Youngs92

iTrader: (1)

I'm replacing my EGR and just found a single wire that comes off a sensor on the EGR valve. Where is this supposed to go and would it be bad to not have it connected?

paulo57509

That sensor is there to tell the ECM that the EGR is open. If the sensor isn't connected, the ECM thinks the EGR isn't opening when it demands EGR. The ECM will then turn on the CEL and set a trouble code.

There should be a mating connector someplace towards the distributor - I think...I can't recall its exact location (CRS disease).

Youngs92

iTrader: (1)

Interesting. Im fairly certain this hasn't been connected for a while but I haven't gotten any codes. Does the mating connector come from the big connector on the driver side firewall? Any idea what color the wire should be?

TylerSteez

iTrader: (3)

Yep it's the egr temp switch and the guy above explained it good, the connector that it plugs into will be hidden around the distributor area right next to the egr solenoid, I can't remember the color of the wire running to it but it's either black or possibly orange(I have a very small small feeling there's something orange about it). Just take a good hard look around the distributor and you'll find it. I recently put a new temp switch in my car after I was getting code 32 and it got rid of the code immediately.

Youngs92

iTrader: (1)

Thanks guys. According to the diagram (link below) the only thing I see linked to the EGR is the solenoid and it has a grey wire. I'm pretty sure that's not what I'm looking for though. If anyone can pass along a TPI ECM wiring diagram that shows this that would be awesome. Was this only available on all vin F TPIs?

Youngs92

iTrader: (1)

Forgot the link

http://austinthirdgen.org/mkportal/modules/contents/images/Fig36_1988_5_0L_Tuned_Port_Injection_engine_wiring.gif

TylerSteez

iTrader: (3)

Went out and snapped a pic for you of the connector attached to the temp switch, if you look carefully the wire comes out from under the wiring harness and straight up into my hand,

TylerSteez

iTrader: (3)

It lives right in there

Youngs92

iTrader: (1)

Thanks for the pictures. I figured it should come out somewhere around there, but I can't for the life of me find it. I plan to run a new wire from the ECM tonight. Can you tell me what color the wire going back to the ECM is? The wiring diagrams suggest it's green

ASE doc

The 92 uses fuel trims to detect EGR operation. The temp sensor serves no purpose in that design. GM went away from the temp sensor because of so much trouble with false setting of code 32.

The code would set on hot restarts because the sensor was hot from manifold heat soak so the ECM thought the EGR was open when not commanded.