My dad's 94 had a problem that literally kicked the dog snot outta me and another self taught mechanic. I'd consider him more knowledgable that me on the more modern stuff so I thought.... At any rate, he replaced some parts, like MAP, EIM, cap, rotor, plugs, wires, I replaced the fuel filter, IAC, etc, I know I'm not listing all we replaced and to no avail getting the issue solved. The fuel pump had been replaced about 2 years ago and in that 2 years, I bet my dad has not put 5000 miles on this truck. 2 other REAL mechanics my dad had talked to said, No, it's not a fuel pump, it's idling fine and low rpm is fine, which myself and this other guy helping my dad out agree, No, it's the fuel pump and it's new anyway, it's not the fuel pump. I finally replaced the whole distributor and some parts in the TBI, top gasket etc, which did have a tiny vac leak. Figured we're not wasting money, this is a 94 and my dad has done nothing to this truck, but a fuel pump, a clutch, and it seems like I did the cap, rotor, plugs and wires about 10 years ago. That's it. So whatever got replaced needed it anyway and we didn't waste any money and with every part replaced it ran better and better but still had this bad bog as soon as you hit 3rd gear and then it started bucking, losing power and acting stupid, so couldn't drive it past 2nd gear, and this is a granny 5 speed, so really couldn't even get it out of first gear. After replacing all this BS over a period of about 2 months and not fixing it, I told my dad, I'm at a loss and defeated. I don't have a fuel pressure tap for the filter to test fuel pressure on TBI, but finally went HF and just bought a cheap azz fuel pressure test kit since it had the tap I needed. Damn, if the fuel pump wasn't putting out just under 5lb of pressure. Now I told my dad, like I tell everyone, DO NOT go with those POS aftermarket in take electric fuel pumps. Go AC Delco or Delphi, or NOTHING. So I asked if he told his last REPUATABLE shop that he wanted an AC Delco of Delphi pump. He said, probably not but maybe I don't remember. So replaced the POS Airtex pump with a Delphi and the truck has been running like brand new the last 4 months now that we've replaced everything except the internals, rings, bearings, etc but still no smoke and plenty of compression so it'll probably go another 10 years at least before it needs anything.
