Operating Temperature and Wipers

[Blue02GPGT]

Hello all.

Temp gauge on my 02 Grand Prix 3800 seems wonky. Reads about 85 degrees C at operating temperature. With my cheapy Bluetooth OBD2 reader says the computer is reading 90 degrees at the same time. So the gauge is reading 5 degrees low, but also what the computer is seeing seems low to me as well. 90c? Do these engines generally run that cool?

Also wiper issue. Wiper sweep on the drivers side stops about 6 or 8 inches from the edge of windshield. Also when on delay mode the wipers stop almost full up and stay there. Only on delay, wiper blade park position looks fine when off.

I’m thinking maybe wiper arm to linkage misalignment or linkage to motor misalignment? 

Any ideas? Thanks

Edited April 15, 2022 by Blue02GPGT

[55trucker]

Seeing as you're quoting celsius one can assume you're in Canada?

If the PCM is seeing 90c then one would suspect that the stat is a 92c stat, not necessarily a 95c stat. Don't put your life in the hands of the cluster gauge, They do not read 100% accurate, could very well be the sender.

Wipers?

service manual, service manual, service manual, read the section on diagnostics for the wiper assembly function.

[94 olds vert]

The temp seems normal for one of those cars. The cluster can be off in these cars especially as they age. The Bluetooth reader is more than likely accurate and 5c is close enough to not worry about. 

As for the wipers, remove the cowl and see if there is debris blocking something. Other than that I'm not sure. Might have to dig deeper. 

Best of luck. 

Edited April 16, 2022 by 94 olds vert

[Schurkey]

3 hours ago, Blue02GPGT said:

Hello all.

Temp gauge on my 02 Grand Prix 3800 seems wonky. Reads about 85 degrees C at operating temperature. With my cheapy Bluetooth OBD2 reader says the computer is reading 90 degrees at the same time. So the gauge is reading 5 degrees low, but also what the computer is seeing seems low to me as well. 90c? Do these engines generally run that cool?

90 C = 194 in real degrees.

I wouldn't expect the fan to come on until ~220.  So I'd expect to see the gauge go higher than "85" in the summer, on longer drives.

3 hours ago, Blue02GPGT said:

Also wiper issue. Wiper sweep on the drivers side stops about 6 or 8 inches from the edge of windshield. Also when on delay mode the wipers stop almost full up and stay there. Only on delay, wiper blade park position looks fine when off.

I’m thinking maybe wiper arm to linkage misalignment or linkage to motor misalignment? 

Any ideas? Thanks

I don't know about '02.  On my '92, there's some--but not much--potential movement (adjustment) between the wiper arm and the splined shaft that moves it.  You might try removing the arm, to see if it can be relocated on the splines so that the sweep goes farther over.  Verify that the wiper transmission joints aren't worn-out.

As for the wipers staying "up" on delay--I would suspect problems with the electronic circuit board.  On earlier GM vehicles, there were known problems with broken solder joints on the wiper board.  Re-flowing the solder was the usual "fix", and the re-solder could last for years.  But again--I don't know about '02.

Edited April 16, 2022 by Schurkey

[Blue02GPGT]

Thanks for the thoughts and ideas fellas .
 

Yes I’m a Canadian boy, complete with metric system.

So on the Temp issue, my concern is mostly for the idiot light. In the event of an overheat, if it’s reading low I would think that would cause a delay in the temperature warning light to come on. It’s the girlfriends DD...

I have replace the coolant temp sender, as it was externally corroded and not expensive. 

I suppose if I get my hands on a laser temp reader gun I’ll compare the gauge and pcm readings to the actual temperature at the temp sender.

On the wipers I’ll have to start taking things apart. Thanks Schurkey for the info on the circuit board, I’ll look into that.

[Schurkey]

I'd trust the sensor for the ECM before I'd trust an infra-red "temp gun".

The "dirty little secret" in the "infra-red temp gun" industry is "Emissivity".  Different materials emit different amounts of infra-red; the "gun" has to be calibrated for the material you're taking the temperature of...and most guns aren't adjustable.   Even with an adjustable gun, you have to know the material's temperature so you can calibrate the gun; so you can't find out the temperature until you already know the temperature.

Short story:  Infra-red temp guns can be wildly inaccurate, depending on what you're pointing them at.