The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > General Truck Forums > Electrical

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 11-17-2014, 12:27 PM   #1
aggie91
I'm just glad to be here!
 
aggie91's Avatar
 
Join Date: Jan 2008
Location: Longview, TX
Posts: 4,788
Question Oil and Temp sensor wiring ??'s

Here is my issue that I need some help on.

I am putting a 1990 Suburban cluster in my 1985 truck while doing the LS swap. I have most of the wiring figured out, but have a couple of questions I need to get clarified.

I bought the sensors/senders for the oil pressure and water temperature for a 1990 suburban. First Question: Did I really need to do that? Or would the senders from the 1985 work with the gauges in the 1990 cluster? I ask that because the 1990 sensors are multi wire plugs on both where as the 1985 ones are single wire for the gauges (the oil pressure does have multip[le wires for the ECM in the 1985, but all that is going away...)

Second Question: If I do need the 1990 sensors, do I just run the single wire for the correct pin on the connector for the sensor? The wire schematic shows (for a 1990 suburban) shows a single tan wire to the center terminal and the connector I pulled from the wrecking yard has a tan wire on the center terminal, the other two wires being orange and gray.

Third Question: The 1990 temp sensor has 2 wires, the generic connector that came with the new sensor has both wires being black. The schematic show the harnes wire as a dark green. Which pin on the connector do I use? What is the other wire for?

Thanks in advance for any help...
__________________
Karl



1965 Chevy Stepside(Grandpa's Old Blue) and (July 2015 Shop Build!)(2020, the Saga Continues)
http://67-72chevytrucks.com/vboard/s...d.php?t=372424

The LST Challenge:
http://67-72chevytrucks.com/vboard/s...=1#post7812257

Korbin's 1st Square: "Sunburn"
http://67-72chevytrucks.com/vboard/s...d.php?t=418618

1985 GMC Sierra: "White Trash", Korbin's 2nd now...
http://67-72chevytrucks.com/vboard/s...d.php?t=632305

Henry - 1984 Chevrolet, Owen's 1st Square
aggie91 is offline   Reply With Quote
Old 11-18-2014, 03:33 PM   #2
aggie91
I'm just glad to be here!
 
aggie91's Avatar
 
Join Date: Jan 2008
Location: Longview, TX
Posts: 4,788
Re: Oil and Temp sensor wiring ??'s

I did some more research last night. I figiured out the Oil Pressure sender. I will be using the 1990 sender. I only need to run the tan wire to the center pin. The other 2 are for the fuel pump circuit which I am not going to use.

now I just need to figure out the temp sensor wiring...
__________________
Karl



1965 Chevy Stepside(Grandpa's Old Blue) and (July 2015 Shop Build!)(2020, the Saga Continues)
http://67-72chevytrucks.com/vboard/s...d.php?t=372424

The LST Challenge:
http://67-72chevytrucks.com/vboard/s...=1#post7812257

Korbin's 1st Square: "Sunburn"
http://67-72chevytrucks.com/vboard/s...d.php?t=418618

1985 GMC Sierra: "White Trash", Korbin's 2nd now...
http://67-72chevytrucks.com/vboard/s...d.php?t=632305

Henry - 1984 Chevrolet, Owen's 1st Square
aggie91 is offline   Reply With Quote
Old 11-18-2014, 09:21 PM   #3
88Ironduke
Registered User
 
Join Date: Jul 2010
Location: Willingboro, NJ
Posts: 489
Re: Oil and Temp sensor wiring ??'s

Just a thought from the outside view on your fuel pump circuit. The fuel pump relays in late model GMs were primarily operated by the ECM/PCM. The engineers also added a circuit to operate the fuel pump relay ECM via the oil pressure sending unit in the event of a internal driver failure onboard the ECM/PCM. Misconception that it is a safety device that cuts off at low oil pressure so you don't grenade an engine. Its nothing more than a back up circuit to ensure the fuel pump relay always works.

88Ironduke
__________________
Retired USAF - No rockets, no mortars, no bad guys shooting...No stress!!!

My Build Thread: Project 72' Green
http://67-72chevytrucks.com/vboard/s...d.php?t=587932
88Ironduke is offline   Reply With Quote
Old 11-19-2014, 10:30 AM   #4
aggie91
I'm just glad to be here!
 
aggie91's Avatar
 
Join Date: Jan 2008
Location: Longview, TX
Posts: 4,788
Re: Oil and Temp sensor wiring ??'s

Thanks for the input 88Ironduke.

I figured out the temp sensor wiring issue that I was thinking thru. After further investigation of the 1990 vehicle wiring diagrams (found on this site BTW), I did some parts searching. Turns out that GM put temp sensors/senders in the engine for a few years. The one that I first purchased was the one wired with a yellow and black wire in a 2 pole connector. Those wires go to the ECM on the 1990 engine. There is another temp sensor for the gauges, it is hooked up with a single dark green wire.

So a bit of searching on Rock Auto, turns up the part number for the sensor I need, TU66. So off to Auto Zone I go last night to return the one I do not need and get this one. they had it in stock and it was $3 less than the one I returned..

So, looks like I have all the items I need to complete my LS swap with the 1990 instrument cluster in my 1985 GMC C15.
__________________
Karl



1965 Chevy Stepside(Grandpa's Old Blue) and (July 2015 Shop Build!)(2020, the Saga Continues)
http://67-72chevytrucks.com/vboard/s...d.php?t=372424

The LST Challenge:
http://67-72chevytrucks.com/vboard/s...=1#post7812257

Korbin's 1st Square: "Sunburn"
http://67-72chevytrucks.com/vboard/s...d.php?t=418618

1985 GMC Sierra: "White Trash", Korbin's 2nd now...
http://67-72chevytrucks.com/vboard/s...d.php?t=632305

Henry - 1984 Chevrolet, Owen's 1st Square
aggie91 is offline   Reply With Quote
Reply

Bookmarks

Tags
1990 cluster, gauges, senders, sensors

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 02:05 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com