Got a question that I hope I can get an answer to. I just recently replaced the fuel pump on my '03 4Runner V8. The install went fine and the truck is back on the road. Except now my fuel gauge is acting erratic. I filled it up to about half tank and as I was driving I was getting all kinds of screwy readings on the fuel gauge. When I got home after doing a few errands I literally sat in the vehicle and watched the gauge drop to empty and then shoot back up to half full. It’s obvious that I must have screwed up something on the sending unit side, but I am not sure what?? I took great care in handling the fuel pump housing but apparently something happened. So my question is, can the sending unit be bought separately? And is it possible that if I pull the whole assembly out again can I simply fix what I may have inadvertently fouled up? Thanks in advance.

 

Might you have disrupted the wiring in some way? Maybe a bad ground?

 

Most certainly could be,, But i am certain that I will have to drop the tank again. I called Toyota and they do sell the sending unit separately, $89,, eesh, more work ahead