jmasek

OK so I have my 94 LE2 motor done and I'm having some problems with it running hot, so SES light or anything, seems to run good but it get to about the 240 degree mark on the gauge when I'm driving it, comes down towards middle line if I stop and sit and the fans run, has a 160 hypertech thermostat, 30 lb injecters, new water pump, new opti, all lower end new with mahle pistons, it is not tuned yet though as it is going to a buddy in Houston and be tuned down there, any ideas?

SS RRR

iTrader: (2)

Running hot usually means there is a lack of coolant in the engine. Is the air dam still on?

qc97z

iTrader: (9)

X 2. Check to make sure both the radiator and overflow are full, and the system has been bled properly.
And make sure it's got an air dam. You CANNOT go without it.

02v8ta

iTrader: (8)

X2 on the air damn, that tiny little plastic thing is a bitch if you take it off

jmasek

If by air dam you mean the plastic shield on the front of the radiator/condenser yeah it is in there. I was thinking air pocket too it seems really gurgle about the time the thermostat opens and if I shut it off it will suck some coolant back in but I've tried this probably 10 times (I have a funnel for the radiator neck so it doesn't pressurize the system to bleed), and it still seems to be pushing air, any hints on how to get trapped air out if there is more?

ZFreie

If you don't have the fans programmed to come on sooner the 160* t-stat isnt gonna cut it by its self.

Also, park the car up hill, nose higher then the back and then try bleeding the cooling system again.

Formula413

iTrader: (1)

+1 on air in the system, I had my coolant drained a few weeks ago to fix a few things and I just followed the procedure listed in the owner's manual to refill. Open both the bleeders, add coolant to the radiator until it comes out the bleeders, then close them (none ever came out the higher of the two bleeders, just the one on the thermostat housing), keep filling to top of radiator, put the cap back on, run engine for four minutes, refill radiator.

One thing that makes it easier to chase the air out is if your low coolant sensor works. They usually don't because they are fouled with Dexcool. I cleaned mine when the coolant was out and it works now. When the sensor works you can watch for the light on the dash, and as soon as you see it stop the car and top off the radiator. Also make sure the reservoir doesn't run dry.

jmasek

Ok so i'm about positive that it is bled out and when running down the road it will go to right under the red( so 250ish) on the gauge then when the fans come on or you just cruising down the hwy it sits between the middle and 3/ line. If you stop and take off again it repeats this process. It will idle around the 3/4 mark on the gauge which I think is high but my temp gun only shows the motor is at 215 at the hottest, is the gauge off? Anyone else have this problem? I put in a new GM sensor for the gauge also and no change. One other note the fan doesn't kick on until its right under the red either and I've found they're supposed to come on at 226, second fan at 235 and the second has never came on yet, cools with the first.

Formula413

iTrader: (1)

Do you have any kind of scanner to see what temp the computer is reading? The sender for the gauge might be wrong, there is a different sender for the PCM

jmasek

Yeah I have a scanner I'll have to take it home and check that because this is driving me nuts, car doesn't act hot or smell like its melting either, and even though it has a 160 thermostat and it hasn't been tuned shouldn't make it run hot right?

02v8ta

iTrader: (8)

Correct. It shold run at normal temp and if anything take longer to get there.

Formula413

iTrader: (1)

If you're able to confirm the overheating issue with a scanner you might want to try putting your stock thermostat back in just to rule out the 160* stat being defective.

I have also heard that the radiator itself can be clogged by dexcool, FWIW. Keep checking the simple stuff first though.