VenkmanP

Good theory, but for one flaw - his EEPROM is soldered to the circuit board. Mine isn't, because I had it removed and socketed.

Also, if somebody had computer problems on an older computer, and reused the old PROM, that would be a poor repair job. At the very least they should reburn it.

bogus

on 90-93, the EPROM is removable... I misread the year, read 95 as 93... reading to quick.

the chip does not need to be reburned, a power programmer can check and update accordingly.

nitronick

I don't know if this applies in this case, and this was in a Chevy truck, but I have had problems in the past with aftermarket temp sensors from the big parts houses. O'Reilly, Autozone, etc. I went through three of them reading high temps until I bought one from the GM parts dept. I was getting readings as much as 35 degrees over the actual temps.

REDC4CORVETTE

Is the trans TQ converter in good shape?
Is the engine pinging on acceleration.
How many miles on this car?
When the A/C comes on does the 2nd fan come on?
I know you installed a Switch try running it from the time you start the car.
Are the top or bottom radiator hoses colapsing?
Are your low coolent or overheat lights comming on?
Does the engine idle at 600 rpms.
Does it get hot above 55 mph?if it does you most likely have a head gasket problem,or a raidator hose colapsing most after market hoses don't have the spring inside them .
Do you have a laser heat gun ?
shoot the block should be around 180 to 220, the exaust should read 900 to around 1250.
Raidator should be hot at the top cooler at the bottom.
Reverse flow system.
Have you done a compression test?
Need more information.

albertlsmith

When it overheats, the water boils and you can hear it inside the car. The tempratures hit 250 and above, when the needle pegs out on the analog guage and the digital reads "Too High" or something like that. I didn't accept the new computer because it did not fix the problem so I told the dealers to keep that. I can't drive the car around the block after it has been idling for awhile because if I put it in gear, the temprature will rise and peg out very quickly.

albertlsmith

The car has 220,000 miles on it, the motor has been rebuilt at around 150k.
The second fan does come on with the AC but it makes the car heat up faster as if it were in gear.
I have not installed a switch.
I have not noticed the engine running at 600rpms, the motor actually runs fine, just overheats.
It doesn't get hot on the freeway as long as I'm doing 55mph or more. It gets hot when I stop.
I have not done a compression test yet since the dealer wanted $100 to do it after I spent over $1300 already for them to diagnose the problem. That will be my next move I suppose. Thanks for your posting.

Chris_G

I'm wondering about your coolant mixture. Is it 50/50 as it should be? More is not better.

I had that problem with my 94 and got the mixture to 50/50 and it seems to be OK now.

Good luck

crheinish

Both fans should be running with the A/C on. You say it runs cool on the highway but overheats when at a light. That would indicate an airflow problem across the radiator. How cool on the highway? Verify both fans operate, primary will engage @ 228*. Secondary will engage with the A/C on.

VenkmanP

Sounds like head gasket and/or damaged head.

greenvette95

Get a new radiator cap. No joke.....

bogus

that's where I'm leaning to...

ZRWON

you might find these sites of interest...sounds familar... http://www.imcool.com/articles/antif...l-macs2001.htm and http://www.imcool.com/articles/antif...ohnbrunner.htm Also, you might want to do a search re DEX COOL. I understand there's a class action suit in the works because of engine problems and contradictary statements by GM/Texaco.

albertlsmith

I'm leaning towards the head gasket too, but wouldn't I have water leaking on the ground if that were the case. I really haven't noticed any water leakage, but I'll take a look. It's just that I hadn't looked for water before. Is it possible that the shaft that turns the water pump has gone bad and if so, how would I diagnose it?

84whitevette

Albertsmith,
Usually the coolant will leak into the oil not onto the ground when the headgasket fails. Check the oil to see if there is coolant mixed with it. If you don't see any, it may be still occurring to a mild degree. A compression test as recommended by others will help find your answer.

CFI-EFI

It can also go into the cylinders. If there is enough, it will be evidenced as white "smoke".

RACE ON!!!

albertlsmith

Thanks for the help, guys! It's not fixed yet, but I have a better idea of where to start. I'll get back to you guys and let you know how it goes. Again, Thanks!

SilverBeast

Radiator could be clogged up internally. Cheap to rod it and that may fix it.