OK slap me if you want not sure if I'm posting this in the right place but here goes.... Can anyone tell me why when my 89 RS gets HOT (above 220 mark) everything electrical under the hood shuts down. It takes several hours of cool down time for the car to recover. This is getting really annoying and the wife says if I don't fix it soon the car goes ! Help, I really enjoy this car and would hate to let it go because of something stupid!

 

Same problem

SOMEBODY HELP US

 

Shot from left feild, but how old are your batteries? I'm thinking they may be weak to begin with, and when the radiator heats up, it's actually boiling the battery too? Sits right between the rad. and over flow so kind of makes sense?

 

HERE IS THE UPDATE:

WIRING SEEMS TO BE THE ISSUE

Last Night; I took it for a test run while going to pick up a new ICM, well let me tell you it was not the ICM causing the shut down. It shut down again and I was stuck on the road until late

I was really ready to junk the car, but the body is great and when it does run it is a real Stallion on the road, so I am

I did notice the wiring for the coil was a little stripped. ( that could be the cause(don't think so yet).

Tonight I will go and get a battery with somewhere between 810 - 925 cold crancking amps.

This weekend I will install a new starter.

If that does not change this I will go back to the wiring connected to the coil next to the ICM.

 

Hey, before, you go and throw more money (and time on the side of the road) at it, how old is the battery? Is it due on it's life. There are some test you could do.

Like I sad I'm just throwing out a shot in dark on that one. It defately would be something that dosen't like heat and that was my first thought, and since it takes a long time to cool off, made some sense.

I've had my fair share of ICMs go bad in my time, but there's usually an indication at all times, misfiring or something like that.

 

Today, I am doing a load test on the Battery and replacing if necessary

 

There ya go, now we speak a mutual language.

 

Make it happen again, and when it does, check for spark. Something is causing you to loose either spark or fuel (possibly both, but unlikely). It won't solve your problem, but it narrows it down a bit.

My money is on the ignition coil. When I coil gets flaky and goes half bad, it's usually temperature sensitive, too. Being in back of the engine bay, on top of the engine, it's also a slow cooling part, which would explain the hours of cooldown required.

 

Yes, I am going to check the coil.

Update:

I have changed the ICM and put a new Battery (Champanion 925 amp) car runs better but is still shutting off when hot.

Tomorrow I am going to check the Cat Converter.

I was running it last night and it seems to be overheating, when I turn the AC on it brings the temperture down. So, my thought is something is not letting the air flow out.

 

Both of those are V6 cars?
In my recent headaches, I've only had over'boiling' as it were, where stop and go and slow moving 'crap'ic causes temps to quickly fester underhood. Driving freeway speeds on cool days keeps temps at bay...if overheating for me, 15 to 30 minutes allows a good partial cooldown and the car will run. Last overheat, there wasn't enough time to wait, and the key didn't offer any startup so I walked back to my work/apart location leaving the car parked off the street. It started once I got back to it after work. I'd say there does appear to be a protection circuit in a critical overheat to avoid severe damage it appears.

I had an 88 Deville where the waterpump was failing and the weep hole was a clear indication. In my Firebird, the gaskets are in dire need of replacement but haven't been able to afford a replacement at present and the heads are suspect of warping and a compression test suggested from my mechanic.

The Deville seemed to exhibit different overheat characteristics and also presented a Shutdown Engine telltale in extreme overheat, so you clearly knew when you needed to park and shut the engine down.
Either way, I keep the econ fans on and venting the hot air thru the dash...on hot days it doesn't help you much, but it does keep that air off the engine.

I don't use my A/C because it has no charge on it...blows hot anyway.
Currently my radiator fans don't come on and I'd had my Cadillacs' fans tested before to make sure it wasn't a fault at the fan, of which I'm thinking the same for my Firebird
Bill

 

I will be checking my whole cooling system to include thermostat, fan and coils.

 

When U say everything shuts down--what exactly do U mean?

Do U mean there is no electrical power to anything under the hood, or do U mean the engine dies and won't run?

When it does shut down--get a volt meter and see if U have 12 volts to the coil or other places--if U do and it still does not run, it may be the control module in the dist or maybe the coil.

I highle recommend U do a little basic trouble shooting before U just strart throwing parts and money at it!

Give us some more info and we may be able to help U out.

 

Okay here it goes:

After driving about an hour the car shuts off / engine stops; it allows me to put it in park and turn it back on and it starts right back up; I can do this several times before it won't let me do it anymore then I have to wait about 30 min or more before she will start again.

I was definitly thinking coil issues, the other day I replaced the ICM; I don't believe there is an issue with the ECM.

Something is blocking the air flow which is telling the computer to shut off, again coming back to the cooling system because the thermostat reading shoots up high after driving about 45 min until I turn on the Air Conditioner then it cools off; I guess because the fan is running harder.

So, besides the coil I am thinking thermostat; again in the morning I will be running a few more diagnostic test on her.

CHUCKY! MUST BE UNDER THE HOOD OF MY CAR MESSING WITH HER

 

The quick fix would be to ground the fan relay so it runs all the time. I believe it is the green wire with a tracer stripe at the fan relay usually located by the battery. Do a search on "grounding cooling fan relay"

Single fan or dual fan?

 

How hot does it get?

If your cooling system is stock, they normally get quite warm before the fan even kicks on. Before I changed to a cooler fan switch, I used to just turn the ac on to keep it cooler. If the weather is warm enough for the car to get warm, it's probably warm enough for ac.

Installing a cooler fan switch come on sooner is a better solution, of course, but turning on the ac is only a flip of a switch.

 

I get past the 220 to 230/40 reading on the stock temp guage and then try to let mine cool. In a hurry, I'll remove the overflow container cap to allow some cooling quicker, not sure that's always a good idea, but the other day even after a short run I removed the radiator cap after cooling with water (poured over inlet on pass side) and it still bubbled out under pressure, but after that initially the fluid level went WAY down so I needed to refill the radiator and resevior. I ran the A/C in all modes when I last got to 220+....No fan action. I'm told there is a 20 amp ATC? fuse as well to check, but the normal fuse bay appears good...faulty antenna was removed and fuses rechecked....still no fans

I would like to figure out the radiator's sensor box that taps thru the fins in back...came with my used replacement radiator but not hooked up to anything....Looks like a way to control the fans or read the temp...no idea for sure though

BILL

 

If it's what I think you're talking about, it is the low coolant sensor. The only cars that ever made use of it were the GTA's with the digital dash. Maybe the camaro berlinetta too, but that's just a guess.

Regarding the fans, they get their power from a fusible link. Not sure where off the top of my head, but if you follow the wires back from the cooling fan relays, you'll find it. I wouldn't use your ac until you get the fans fixed, either. Without fans, the system will get over pressure, and your refrigerant will be vented from the relief valve in the back of the compressor.

 

UPDATE:

Well Guys, the Mechanic states that my Water Pump is shot.

I'm wondering if it was just the thermostat> Would I not have more of an issue with the car if the water pump was shot?

 

Normally some coolant loss through the weep vent and if bad enough a bit of noise, rubbing or rattling emitted.

What made hime say W/P was bad?

Would back up my hteroy a little bit.

 

He stated a pressure test was performed and found the water pump shot.

 

Well, it may need replaced, BUT I SERIOUSLY DOUBT IT IS CAUSING THE PROBLEMS U ARE DESCRIBING!!!

 

umm, how many threads in how many forums are pouding the same issue for you tamay?


I don't htink the W/P is the culpret, and he pressure tested could just mean the gasket leaked?

 

One of the reasons I started a thread is for some visual indicators, as they say, a pic speaks a thousand words. I think components have shuffled around over the course of only a few models and years, for example, I see the battery changing sides, along with the air inlet depending on the engine, usually. Anyway, I was thinking aftermarket...interesting. I had pics on my other PC but that one fell victim to a Trojan and this one is bogged down by something [Pentium3 w/ 500 MHz book PC]

I'll get pics of my car that may help as well.
Bill