Kaps

Hey, Ive checked all the overheating faqs and searched, Did all the tests but the cap, I believe its ok, but am going out tomorro and getting a new one anyway.

At the moment I do not have a air dam, but it was ripped off by the driveway recently after my problem started. I replaced the heater core, thermostat, and radiator all within the last six months. A new water pump was put on about 2yrs ago, all hoses are fine and not collapsing.

It overheats anywhere anytime, parked, highway, around town, everywhere. Are there any sensors that could be making it overheat? Heard maybe the oxegen sensor or something else I cant think of right now, Or anything else you guys could think of? Its not throwing any codes

Its a 88 GTA 5.7 TPI

(note to mods: if this doesnt belong in here please move it or tell me how to, just figured TPI guys might know more about the sensors and what not, sorry if its doesnt belong)

SanitariumTour0

start with the airdam ASAP. The airdam is very important to cooling under the hood because it is really the only way that air is directed into the engine bay. After that you can go with a 180* thermostat. These 2 things should help considerably and then let us know if you still have problems. Both of these should cost you no more than around 40 bucks if you go to a nearby parts store. Oops sorry. I forgot you already got the thermo. How bad is overheating to you? I have a not so good radiator and a new 180* thermo but I still see my heat around 200 most of the time. Let us know how bad the overheating is and then maybe we can go from there.

Kaps

Wow, I made a good decision, picked up a 180F thermostat!! The thermostat is working, tested before put in, the radiator was replaced like 2 weeks ago, tested at the shop before install. The overheating is bad, it will climb upto near redline in about 10-15 minutes of driving, or parked with the hood open, then I shut off the car before it proceeds to redline, it doesnt stop I dont think, I never actually let it redline though. That was with the air dam on too. Ordering one from GM tomorro after I pick up the new radiator cap. Anymore info need just ask...

Thanks

Plus checked for signs of head problems coolant/oil mixes, none noticed

Also, under the belief that timming is controlled by the CPU, is this true? Never checked it and dont know what is should be at.

The have been no modifications to the stock form (besides for replacement parts) of this car besides for an Accel: coil, cap and rotor wires, and plugs.

SanitariumTour0

hmmm....well I am by no means an expert with cars because i started loving cars when i got my camaro i wrecked. But anyways...timing COULD be a problem. I wouldnt really know tho but I did have a problem when i had my camaro that my timing was WAY off and it made the headers glow red hot. That most likely isnt your problem but hopefully someone else will chime in cuz im just in the learning process of most things here. IM getting really good with the performance aspect but the troubleshooting problems I absolutely hate. o well...good luck

Kaps

Thanks for giving it a shot, ANYONE else? ANY ideas?

bigals87z28

ill throw in my .02

you NEED that air dam, its very important
the 180 stat will help.
Do you fans go on at all? you could have a relay problem, or a temp switch problem.
Do this, infront of the radiator, leaves and what not gets trapped up there, and can cause poor cooling... Check it out. I bet you have some stuff you can scoop out. you might need to take out the radiator, but i think you can get at it from under. If you really wana get all of that gunk out, take out the radiator and while you have it out, flush it out with a hose. When was the last time you put new anti freeze in it? This would be a little better suited for the cooling board. I hope that gave ya some tips on how to fix this. Your overheating is pretty bad. 10-15 mins... check your lower hose. Make sure that the spring is inside it. start with the easy stuff, and work to the hard stuff.

Kaps

Thanks for the suggestions, Ive spent the past 3hrs reading everyone elses problems, maybe I have some thing to look for.

To address your suggestions, The one fan comes on, I have watched it, I dont believe I have let the temp climb high enough to make sure the 2nd one comes on, something like 210+ degrees? The motor should have no problem idling for 10-15 min in park, therfore the air dam wouldnt come into play yet, right? (but I am getting a new one as fast as GM gets one in) When I replaced the radiator a few weeks ago, the car has been parked ever since due to a headache, if you want to read my nightmare go here,
https://www.thirdgen.org/techbb2/sho...hreadid=176087
When I had the radiator out, I made sure to clean up all the crap so much that my friend was making fun of me. Last time I changed my fluid, known the past 2 owners personally, the radiator was repaired about 2.5yrs ago, and was flushed. I have been either leaking coolant due to thermostat and boiling for about 3-5months now, so have been topping it off, looks nice and clean. Any tips as to how to flush properly DIY??

How do you move the thread to cooling board? Thanks for any and all input,, need ANY help I can get

Once again ANY questions or comments welcome!!

Morley

If you are having to keep adding coolant you might have a blown head gasket. Have you looked at the exhaust to see if there is any vapor (steam) coming out of it?

Kaps

I think I might have confused/misworded that. I had to add coolant when I changed the heater core (4months ago)
changed the radiator (2weeks ago) and when the thermostat housing was leaking, now fixed. Now coolant level seems to be steady. Checked oil and coolant to see if I had a milkshake looks good...

Morley

You can blow a head gasket and not mix oil and water.

Ed Maher

I can't really make heads or tails from your timeline of when the problem started vs. when you replaced all those various things. ANYTHING that is older than when the problem started is suspect.

I do notice you say the water pump is 2 years old. If it was a rebuilt piece, then it is VERY suspect. A common problem on old WPs can be that the impeller wears out from sediment / rust in the coolant, leaving you with poor cooling. Not going to happen in 2 years, but a generic rebuild could be using an original 87 core with 500k miles on it. You never know.

Another thing to think of is the antifreeze - water ratio. Antifreeze is a horrible cooling medium. Now not so horrible that the car woud overheat just idling, but even under moderate load i've seen heavy antifreeze mixes cause problems.

The fact that it will overheat while idling is weird. That would make me think the thermostat was stuck. I can't figure out if you've replaced it recently or not though from your posts. I mean, it's damn hard to overheat an idling engine, something is grossly wrong for that to happen, unless the fan doesn't work. I see you say it does, however just because it is moving doesn't mean it is working 100%. You should have a veritable tornado under the hood with the fan on.

And of course there is always any combination of things at the same time. A sticky thermostat, weak fan and leaking radiator cap combined would leave you all messed up.

Fire"Dutch"Bird

iTrader: (1)

Redline WaterWetter might help a little.
And don't use to much anti-freeze,just about 15% will do the job!

Kaps

Hey, got new cap, it leaks, so I called up Pontiac for the air dam and for the radiator cap
$15 radiator cap
$52 air dam!?
how did you guys get them for $24??
Also checked my coolant ratio, 30-35% coolant, what would be safe for winters in jersey?

dave89gta

How hot are you talkin that your car gets?
I know the TPI engines can get really really hot, mine is around 220* just in city driving. I plan on getting a lower thermostat.

As far as I knew, hot was normal for TPI engines.

Kaps

Damn near redline hot, not too interested in cracking my block so I kill it before it gets that hot. Have the digital GTA dash so the block right before the "red line" block.

I can squeeze my upper hose about 1/4 inch, how hard is it sopposed to be when the thermostat is open?

Ed Maher

You're not checking much by squeezing the upper radiator hose. If the thermostat is older than your problem, i'd simply replace it. Too cheap and easy not too.

and dont buy a radiator cap for $15 at a dealer when you can get it for 5 at a parts store.

Coolant ratio would not be causing it to overheat at idle.

Kaps

The one I got from the parts store doesnt fit too well and leaks, and I triple checked the p/n. The thermostat was changed yesturday. Any info/pn on air dam $?

WS6Formula350

I don't remember anyone saying this but have you replaced the temp. senor that tells your gauge what temp. the car is at. Maybe your getting a false reading from the gauge.

92 heritage z28

hot was normal for tpi engines, the general made em that way to help em pass epa ratings.

bigals87z28

check your lower hose. if that thing is jammed shut... red line in 15 mins sounds about right. There is a slight chance that your temp sensor and gauge isnt right. The stock gauges arent really that good at telling anything, they just give you a rough idea. I dont know how accurate the digi gauges are, but probably just as good as the rest of them.
The Waterwetter isnt gunna do much. That only helps if your car has a moderate cooling problem, and you need a little help... then you drop that in. In this case, there is something wrong with this mans cooling system.
Your not to far from me (30-40 mins). If ya need some help, ill come up and help ya if you want me too. Just wish this weather would clear up so we can have the big meet down in Toms River this weekend.