So I have a new replacement radiator, new Jegs dual fans that are constantly on, 160 Thermostat, water wetter added(Ive tried both with water and 50/50). Yes I have an air dam as well. My car while driving will climb slightly and stay around 220 and will even go a bit higher after 30 minutes of driving. The weird thing is it will slowly cool down when its not moving. Ive messed with the timing and still no luck. It's hot here in Texas I know but I had pretty much the same setup with my other 3rd Gen in Arizona and it stayed at 180. I'm totally stumped. The only difference was the other 3rd Gen didn't have the TA ground fx. Do you think there could be a lack of airflow from the front? Should I swap to the regular Firebird rear and front bumper covers and lose the TA look?

 

What shape is the airdam in?

 

what gauge? stock? i've never had a stock gauge read anything other than 220-230 degrees under normal conditions.

 

The airdam is in good shape. Nothing wrong with it at all

 

I'd blame the guage if it's stock - it's rare anymore that a stock guage is accurate as old as they are.

 

Im definitely not gonna put my trust in the gauge being wrong.

 

They make a radiator cap that has a thermostat built into it at Advanced Auto. Might try that to make sure your gage is on the money. Heres the link = http://shop.advanceautoparts.com/web...AMS_1459711279___

 

i think that the only thing else to try is the gauge.

 

Here's a couple odd Qs for 89FRMLA350---

Are the fans pushing instead of pulling??
Are they the kind that have low, med, hi speed settings & they are not going into med or hi??

IDK how to tell if they are multi-speed. A friend wired his fan, & when it came on, it was pushing instead of pulling, so a simple wire switch around fixed it.

 

What are your fuel trims like? Is the engine running lean? Lean AFR will cause high combustion temps and thus high coolant temp. Youll generally see a tendency for "pinging" in a this case but not always. As others have said, be sure to check your actual coolant temp. Never trust the in dash gauge without testing it against CTS data and a thermometer.

 

Are your engine and/or heads original to the car, or have you ended up somehow putting in a temp sender from another year than your gauge. Possibly calibrated differently?

 

Check the bottom radiator hose to see if it has the anti-colaspsing spring in it. If it don't then that's the problem. As you are driving the water pump may be sucking that hose shut. It won't happen while at idle or very low rpms cause the pump will be turning slower. If the spring isn't in the hose you can test it buy watching the hose while a buddy rev the engine, it should colaps. Just had a custermers TA do that very same thing, overheating while driving but fine at idle.

 

Obvious, but worth the 5 seconds to check:

Is the radiator full of fluid?

 

Make sure ur head gasket isnt broken or anything by when you start your car slowly open your radiator cap till it burps then check for bubbles in your radiator and let it run for a little with the cap off because if theres air in your cooling system the stem is going to rise and throw of your gauge. And btw when you do get ur problem fixed switch your t-stat to 180 or 190...at 160 your just gonna get sludge and wear

 

So here is what it was.... A few months back I swapped all the interior and tail light wiring to an 87 GTA harness because I wanted to use my 140 Cluster. Well there must be something different in that 87 harness and the original 85 engine harness. My stock gauge was off my 40 degrees. So I installed a mechanical temp gauge and it stays between 170 and 180 with a 180 thermostat. Thanks for the reply's everyone

 

there is a difference between '85 and '87 clusters,
they were made by different suppliers;'85 back by AC
delco,most '86 up by nippondenso-apparently the
senders are different between the two...

 

Yes I know there is a difference. Originally I had all the stock 85 interior wiring and 85 gauge cluster. I swapped it all for the 87 wiring and 87 gauge cluster. So that left the only difference being between the engine and interior wiring.

 

While you guys are talking about cooling, I tried to run mine with cap off to make sure it is sucking into hose like it is supposed to do but it just spews and bubbles out. Any ideas why

 

It bubbles while it's cold, or while it's hot?

 

As soon as I start it. In fact as I am cranking it over. It is like it is just full of pressure or something

 

It also heats up really quikly

 

Check for a leaking head gasket.

 

As far as my oil goes. It isn't milky. It doenst really overheat I don't think. I have not driven it a lot though. I just got it. I has been changed to a crbed motor so a lot of crap in it right now. I don't know if correct water pump. I will check thermostat. Top hose get presurrized but take a long time to lose it. It heats to about 230 and then just sits at that temp. But it only takes about 5 to 10 minutes to get there. I don't know if guage is right. I will buy aux tommorow and hook it up. Just think that it is weird that when I crank it over it spews out of hole when cap is off.

 

I'm with ASE doc here. If it climbs on the highway I'd say it's lean.