temp gauge pegged

**PatriotGT** · 08-20-2010

Car can sit for 18 hours, gauge sitting at rest (100) within 5 min
it's in the red. You can touch the rad hoses and they
are still cold to the touch, but I changed out the temp sensor (3x),
rad (around a year ago) dropped t-stat to a lower temp and the problem
has gotten progressivly worst. I use a infrared temp gun on it the other
day and the highest it got was 180 (on hoses, t-stat housing, sending
unit and radiator). Water pump is working, suspecting the gauge,
but maybe the pcm. How hard is it to change out the gauge and is there
anyway to check it. Is the pcm the same thing as an ecu?
Thanks, Larry

Mods: if posted in the wrong place lmk and please move it.

just got back from having temp read on computer, showing 191 while the
interior gauge is reading 80 more.

**QUICKSILVER462** · 08-20-2010

Have you check the engine coolant sensor, it is located in the intake manifold under the thermostat. You can chack the resistance with an ohm meter, and then compare that with the specs of the part (sorry I don't know what the readings should be), but this will tell you is you have a faulty sensor or not.

**PatriotGT** · 08-20-2010

That's the one I was calling the temp sensor.
Have changed it out 3x's after reading about others getting a bad one.
First 2 came from AZ and the last from Oreillys.
Tried using ohm meter while still on the car and it went from nothing to
almost infinite as the engine heated. I may change it out once again
with one form a dealer. Crazy thing is, the computer is getting the correct
readings.
The shop I took it to today suggested another gauge. Opinion?

**PatriotGT** · 08-22-2010

Anyone know if there's a place to hook up an
aftermarket temp gauge? (3.8)
Thanks, Larry

**matt5112** · 08-22-2010

did you at least get the dealer temp sender?

**PatriotGT** · 08-23-2010

Not yet. My wife just took it to a local dealer today,
They too are thinking gauge.
Now to figure out to R&R it.

**PatriotGT** · 08-28-2010

Just thpught I'd update. Changed out gauge, but still had the same
problem, so we (my son and I) replaced the original. Went to dealer
this morning and got another sensor, seems to be working now.
Now I've gotten another problem, got to change out the plenum
gasket, it's leaking right behind the alternator.
Anyone know if this is a hard job? Dealer wants $382.

**TheOtherNick** · 08-28-2010

not hard at all. ALLDATAdiy.com :: Leading Source of Diagnostic and Repair Information buy a subscription to your car and it will tell you basicly how to do everything.

**TheOtherNick** · 08-28-2010

also get a new plenum. Factory ones melt around the egr tube.

**PatriotGT** · 08-29-2010

^^ thanks, the dealer kinda' implied the same thing.

It was also suggested to check out where the heater hose
connects to the manifold, to the right and below the alternator,
that it may be the cause of the leak and from what I can see, the
leak looks very close to that point. Any input on that?