Cooling problem question

[Gatt9]

Hey all,

Having a minor issue with cooling. When the car's running and I'm driving, as long as the car's moving my engine temp stays around 180 degrees. If I've been driving for a bit, and then I'm stopped at a light, my engine temp shoots up over 210 degrees. Once I start moving again it goes down, but hangs around 195 degrees after it's shot up once.

I replaced the thermostat with a 180 degree. The waterpump and fan are at least 6 years old, can't tell if the fan's coming on.

Recently did headers, and my mechanic's trying to tell me that the fan won't turn on until 250 degrees and that the headers will make it do that. I'm thinking he's wrong, I'm thinking the fan should kick on at 195 since it doesn't get tuned until next Sat, and I don't think jet coated headers should do that.

Need some expert opinions here, the waterpump and fan are both pretty cheap, but if it's more likely one than the other, I'd rather start there.

Thanks all!

Edit: I did bleed the air with the scew when I did the thermostat and it started before that, and I recently switched from Dexcool to the green stuff, like 4 weeks ago, but it's been cold weather until this past week and a half.

[tkoforpresident]

Re: Cooling problem question

my 3.4 seems to do the same thing, i'm not sure if the fans kick in either.

[FirebirdGT]

Re: Cooling problem question

and I recently switched from Dexcool to the green stuff, like 4 weeks ago,

Well, that was a mistake. That should not be done, and I don't care how many "experts" say otherwise. Dex-cool is far superior, IF you take care if it and use the PROPER mix.

The year of the car might help also.

[Rob Bell]

Re: Cooling problem question

Your fans may be dead. I think the fan activation temp is around 220 or something. Def not 250. Turn on your AC to see if the fans come on. If they do then it may be a temp sensor issue. When they are running, see if your temp comes down. If it doesn't, or not by much, then you need to further test the fans. They may be running but not fast enough.

[bigbrian442]

Re: Cooling problem question

Stock settings on the fans turns them on at 221*F and off at 214*F. Once the motor is heat soaked from sitting at a light it would take a good while to get back down to the opening temp of the Tstat.

[landj]

Re: Cooling problem question

Yeah, my 3.4 takes a while to cool back down after reaching 220, usually the temperature gauge stays around midpoint for a few minutes before settling back down.

I have found that turning the AC on when it starts to heat up (even in the winter) will kick the fans on and keep the engine temp down.

[Gatt9]

Re: Cooling problem question

Thanks all!

Well, that was a mistake. That should not be done, and I don't care how many "experts" say otherwise. Dex-cool is far superior, IF you take care if it and use the PROPER mix.

The year of the car might help also.

I appriciate that Dexcool, scientifically, it superior to green. But I question my ability to maintain it properly, while the green stuff is easier.

It's a 1998 firebird, haven't modified the engine yet, just intake and exhaust.

Your fans may be dead. I think the fan activation temp is around 220 or something. Def not 250. Turn on your AC to see if the fans come on. If they do then it may be a temp sensor issue. When they are running, see if your temp comes down. If it doesn't, or not by much, then you need to further test the fans. They may be running but not fast enough.

I'll give that a shot Tuesday, that's the next time I'll be making a drive long enough to test.

I'm sure the AC turns the fans on, I've used it recently and it worked perfectly.

[nascar24jd]

Re: Cooling problem question

This is the exact reason I installed an SLP manual fan switch. Now, I control when the fan comes on and my car runs nice and cool.

Get one it is a great investment.

[Firebirdkid96]

Re: Cooling problem question

You don't need to spend the money on an SLP switch, you can make one yourself with some extra wire and a single-pole, double-throw switch. There's a write-up somewhere on this forum on how to do it, you just ground the switch, and then splice the two throws into two wires on the pass. side of the engine bay. If anyone's interested in this, I can take pics later. Just let me know.

[tkoforpresident]

Re: Cooling problem question

You don't need to spend the money on an SLP switch, you can make one yourself with some extra wire and a single-pole, double-throw switch. There's a write-up somewhere on this forum on how to do it, you just ground the switch, and then splice the two throws into two wires on the pass. side of the engine bay. If anyone's interested in this, I can take pics later. Just let me know.

if you did a write up or gave me a quick how to, i would do it, cuz i desperately need to keep my car from overheating this summer even at the expense of some mpgs.

thanx

max

[FirebirdGT]

Re: Cooling problem question

Sure, basically there are two wires under the hood on the pass. side. One Pale Green. One Yellow. Run three wires through the grommet in the firewall underneath the PCM. Attach one of thhose wire to a ground, and splice the other two with the two wires I stated before. Attach the ground to the center pole of an SPDT switch, and attach the other wires to the outside. Flip the switch one way, you get one fan, flip it the other, you get both. I'll add a picture tommorrow when it's light enough out.

That is so WRONG!

Green wire grounded is low speed, green AND blue wire is high speed. Both fans always run. You need a DPDT switch.

And if you don't understand wiring diagrams and electric circuits, you shouldn't be messing with electrical mods.

The correct way to wire the 96+ is below:

http://www.firebirdgt.com/fanswitch.htm (mine - extreme advanced version, can be simplified)

http://forum.camarov6.com/showthread.php?t=77114

.

[tkoforpresident]

Re: Cooling problem question

That is so WRONG!

Green wire grounded is low speed, green AND blue wire is high speed. Both fans always run. You need a DPDT switch.

And if you don't understand wiring diagrams and electric circuits, you shouldn't be messing with electrical mods.

The correct way to wire the 96+ is below:

http://www.firebirdgt.com/fanswitch.htm (mine - extreme advanced version, can be simplified)

http://forum.camarov6.com/showthread.php?t=77114

.

hmm, got anything for a 93 ?

[FirebirdGT]

Re: Cooling problem question

hmm, got anything for a 93 ?

Read this:

http://shbox.com/1/4th_gen_tech2.html#cooling

Then this:

http://shbox.com/1/fan_sw_diagram1.jpg


.

[tkoforpresident]

Re: Cooling problem question

Thanks GT.

[Blizzard242]

Re: Cooling problem question

Silly kiddies always having problems with overheating. lmao yeah tko, def don't want to go back into the engine to fix anymore problems eh?