to try burping the system.

[Zack]

Take the radiator cover off, and the secondary cover between the radiator and condenser.
Look down there, you will probably be amazed at the crap blocking airflow.
Wash out with a hose, then re-test.
It's always best to monitor engine temps electronically. The temp needle will stay at 20mph from 180-218
Any higher and it creeps up

[Ourobos]

Yeah mine is normally dead at 20 mph, now it creeps up about 1/2 more the way to the top, so it's 3/4 instead of 1/2. Did it to me today.. I verified fan is working. I'll go R&R the trash right now, if that doesn't do it I'll try to burp it, will update. Thanks guys.

[Ourobos]

Not any debris so to say down in there, there was some bugs / dust / dirt lightly saturating the radiator fins and condensor fins. I sprayed all that out. I could find no air in the system either, pure liquid. I'll take it out tomorrow or this evening when it's hot and see if spraying it out helped.

[MOTOWN]

Probably time for a 180* or 170* thermostat, and a flush.

[RubberCtyRauder]

did you follow the burping procedure?
http://reischeperformance.com/refill.html

[Ourobos]

^ Yes I did.. Other than double checking it tomorrow.. What is the stock range on these cars, 192?

[Badass_forever]

the rad could use a flush im sure, they get gummed up over time. To be honest, every car is different, your t-stat could of just been sticking and it might never happen again.

I have an 03 impala, it has a new rad, new water pump, new belt, new t stat, 99% of the time it is dead nuts in the middle and runs perfect, random without warning it will creep up too 3/4 and then not do it again, I have never understood why. it just... does.

[justbob]

You checked between the radiator and the condenser right? I have a 1/2" thick blanket of cotton every couple of years on the front side of the radiator. Looks clean as could be from the grill and the engine sides.


Builder Of Badassery

[8UWITH6]

Take the radiator cover off, and the secondary cover between the radiator and condenser.
Look down there, you will probably be amazed at the crap blocking airflow.
Wash out with a hose, then re-test.
It's always best to monitor engine temps electronically. The temp needle will stay at 20mph from 180-218
Any higher and it creeps up

What this guy said. Personally have a customer at work with a high mileage Marauder thought he had a major issue. Some degreaser, a hose and some labor time he was back running normal temps. You would not believe the crap on the front of his radiator. Good luck.

[Ourobos]

Yes, I removed both covers.. One leaf was all that was in there... The fins may have been a little clogged which I cleaned. Not sure if it'll be as hot around here this weekend, but if that didn't do it, I'm going to pull the thermostat and inspect it, then R&R the radiator.. I plan on driving this to Mustang Week at Myrtle Beach next month, so I definitely plan on solving it. Thanks guys

[Zack]

Don't remove the radiator, it is never a problem unless it's full of crap on the outside.
Buy a 180 stat from Napa or the Reische.
Burp, done.
I just repaired a MM with the same symptoms as yours. Bad tstat, even though it looked perfectly fine

[RF Overlord]

What is the stock range on these cars, 192?The factory thermostat is 188°.

[lifespeed]

Thermostats do go bad, and erratic behavior is pretty typical. They should be considered a maintenance item if yours has never been replaced.

I can't believe your wife noticed the temperature!

[Ourobos]

^ You and me both.. I'm surprised it wasn't "Yeah, you're leaking some fluids all over the pavement and I need a ride"..

She knows to be extra careful when driving my baby :D

[juno]

Yeah, check the thermostat. Also if you buy a replacement do the pan of water test to check the opening temp. You would be amazed how much they vary.