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Mine hit 270* sitting in traffic today. It scared the SH*T out of me. I went down a side street to get the car moving. I have a 180* thermostat in it. But im not sure whats going on here. Now I came to a sudden stop after giving it a pretty hard full boost blast. But should it get that high? Once its gets moving again, it goes back down to the 200 mark. Let me know your thoughts.

Sounds like the fans are not coming on. Turn the AC on and see if the fans come on.

I keep a manual high speed fan override and have it running whenever I'm consistently below 45mph. I hit 185 most of the time, and no more than 195-200 on the hottest summer days.

Not sure what t-stat I have, never checked since getting the car.

My pump crapped out when it got that high. Replaced it, nothing about 200 anymore.

270* is engine blowing territory, and count yourself among the fortunate that it survived. It sounds like there is something with the fans not switching on like they should. If you turn on the A/C, do the fans still come on? The fans should be on by 225*, and definitely should be on high. I am curious what the coolant temp sensor is saying to the computer.

Definitely sounds like an issue with the fans. Also, make sure the radiator and evaporator aren't plugged with dead bugs, dust, and other debris. Could be a combination of things. Wouldn't hurt to take a low power pressure washer to them just to clear the crud out, just be really careful to not damage the fins.

Well did a leak down test on the car, not good. The center front cylinder (not sure on cylinder numbers on these motors) spark plug electrode is white in color. Also was low on antifreeze. Are these engines known for head gasket problems? Cuz thats what it appears to be at this point. Fans come on. A 180* stat was just put in a week or two ago, and the coolant was flushed. Not real happy with the findings.....

Head gasket? No. Lower Intake Manifold gasket failures? Yes. Usually caused when the Extended life coolant gets contaminated <very easy BTW> and starts eating away the gasket. Usually when they fail, they like to dump coolant in the oil. There is plenty of write ups that can guide you through the process if you like to turn a wrench or two <mod list makes me suspect you do>. Fix it, flush the coolant system, put in different type of coolant, and if there is no collateral damage from the leak, you are all set to go. You also may wish to make sure that your oil is not full of coolant.

RJolly87 wrote:Head gasket? No. Lower Intake Manifold gasket failures? Yes. Usually caused when the Extended life coolant gets contaminated <very easy BTW> and starts eating away the gasket. Usually when they fail, they like to dump coolant in the oil. There is plenty of write ups that can guide you through the process if you like to turn a wrench or two <mod list makes me suspect you do>. Fix it, flush the coolant system, put in different type of coolant, and if there is no collateral damage from the leak, you are all set to go. You also may wish to make sure that your oil is not full of coolant.

LIM gasket was changed less than 1000 miles ago along with brand new coolant. The higher temp issue started before the LIM change and coolant flush (thats why I did it) The leakdown test stears me towards head gasket failure.

How fast they leak down? You sure you had both valves fully closed? Did you do a compression test too?

As he said before, head gasket problems are nearly unheard of, although it isn't impossible.

Just got the car back together. Heads were milled, hot tanks and magnafluxed. Temp now stays @ 200 and doesnt climb. Thanks everyone.

Interesting. Were the gaskets obviously failed? That is honestly a rare occurrence unless you have a turbo and pretty big boost.

00Beast wrote:Interesting. Were the gaskets obviously failed? That is honestly a rare occurrence unless you have a turbo and pretty big boost.

The gaskets did'nt "obviously" fail, however the heads were milled .006" So the heads were not completely flat. I understand head gaskets dont go under low boost, but im not sure what the previous owner has done? The car appears to be well maintained and old registrations cards make me believe the couple who had owned it were older, it still doesn't mean it didn't have a smaller pulley, etc....I still have driving to do until im satisfied. I only have about 30 miles on since its been back together. However so far, so good.