: Another Temp thread...



only_1
09-20-04, 04:35 PM
I have a 96 eldo with temp issues.
I'll start by saying that before the car even starts the temp gage reads one and a half marks above cold. This is in 65-70 degree weather.
My car runs warm according to this gage. What I have done is: flush the cooling system twice, replace the temp sender, have the radiator rodded, new thermostat, fresh dexcool/water, new waterpump belt, greased the tensioner even though it really didn't need it. I drive the car alot so I don't mind putting new parts on it since most have 138K miles.
Any ideas are greatly appreciated. Do the gages wear out, do waterpumps often go out? The waterpump spins fine and all the veins look like they are in good shape.

oldgamer
09-20-04, 06:05 PM
Sory, you changed a lot of parts too early I guess.
If temp gage reads wrong even before you start engine, how this can be related to bad termostat or let say, water belt?
1. Does the engine get overheated acordingly the temp gage after you drive for some time?
2. Does the engine get overheated in reality?

In any cases, if engine is cold and the gage reads realy high temperature it's looks for me like sensor or wiring problem. You changed the sensor already, so it possible the wiring problem.

only_1
09-20-04, 06:25 PM
The wiring looked good and wasn't brittle. I know that doesn't mean much. I know its not the head gasket, I pressure tested it right away. What point on the gauge do the fans kick on? On my car it is the last mark before it hits the red area. It is supposed to be 229 degrees. At 170 degrees I am past the center mark. I used a digital temp gun.

oldgamer
09-20-04, 06:31 PM
Again, like I understood, the temp gauge reads hot engine even if the engine is cold, right? There is nothing to do with head gasket.
You didn't answer for questions I asked, if the engine REALY gets overheated or just temp gage just reads that. Sorry, I don't follow.

only_1
09-20-04, 06:52 PM
I will try to be very clear then.
1. Yes the engine runs warm according to the gauge after driven for a while. It seems to cool off when I get out of traffic and can stay in the rpm.
2. I do not know in reality what the temperature is when the gauge is at one mark before the red area. I do not know what the temperature is supposed to be when the gauge is straight up in the center position either, but I do know that it is actually less than 170 degrees.
I am going to recheck my wiring with a multimeter. Is there any way to recalibrate the gauge cluster?

oldgamer
09-20-04, 07:00 PM
1.If engine gets worm (not too hot) after driven for a while I consider this is a normal.

Does engine switch to limp mode? Did you get any warning messages?

only_1
09-20-04, 07:35 PM
No, I get no warning messages. I have only noticed the fans kick on a couple of times since I have owned the car (except when running AC).
I am very meticulous about the things I own, and the gauge not reading correctly must be fixxed.

peteski
09-21-04, 12:31 AM
Why not just verify the temperature sensor circuit first?

I don't have the specific details handy, but you should enter the diagnostic mode and display the Engine Temperature parameter while in the PCM Data Mode.

Do this with the engine cold and not running. Touch the engine first to make sure that it really is cold (close to ambient temperature). That parameter should then display temperature close to ambient. You can tell the ambient temperature from your climate control display (assuming that it works properly) :)

If you see the Engine Temperature parameter is reading much higher than ambient temp, then your engine is not really running too hot - just the sensing circuitry is reporting it to be too hot.

If you;ve already replaced the temperature sensor then the wiring or the PCM computer could be faulty. Are you sure you replaced the correct sensor? Northstar has several temperature sensors.

Peteski

only_1
09-21-04, 02:46 PM
I replaced the temp sensor on the right rear cylinder head. The one that tells the pcm the temp code, verified by the yellow and black wires. I have been told that there was just one ect sensor on the 96 northstar.

oldgamer
09-21-04, 04:23 PM
Before changing the sensor, you better check the data PCM gets, like peteski told you. Otherwhize, you will just waste, and waste, and waste...

only_1
09-21-04, 04:55 PM
How do you access the PCM data? Is it under IPC data? All I get under PCM is codes, and clear codes. There is no option for data like there is for the other systems.

oldgamer
09-22-04, 04:25 PM
When you access to codes, you'll get all codes in history at first, then computer will ask you "PCM?". You should press "HI". Then computer will ask "PCM DATA?". You should press "HI" again. Then computer will show you data PD01. You need to read data for PD04. Press "HI" untill you get PD04.

zonie77
09-23-04, 03:21 PM
Going to your initial post:

Does the gauge show that before you insert the key? If so it's meaningless. It's about where the gauge was when you shut it off. The gauge can move slightly when it's off but it usually stays somewhere in the middle.