radiator fans

sssrrrrrr · #1 12-04-2005, 06:01 PM

I read all the threads but didnt see any on this problem so here goes...
I had issues with the overflow bottle- thats how this all started. Replaced it because the cap threads and bottle threads were screwed. Then it kept over heating and I noticed that the new overflow was peachy but the fans werent kicking on. So I convinced myself to replace the thermostat and coolant temperature sensor. (which was a total pain in the ass) and yet the fans still werent coming on. I went to Pep Boys today and tried 3 diff relays- the owners manual showed one for "cooling fan", one for "cooling fan #1", and one for "cooling fan #2". None of them made the fans come on. In addition to that there is a fuse listed but it looked ok...
Any thoughts on this would make me ecstatic at this point. Thanks!

MT-2500 · #2 12-04-2005, 06:38 PM

Year and eng would have helped.
But you realy need to get it on a engine capable scanner and check the cooling fan system.
A lot of good info and test on a good scanner.
It should point you right to the problem.
Has it been showing any check engine lights?
MT

sssrrrrrr · #3 12-04-2005, 08:37 PM

no engine lights come on. 2000 3.4 ltr. i dont have a scanner or the money for one they wanted 85 dollars just to run diagnostics on it

BNaylor · #4 12-05-2005, 10:06 AM

Out of curiousity is the car overheating? What is the temperature gauge reading? Normally, the fans do not turn on until the engine reaches over 220 degrees in normal driving conditions. The powertrain control control module (PCM) through output module drivers is what turns the fans on/off by controlling the cooling fan relays. It references to the engine coolant temperature sensor (ECT) to monitor engine temperature by sending a 5v reference signal to the ECT which is a thermal resistor that varies resistance and then sends the varying signal back to the PCM to determine whether fans should be turned on.

Also, the ECT gives the reading on the temperature gauge.

sssrrrrrr · #5 12-06-2005, 01:15 AM

nope- at this point the car isnt overheating. if im in traffic or something it may get close to the half way mark- i thing it has a little to do with the cool temperatures of 30-50 degrees. if im moving at a steady pace it definately stays half way between the quarter and half marks. when i was trying the relays i would rev the engine till it got over the halfway mark but they didnt turn on. Also the thermostat i installed was a 180 degree one not the 195...

JTrujillo86 · #6 12-06-2005, 03:03 AM

That's probably your issue. The car isn't getting hot enough, especially driving in 30 degree temps. Plus that 180 degree thermostat isn't helping the issue. I would change it if I were because it's not good if the car never fully warms up. Using a 180 thermostat won't let the car fully warm up.

- Jeremy

sssrrrrrr · #7 12-06-2005, 09:14 AM

Thank you. Its worth a try. I went for the 180 because ive seen alot about it being better to run ur car cooler for performance and thats the direction i want to go with this car. Ive thought about breaking down and getting somethin like the scanner on pfyc

http://www.pfyc.com/store/merchant.m...y_Code=ALOTHER

BNaylor · #8 12-06-2005, 09:26 AM

I agree with Jeremy that the 180 degree thermostat is one reason why the fans are not turning on but I really don't think you have a problem. Even with a 195 degree there is a high probability the fans won't turn on if it is cold out. Although GM designed the car to run with the 195 TS the turn on point is 220 and above degrees engine temperature. Your temperature reading are no wheres near that so the PCM doesn't see any reason to turn the fans on.

BTW - We have a 180 degree thermostat along with a few mods. It works fine in our situation but it will depend on where you live and what time of year it is. BTW - The thermostat is a PITA to install compared to other cars.

BNaylor · #9 12-06-2005, 10:18 AM

Quote:

Originally Posted by sssrrrrrr

thats the direction i want to go with this car. Ive thought about breaking down and getting somethin like the scanner on pfyc

http://www.pfyc.com/store/merchant.m...y_Code=ALOTHER

Autotap is a good program. I use it to tune my GTP. Just be sure you have a laptop which decent CPU speed to run it. Got it off of Ebay and the price was better than PFYC.

To date we have a Magnaflow Hi-Flow CAT, CAI, and RSM Racing throttle body. Looking into getting a DHP custom programmed PCM because they program the fan turn on point for 185 degrees so you can supposedly run a 180 degree thermostat with no problems throughout the year.

sssrrrrrr · #10 12-07-2005, 12:01 AM

Thanks so much for the input guys! I will just keep an eye on it then and will let you know if anything ever does happen- maybe im just used to stuff going wrong with it ; ) I agree with the PITA part on the thermostat. There was hardly any space to work with and didnt wanna take anything else off. And that is why Im in no hurry to slap a 195 back on. I live in Dallas which gets pretty miserable in summer so ill see how it does then anyway.... Oh and thanks for the input on the auto tap ill go on ebay an look for it! Much appreciated.

sssrrrrrr · #11 12-07-2005, 12:14 AM

Hey whered u get the cat exhaust? And where can u find a PCM?
LOL so far the only "mod" i have is like a stage 1 intake... i want the stage 3 on pfyc- but which is better the stage 3 or the cold air box one?

BNaylor · #12 12-07-2005, 08:16 AM

Quote:

Originally Posted by sssrrrrrr

Hey whered u get the cat exhaust? And where can u find a PCM?
LOL so far the only "mod" i have is like a stage 1 intake... i want the stage 3 on pfyc- but which is better the stage 3 or the cold air box one?

We got the Magnaflow Hi-Flow CAT from a local muffler shop. Part & labor was around $150. The Digital Horsepower PCM is available on PFYC for $215.

We have the equivalent of a Stage 1 CAI but with a RSM Racing 62mm throttle body. It is surprising how well the 3.4 takes to bolt-on mods.

sssrrrrrr · #13 12-07-2005, 10:29 AM

Nice Thanks alot man.

tribal terror · #14 01-05-2006, 11:05 AM

You guys kill me. You don't have the money to get it fixed properly but you waste all kinds of dough on guessing because someones fathers, sons, girlfriends car did it 20 years ago.If you find a good honest mechanic you don't get taken and what seems like alot for a scan, in all reality isn't a fraction of what you waste guessing. The scan tools doesn't fix the car, it's the user that has to know what he is doing with the scan tool.Do a search and see how many people replace things because that was the code and it doesn't fix it.Not trying to be a prick but I make a living scanning cars and get paid for the diagnostics so I really don't care if you changed the part yourself.All mechanics are not crooks.The price of training and tools doesn't come close to the $ I charge for scans.

sssrrrrrr · #15 01-05-2006, 11:29 AM

Quote:

Originally Posted by tribal terror

You guys kill me. You don't have the money to get it fixed properly but you waste all kinds of dough on guessing because someones fathers, sons, girlfriends car did it 20 years ago.If you find a good honest mechanic you don't get taken and what seems like alot for a scan, in all reality isn't a fraction of what you waste guessing. The scan tools doesn't fix the car, it's the user that has to know what he is doing with the scan tool.Do a search and see how many people replace things because that was the code and it doesn't fix it.Not trying to be a prick but I make a living scanning cars and get paid for the diagnostics so I really don't care if you changed the part yourself.All mechanics are not crooks.The price of training and tools doesn't come close to the $ I charge for scans.

i never said mechanics were crooks. I only said i couldnt aford it. i havent wasted money. all i spent was the 6 dollars for a thermostat. find somethin else to rage about.

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