Oil pressure sending unit

[2gen4runner]

I have a 91 4runner v6 and when i bought the truck a year ago, the oil pressure guage never worked. So i unscrewed the sending unit it from the block unclipped it from the wires and grounded it (the wire that goes to the dash) and it worked.
So i assumed the sending unit itself was bad, so i went to a junkyard got a used one and i installed it, and the guage still doesnt work....why???
Could it be a bad unit (rare) or could it be a clog in the block??? This dont make sense!!!:ybrick:

thanks

 

[Saved]

I dounbt it is a clog in the block but stranger things have happened. One way to find out is remove the sending unit and turn the key. If it starts turn it right off and check to see if you have oil all over the place. I would buy a new sending unit from the dealer.

 

[fourwd1]

Make sure you don't have a sending unit for an idiot light connected to a gauge (or vice-versa), they are not compatible.

 

[bigsthedog]

I have a 91 4runner v6 and when i bought the truck a year ago, the oil pressure guage never worked. So i unscrewed the sending unit it from the block unclipped it from the wires and grounded it (the wire that goes to the dash) and it worked.
So i assumed the sending unit itself was bad, so i went to a junkyard got a used one and i installed it, and the guage still doesnt work....why???
Could it be a bad unit (rare) or could it be a clog in the block??? This dont make sense!!!:ybrick:

thanks

I know this post is quite old, but do you have an answer for your problem. I got a 91 v6 3.0 and the same EXACT thing happened.. The gauge works, the wire is good, and i threw a new sender unit on it. Still nothing. I have a feeling my Oil Pump is out even though the truck runs beautifully.