I suggest anyone who has a TBI vehicle to get this Harbor Freight Fuel Pump Pressure testing kit. Many Fuel Pump or Fuel Injection service kits do NOT come with the TBI adapter. This cheap $44 kit does. There is no pressure tap on TBI engines to test for fuel pressure. So this fitting goes inline using the threads to the fuel filter. Then you can attach the pressure gauge to the fitting.
The last TBI truck I worked on, ran like hell. The guy that started working on it was a parts changer and just started changing things and never found it. I'll admit, we both and another mechanic said, it's not the fuel pump. We knew it had been replaced a couple years ago and had very few miles on it, and it didn't act like a bad fuel pump. In most cases, they either work or they don''t and the truck ran, it just ran very poorly. Finally I said for ***** and giggles, we need to do a fuel pressure test. Turned out to have 4psi. That's not enough for TBI.
What pissed me off more than anything, was I told my dad, don't let that shop iinsall anything but a Delphi or AC Delco pump, I don't care if they have to buy it at a dealership and spend big money on it, but don't get a crappy AirTex pump from one of the discount chains. He was out of a town at his house, and I couldn't get to it for a few weeks. But now we have this problem. Turned out to be a POS discount auto fuel pump that I said NOT to install. So I did get the Delphi pump at Advanced Auto believe it or not and the truck has been fine since. We didn't regret replacing all those sensors and cleaning the EGR and ICM etc. The truck is a 94 model and never had a thing done to it, except plugs and wires changed once, a clutch, a fuel pump, alternator and several batteries. That's it. So we also changed plugs and wires again, cap, rotor and distributor, an AC Delco distributor. That thing has to have well over 200,000 miles on it and runs like new, not a bit of smoke which blows my mind. I'd expect at leat valve seals to be leaking by now but we've never been in the engine either. I expect if anything goes anytime soon, it's about time for a timing chain and gears.
But yeah, get this $44 Kit from Harbor Freight.
https://www.harborfreight.com/basic-fuel-injection-service-kit-64939.html <<<<<LINK to Kit.