LUVTruck.com

I just got a 81 with the Diesel and am trying to replace the Sensor. The boys at Auto Zone tell me that my truck doesn't have a sensor even though we look at it and see two sensors coming out of the Thermostat housing. What are these? One has one wire and the other has two wires. Since the sensor in the computer they do show for another model is 6 bucks I thought of replacing that first before trying to do the gauge........any suggestions? Any idea what the two wire sensor is?

Bryan

It has been a while since my 81 was diesel powered but I think one of the sensors, the one with the single wire goes to your temp guage. This is easily checked by having someone momentarily ground the wire to the housing while you sit in the seat with the ignition switch on, if the guage needle moves quickly to hot this is the correct temp sensor wire. NAPA still has the correct senders.
The one with two wires goes to the glow plug relay and prevents the glow plugs from functioning when the engine is already at operating temp. because they are not needed then.
Go to the diesel section on this site and ask the same question, I am sure you will get more information, especially from "Joe Isuzu" He is the founder of Isuzu Pup.com and is the foremost expert on Luv diesels. Basically you own a Isuzu Pup, these are all the same from 82-87 so parts for yours are quite available from anywhere Isuzu Pup parts are sold.
Because I live in So CA where everyone is supposed to drive at 75 mph plus I swapped my diesel engine out for a Chevy 350 V8 with a 700R4 automatice to prevent getting ran over!
Good luck, dusty

Thanks - I know what you mean about the freeways.....in PHX we have posted speed at 65 but that only holds true when a policeman is around. When I run at 65 I am getting passed like I'm standing still........... I'll post again on the diesel site and thanks for the help. I did try to ground my wire but had no results so I assume that the gauge is bad but I also read a post where somebody said that he had never heard of a gauge going bad so.........I thought I would go with the easiest to reach and move back from there..........

Bryan

Wow, I composed a reply but it's gone. I'll try again. I always get the two sensors confused, and Dusty seems confident that the 2-wire one goes to the glow system. The other one goes to the fast-idle system. I though it was the opposite, but like I said--I always forget which one is which. Either way, new ones are available, but you'll get sticker shock. They're about $75 each. Or, you can repair those sensors. There are a few posts at IsuzuPup.com with instructions and photos. I've done the one for my glow system, but not the fast-idle.

Neither of these two sensors are anything related to a gauge. The temp gauge sensor is further down on the thermostat housing. It has a little slide-on connector, and it slips onto a contact that's like a nail-head. Once it's on, it swivels freely. That's the one that Dusty says is still available from NAPA.

Jack
P.S.: Dusty is exaggerating my expertise. But I do know who the real experts are.

_________________
'83 Isuzu P'up Diesel LS - Original Owner
JoeIsuzu@IsuzuPup.com
IsuzuPup.com

Jack, there are two identical threads. I suspect you replied to one and not both.