i have a 94 2wd 5.0 that runs ok on the front tank and has an occasion mis fire on the front tank, but when on the highway it runs fine. however when on the rear tank it just dosnt keep up, the check engine light comes on and goes off periodically, and from a stop its just lags out and trys to shift but wont, its all kinds of odd things going on....any help??? thanks!

 

im betting your sending unit is shot, or wiring to the unit is shot. not a mechanical genius, but the connections would be the first things i would check... oh and welcome to the site!

 

Would i have to drop the tank for that? And thanks!

 

Also why would it matter if the sending unit is junk? Dosent that just tell the fuel gauge the tank level? Im not sure myself..

 

If it has fuel pumps in each tank, maybe the rear tank fuel pump is going out.

 

That was my 1st thought too. But it dosnt ever die or miss on the rear tank. Just is sluggish from a stop...and the trans shifts slower or has a delay..it almost seems like its trying to shift up and downthe the same time...if im going 45+ mph on the front tank and switch tanks it'll be fine for about 10 or 15 miles then it becomes sluggish and the trans issue comes back..and the check engine light comes on..if i keep driving for. About 10 miles the light goes and its ok for another 10 or 15...if i switch back to the front tank when the light comes on it gets its power back and the light goes off and shift problems go away.