96 Lumina Low Coolant/overheating (now with pics!)

[glassvial]

Just (trying) to finish up a LIM gasket job on a 96 Lumina 3100 motor, thought I had the system all bled out and all, but when it actually runs (drives, road test) the SOB throws a low coolant light and eventually gets up to a hot light being on. Let me be clear here, I have replaced:

 

LIM gaskets

UIM gaskets

fuel injector o-rings

every single coolant hose under the hood

water pump

thermostat (tested before install)

power-flushed out the radiator, flowed 100% clean with a pressure washer (straight water, no chem)

heater core

 

I'm about ready to put bullet in this thing and put it out of its misery, unless someone has some suggestions for me. Thanks.

 

See page 4 for pics.

[slick]

Have you tried re-bleeding the system again, with the heater on while running? Generally, I can always add more fluid once the vehicle is running.

[glassvial]

Bled the system every time with the heat (temp) on max and blower speed on 1.

[glassvial]

Anybody else have any ideas? Did a radiator swap tonight just for the hell of it, didn't help (didn't think it would but grabbing at straws at this point). Been trying to bleed the damn system and the coolant just seems to keep backing up into the overill (which is now quite full) and the temp gauge gets very very high. It's not head gaskets, no white smoke in the exhaust, oil is clean, no leaks that I can find.

[glassvial]

Nevermind, finally got the SOB. Took jacking the car up in the front and 5 full coolant bleed cycles to finally get all the damn air out.

[glassvial]

Ok nevermind, I don't got it, went out for a slightly longer spin last night and she overheated again, full overfill tank. The coolant pressure test did not seem to indicate a head gasket problem, so what else could it possibly be?

[Crazy K]

remove the tstat, and drill a small hole in it. like barely 1/16th of an inch. this will allow air to be purged. whenever I do coolant on a 3100, I backfill the system through the heatercore hoses and through the ecm temp sender (by the tstat) with a funnel, and then assemble and start the car.

 

right now, if you were to pull the ecm temp sensor, you might find air behind it.

[glassvial]

remove the tstat, and drill a small hole in it. like barely 1/16th of an inch. this will allow air to be purged. whenever I do coolant on a 3100, I backfill the system through the heatercore hoses and through the ecm temp sender (by the tstat) with a funnel, and then assemble and start the car.

 

right now, if you were to pull the ecm temp sensor, you might find air behind it.

Any place to drill that hole in the stat or is anywhere good? Funny you mention putting fluid in the heater core hose, because that's exactly what we did yesterday to try to get some in there (damn thing). So you're saying to also put coolant in where the coolant temperature sensor goes also (I think that's what you mean by the ecm temp sensor, no?)

[glassvial]

Ok so drilled some holes in the stat filled it up again bled it again took it for a spin on the expressway for awhile, temp fluctuated anywhere from around 1/4 to 3/4 (give or take?) so is this progress?

[slick]

Seems a bit more like normal. On rachel's 95 regal, it will get up to about the 3/4 mark, then drop back down to 1/2 or so, and fluctuate in that range.

[Crazy K]

one single SMALL hole, as high as you can on the tstat flange, and making sure it faces up.

 

and you got the right sensor.

 

How many holes and how big did you drill???

 

[glassvial]

My buddy thought that 1 small hole wasn't enough (he doesn't listen very well) so we did 2, 3/32's I *think* is the drill bit we used (hey if I gotta buy a new stat that's no big deal it's only $7). We took the temp sensor out and filled via the radiator and fluid immediately came out of it (the hole were the sensor was) so I'd there there couldn't be that much air behind it if that's the case.

[glassvial]

Seems a bit more like normal. On rachel's 95 regal, it will get up to about the 3/4 mark, then drop back down to 1/2 or so, and fluctuate in that range.

This is going anywhere from (roughly) 1/4 to 3/4 now. I need a video camera mounted to watch it when I drive so I can put it on youtube or something

[Crazy K]

even with the tiny tiny hole in mine... the water blasts through it with a solid heavy stream. a single 1/64th hole would work best... but would be too hard to do, unless you have such a bit.

 

the point of the hole is to allow air caught behind the tstat to pass, with only a minuscule amount of water passing. it is not intended to allow significant amounts of coolant to pass.

 

 

I would leave it be for now, and maybe when fall comes around, get that Tstat changed for one properly drilled.

[glassvial]

even with the tiny tiny hole in mine... the water blasts through it with a solid heavy stream. a single 1/64th hole would work best... but would be too hard to do, unless you have such a bit.

 

the point of the hole is to allow air caught behind the tstat to pass, with only a minuscule amount of water passing. it is not intended to allow significant amounts of coolant to pass.

 

I would leave it be for now, and maybe when fall comes around, get that Tstat changed for one properly drilled.

Well the car certainly has good heat (thanks to the new heater core) so that's no problem. Don't have such a bit, only 1/16 and 5/64 up from there. Guess we're gonna try to bleed it again tmrw and see how she does. I'm not sure if this stupid car is ever going to get to the point of "jump in and go" status. If that's the case, I'll long be selling it by wintertime that's for sure.

 

Need to sell my 94, then sell this 96, then I got another 96 to sell, got a 98 lined up, and the 00 Buick waiting in the wings, too many!! And they're all w-body's too

[Crazy K]

you must be my doppleganger! j/k

 

you should not have to do more bleeding with the tstat holes. the air will now purge itself to the radiator. keep running teh car, but regularly check the radiator and add fluid. and to be safe, make sure your oil level isn't rising!

 

 

[glassvial]

Hmm, well, just when you thought it was safe...

 

Decided to take her out for a spin tonight. Didn't overheat, but the low coolant light did come on, temp fluctuated between 1/4 and 3/4 (mostly 1/2 to 3/4 though) and the reservoir was almost full (up from just over the cold mark before I started) and had big bubbles in it. I'm getting SO frustrated with this damn thing!

 

Any chance it's just something stupid like a bad coolant temp sensor, or maybe I need a new t-stat after all? Something just doesn't seem right here.

[slick]

Your still getting bubbles in the overflow tank? Sounds like a leak, or the system isn't at full pressure somewhere.

 

Have you checked your oil and trans fluid lately? How does it all look?

[glassvial]

I don't see any (external) leaks, oil and tranny fluid looked ok last I checked.

[Crazy K]

I don't see any (external) leaks, oil and tranny fluid looked ok last I checked.

ok, i suggest just keep driving and monitoring the problem, it may still be air bleeding from the system.

 

otherwise, check the temperature of the coolant using an external device, or scan the car to see if the ecm and guage temps match. my 95 has a 20 degree mismatch between the ecm and guage.

[LumiDriver]

I've been getting the exact same problem with my 95. It acts like it's burning coolant, but the oil and exhaust don't smell like it is. I was thinking LIM, but if it would've gone, it would have already by now. I add coolant about every 500+ miles, and it runs great! AC doesn't ever work even after I charge it.

 

I'm at a loss with my car. Too many things need to be done to it.

 

What would be the problem with the coolant thing?

[glassvial]

I don't see any (external) leaks, oil and tranny fluid looked ok last I checked.

ok, i suggest just keep driving and monitoring the problem, it may still be air bleeding from the system.

 

otherwise, check the temperature of the coolant using an external device, or scan the car to see if the ecm and guage temps match. my 95 has a 20 degree mismatch between the ecm and guage.

Ok will do. Not sure if the 'loan a tool' from autozone is sophisticated enough to do temp reads or not (I just snag it to clear codes as needed lol) 20* is quite a variance for yours, though.

 

Just checked outside on mine, coolant is just about the hot level in the overfill, even though it's been sitting for several hours. Hm.

[glassvial]

I've been getting the exact same problem with my 95. It acts like it's burning coolant, but the oil and exhaust don't smell like it is. I was thinking LIM, but if it would've gone, it would have already by now. I add coolant about every 500+ miles, and it runs great! AC doesn't ever work even after I charge it.

 

I'm at a loss with my car. Too many things need to be done to it.

 

What would be the problem with the coolant thing?

Nice hijack of my thread (j/k) If you're oil isn't milky, it's probably not LIM's. Doesn't sound like you've got a head gasket problem, either. A/C in my 96 doesn't work either, but I haven't tried charging it yet, and the blower selector doesn't work, even though I replaced the control unit, so I'm guessing there must be some sort of vacuum problem somewhere? Who knows, too much fun, too many problems to cram into one thread I suppose

[Crazy K]

if your cruise control doesn't work, it is definitly due to a vac failure.

 

find the vac ball behind the bumper on the drivers side front, and make sure the line is still attached, and that the check valve located below the mater sylinder is intact... etc etc. - they are on the same vac circuit.

[glassvial]

Cruise indeed does not work, but then again I have this white wire that came off somewhere and we haven't traced it out yet where the f it goes. Car decided to throw a P0441 code tonight (even more fun!) which is probably due to the vacuum problem. I think there's some sort of vacuum thing underneath the coil packs, didn't recall seeing one underneath the master cylinder, not sure what you're talking about the vac ball?

 

Also in regards to the original topic, the bitch overheated again tonight, had to get towed home...honestly starting to wonder if it's a bad (new) water pump, I can't think of anything else it could be at this point.

 

Maybe I should just start a new thread, 96 Lumina, multiple probs, help!