heres the deal...my 94 ZF runs great most of the time, but sometimes when the weather is warm that thing just heats up like crazy. i have a manual fan switch but that doesnt help much. it gets up to 230 and then starts having heat detonation/stuttering/surging when i get on the throttle.. it cools down once i get it up to higher speeds, but this seems abnormal. i had it in a parade with the fans running and this sucker heated up to 250 and started stuttering so bad it was barely driveable, and the idle was jumping from 500 to 1500. please help? bad water pump? :( :cry

 

If it got that hot and started sputtering..........Im afraid it might be too late :smash:
:nopity
Its curtains and violins- sorry dude. you need to pull it over before it gets to 235 because it will rise a bit once you shut it down.

Mine was gettin like that, not all the fans or water wetter in the world would keep it cool in traffic with the ac on. I finally took the radiator out and raked the leaves, had it professionally cleaned and flushed. Cost about $60. Now the temp needle looks broken, barely climbs over 1/3 the way on the hottest day withthe AC on and solid traffic.
Check the oil and the exhaust for water.

 

First try pulling your radiator shroud and cleaning your radiator enclosure and radiator fins.....you can find a ton of past Forum archived step-by-step instructions on this.

If that doesn't help I don't care what anybody says about running 100% water, water wetter, etc., etc., etc.....

I would recommend possibly having your radiator flushed as Gus recommended or do what I did...I recently installed a new 2 row all-aluminum radiator.....see the photo in my profile.

Mine is a generic that takes quite alot of modifying both radiator and shroud :smash: :smash: :smash: to get it to fit (not for the timid), but it works great...dropped me during stop and go at over 100F ambient to max 215F coolant temp. It averages about 187F or lower highway.

I have a racing high-stall automatic and I have a tranny cooler mounted between my radiator and fans also rated for a 24,000 lb tow. I have it set to pre-cool the tranny fluid before it goes into the radiator since I have it behind the radiator......I put it here since the only other place is basically in front of the AC condenser and this would effect my AC cooling (never in a black-on-black).

Anyway, with this my tranny never gets over 215F and most of the time is between 203 and 208F.

Hope this helps....good luck :D


[Modified by 95BLKVette, 9:59 PM 7/16/2002]

 

well first check for coolant in the oil, unless that was a one time deal and youve driven it w/o any problems since then you could have a blown head gasket. Also take a look at the weep hole on the water pump, at first sign of moisture remove it before it pukes on your opti.

If youre lucky and you dont have a blown gasket there are things you can do to help it.

1. remove radiator and clean the front, flush and refill with a bottle of water wetter
2. new 160 thermostat
3. the only permanent fix is to have the main fan reprogrammed to turn on at 195 if your manual switch isnt connected to the main

If all this doesnt get them down then you have a real problem.

 

Hello,

All good tips. I would pull the top off the air dam and clean both the A/C condensor and radiator. If the A/C condensor is clogged, less air to the radiator. If there is really a lot of garbage in the radiator, pull it and clean it. If not too bad, blow it out, clean the area up.

Make sure you have all the air dam parts, ie bottom plastic pieces, left, right, center. I have seen these removed from some cars.

Flush radiator, (if you didn't send it to a radiator shop), 50/50 mix with "Water Wetter". (I like the Redline stuff). Check all hoses to insure they are not soft or "tacky".

Make darn sure both fans work. You should be able to start the car, turn on the A/C, both fans should run, and you should step to the sides and feel lots of air coming out from underneath the car. Look at each fan. Try to sense if both are pulling equal amounts of air. (Believe they run about 2200 RPM) Check them again at operating temperature. They can be very sneaky, work for a while, then quit, or not work quite as much. Personal experience.

Replace thermostat. If you want to test it, heat some water, use a thermometer, and see when it opens. For around $10 you can buy the GM product or whatever you want. I also replaced my engine coolant temp sensor while in the area. Ohm check showed slightly off. Another $10.

If your car is stock, the stock system should work.

Last week, 97degrees, traffic, my 90's temp gauge was dead in the middle. Cooling system is stock, along with everything else.

How did the car run the next day? Still RPM problem? Another issue.

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