Which ECM temperature sensor is correct for the 2.5? Different ones listed (Page 1/2)
cebix NOV 13, 02:59 AM
My ECM temperature sensor is reading cold. I want to replace it but wondering which one is the correct one. I read that some have smaller threads and need adapter bushings to screw into the thermostat housing. Which of these do I need? I've got an 85 duke auto w/AC.

AC Delco 2134396 vs 1551107 - these are for sale at rockauto and not sure of the differences. Many thanks.
fierofool NOV 13, 07:02 AM
AutoZone lists the following. No adapter is required. The V6 has a reducer/adapter that screws into the end of the lower intake and the ECM temp sensor screws into that reducer, but not for the Duke.


IT FITS. This product is a fit for your: 1985 Pontiac Fiero 2.5L TBI OHV 4cyl
Part Number: SU109
Alternate Part Number: PT3378
Warranty: Limited Lifetime
cebix NOV 13, 08:09 AM
Thanks, but for shipping cost purposes I can only do rockauto on this one and they don't carry the number you gave. Does a Delphi TS10075 sound good too?

[This message has been edited by cebix (edited 11-13-2019).]

fierofool NOV 13, 08:30 AM
Looking at the Rock Auto site, that is a unit that should work. Direct fit. No adapter. No harness splicing required. Any of the sensors on that page that have an oval head on them will work.
cebix NOV 13, 09:01 AM
Cool, thanks. Last question - any brand preferred amongst you guys? Is Delphi good or should I go Delco?
Gall757 NOV 13, 09:35 AM

quote
Originally posted by cebix:
Is Delphi good or should I go Delco?



likely they both come out of the same Chinese factory.....
cebix NOV 13, 10:13 AM
Guess there are no known quality alternatives?
theogre NOV 13, 10:58 AM
New ECM sensor needs New Plug.
You must install a new plug if you have OE sensor and plug.
Plug should be Soldered to old wiring or likely will have problems down the road.
(87 and up have the new type as OE and shouldn't need new plug unless damage.)

------------------
Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave

cebix NOV 14, 12:10 PM
There seems to be a problem with buying and shipping a new plug. Can anyone tell me from these photos do I have the new plug already or is it still OEM?

The only alternative I have is buying an NTK sensor which comes with the plug and wiring. All other sensors come just by themselves.



[This message has been edited by cebix (edited 11-14-2019).]

Patrick NOV 14, 03:18 PM

quote
Originally posted by cebix:

My ECM temperature sensor is reading cold.



I'm just curious... how are you establishing that?