Temp gauge problem
Thread Starter
|
More Turbo
Joined: Nov 2006
Posts: 538
Likes: 11
From: Great N/W
Temp gauge problem
1995 f-250 4x4 standard cab 460 auto. My temp gauge is pegged. I replaced the sending unit (NAPA) and have the same issue. If I unplug the sending unit it the needle drops a little, but not much. Attaching the sending unit only pegs the gauge again. After running for 15-20 minutes it'll drop to the O in normal, bounce rapidly a couple needle widths, then peg again. It'll cycle itself like this over time. All other gauges read normally, engine temps are normal, and no CEL.
Any ideas ? Anyone experience this problem before ? Thanks for any help !!!
Any ideas ? Anyone experience this problem before ? Thanks for any help !!!
Cargo Master
Joined: Apr 2003
Posts: 3,476
Likes: 224
From: Frequently frozen MN
Your temp sensor is a resistor that changes with the temp. Resistance should be lower as the temp goes up.
This makes me think that you have a partial short somewhere in the connection from your gauge to the sensor.
When you hook your sensor, it adds resistance in parallel, which lowers the overall resistance further. (This is just part of my reasoning. Not important if you know what I mean ). This causes the gauge to read hotter.
Anyway, check your wiring and panel. I would get an ohmeter and check the resistance of the sensor wire to ground. Then I'd see if there were any connections along the way to help isolate the problem. (If you can disconnect the wire at any point, you could see which side has the partial short).
Oh, and pull the positive batt wire off while you're checking things. There are reasons why it could cause confusing readings.
Good Luck,
hj
This makes me think that you have a partial short somewhere in the connection from your gauge to the sensor.
When you hook your sensor, it adds resistance in parallel, which lowers the overall resistance further. (This is just part of my reasoning. Not important if you know what I mean ). This causes the gauge to read hotter.
Anyway, check your wiring and panel. I would get an ohmeter and check the resistance of the sensor wire to ground. Then I'd see if there were any connections along the way to help isolate the problem. (If you can disconnect the wire at any point, you could see which side has the partial short).
Oh, and pull the positive batt wire off while you're checking things. There are reasons why it could cause confusing readings.
Good Luck,
hj
Fleet Owner
Joined: Aug 2005
Posts: 23,666
Likes: 301
From: Easton,Ks
Replace the Temp sender.
Another poster just had the same problem when replacing the sender with one from NAPA.
They must have a bad run of senders.
Also make sure you are changing the right item. The one you want to change only has one wire to it and it pushes onto the sender. It sets behind the distributor and screws into the intake manifold itself.
Another poster just had the same problem when replacing the sender with one from NAPA.
They must have a bad run of senders.
Also make sure you are changing the right item. The one you want to change only has one wire to it and it pushes onto the sender. It sets behind the distributor and screws into the intake manifold itself.
Thread
Thread Starter
Forum
Replies
Last Post
GoldCo
1948 - 1956 F1, F100 & Larger F-Series Trucks
5
Jul 24, 2017 01:53 PM
helomech
Explorer, Sport Trac, Mountaineer & Aviator
12
Dec 17, 2016 09:43 PM
st8yd
1999 - 2003 7.3L Power Stroke Diesel
17
Nov 30, 2015 07:23 PM
