90 4runner throwing code 22 - Water temp sensor

'90 4runner w/ the V6

I'm trying to help a friend find out the problem with his rig.

From my understanding, the truck will run fine sometimes, and other times it will run rough and miss to where you can't drive it. It will also start running bad in the middle of driving, even if it was running good. When it does run bad, it doesn't get better and you have to shut off the truck. But then if you go back in a little bit, the truck may run just fine.

First things first, I told him we would check his computer. The only code it threw was CODE 22-Water Temp. Sensor Signal(open or short circuit in water temp. sensor signal(THW)).

Well, my question is would this be causing an engine problem like this?

I'm going to reset his computer and see if the same code pops up. Until then, I don't know what do think.

Thanks for any info.