I know there has been a post on this, But , I just bought a 1988 pickup 4x4 and I have been having problems getting the temp and fuel gauge to work right, My model # on truck is VZN66L-MDCEA which I am sure its a deluxe model , well it has a tech and im sure its a SR5 model instrument cluster. how can I tell what it should have, when you turn on key ( not starting ) the temp needle will rise to the 1\4 mark and stay there ( even if I unplug the wire to the sending unit and the fuel gauge will rise and not go down after key is switched off, but temp will when key is off. I think someone put an SR5 gauges in it. So how do I tell what really belongs in it, last owner did have an aftermarket temp gauge under dash.

 

Well I finely found a new temp gauge for my truck and it worked great for about 2 weeks, now its doing the same thing again. I start it cold and a min or two later it going half way on the gauge. any idea's on how to fix ?

 

I would make sure all of the wires going from the sender to the gauge are intact and all of the connections are clean and tight. If the wires check out fine, then you can try this fix to a seemingly very common problem:


https://www.yotatech.com/forums/f116...ge-fix-271152/

 

There is a Toyota site that you can put your VIN and see what is on your truck but don't remember the site. Is your truck a base model truck? If very few options I would say it came with no SR5 gauge.

Temp gauge is not the best on these trucks.

The fuel gauge is most likely the sending unit in the tank. The wiper on the resistance in the tank tends to rub the hair like wire in two.