LT1 Based Engine Tech 1993-1997 LT1/LT4 Engine Related

Temp Sensor problems

Thread Tools
 
Search this Thread
 
Old Apr 11, 2009 | 01:35 PM
  #1  
Amped96's Avatar
Thread Starter
Registered User
 
Joined: May 2000
Posts: 249
From: Memphis, TN
Temp Sensor problems

I noticed on my scanmaster that the coolant temp was always reading -40*. I also am having warm start problems (car starts perfectly when cold). I replaced the sensor in the waterpump and the scanmaster still shows -40*. What should I check next??
Old Apr 11, 2009 | 03:41 PM
  #2  
Injuneer's Avatar
Administrator
 
Joined: Nov 1998
Posts: 71,094
From: Hell was full so they sent me to NJ
Pull the harness connector off the sensor, and verify that you have 5V across the two sensor pins with the key on.

Did you get the correct 2-pin sensor? Did you check the coolant sensor before you replaced it, using Shoebox's guidelines?

http://shbox.com/1/4th_gen_tech2.html#ect
Old Apr 11, 2009 | 08:29 PM
  #3  
Amped96's Avatar
Thread Starter
Registered User
 
Joined: May 2000
Posts: 249
From: Memphis, TN
Thanks for the link. After all these years, I still don't put shoebox's page to full use like I should.

I checked the harness and was getting intermittent 5v DC. To confirm this, I plugged the harness into the new sensor which is in the car and I had my GF watch the scanmaster while I wiggled the wire and it would jump from 82 to -40* as I wiggled the wires. I then plugged it into the old sensor which is out of the car and got 76* to -40, so I guess my old sensor was fine.

I guess I have a bad connection in the harness. The wires just behind the connector look to be in bad shape (can see some bare wire through some holes in the yellow covering).

What are my options when the problem is the harness? Is there a place I can get a new connector? What I am thinking is to cut the wires and put a new connector on the shorter wires. Am I way off here or could it be that simple?
Old Apr 11, 2009 | 08:40 PM
  #4  
Amped96's Avatar
Thread Starter
Registered User
 
Joined: May 2000
Posts: 249
From: Memphis, TN
I found this on autozone's page. Anyone had any luck with these?

http://www.autozone.com/autozone/cat...012&questions=[]
Old Apr 12, 2009 | 08:22 AM
  #5  
Injuneer's Avatar
Administrator
 
Joined: Nov 1998
Posts: 71,094
From: Hell was full so they sent me to NJ
Originally Posted by Amped96
Thanks for the link. After all these years, I still don't put shoebox's page to full use like I should.

I checked the harness and was getting intermittent 5v DC. To confirm this, I plugged the harness into the new sensor which is in the car and I had my GF watch the scanmaster while I wiggled the wire and it would jump from 82 to -40* as I wiggled the wires. I then plugged it into the old sensor which is out of the car and got 76* to -40, so I guess my old sensor was fine.

I guess I have a bad connection in the harness. The wires just behind the connector look to be in bad shape (can see some bare wire through some holes in the yellow covering).

What are my options when the problem is the harness? Is there a place I can get a new connector? What I am thinking is to cut the wires and put a new connector on the shorter wires. Am I way off here or could it be that simple?
As you discovered, replacement connector with a short length of wire, is called a pigtail. Did you try Shoebox ? Pigtail part #'s are on the right side of the page, at the top:

http://shbox.com/1/Parts.htm

You have to make sure you remove the faulty part of the old harness wiring. Then its "simple".

Last edited by Injuneer; Apr 12, 2009 at 11:36 PM.
Old Apr 12, 2009 | 01:57 PM
  #6  
Amped96's Avatar
Thread Starter
Registered User
 
Joined: May 2000
Posts: 249
From: Memphis, TN
I have looked at that page countless times and never paid attention to the right side...hah.

I went ahead and went to AZ and got their pigtail. The employees at the first AZ I went to acted confused by the part number '254'. The computer said it was in stock, but they couldn't find it. They called another AZ about 15 minutes away and confirmed they had it. I drove to the other AZ and picked it up and they gave me 10% off for my troubles.

I cut off the bad wiring and the old connector and soldered on the new pigtail and its working like a champ. Warm starts are no longer a problem and my dash looks naked without that SES light.

Thanks for the help!
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
HectorM52
Parts For Sale
26
Jul 30, 2017 11:46 AM
Magenta_Hearts
LT1 Based Engine Tech
15
Mar 29, 2017 08:54 PM
AlaskaZ28
LT1 Based Engine Tech
9
Jan 1, 2015 12:30 PM
AlaskaZ28
New Member Introduction
2
Dec 10, 2014 02:39 PM
AlaskaZ28
LT1 Based Engine Tech
1
Dec 10, 2014 02:37 PM




All times are GMT -5. The time now is 05:05 PM.