Now I am trying to build my own fuel pressure gauge. I have the gauge, plenty of them, but I need to adapt the Schrader valve on the fuel rail to
1/4" NPT or 1/8" NPT. I called a bunch of automotive shops, a/c part suppliers, fluid power suppliers, etc. etc. No one can find this thing for me, and half the people don't know what it is I am talking about.
Once again, old retired electrical guy; take my thoughts with a grain of salt... but somewhat plagiarized...
Check the fuel line from the tank to the pressure regulator, looking for pinched or "improperly sharp bends" in it... Obvious, I guess - but also look for leaks.
Check the vac hose that feeds the regulator thoroughly, and it's source. Disconnect it (engine running) and verify there's vac.
If you have or can borrow a hand pump, suck the pressure regulator down to 10 or 12 inches. See if engine runs better. See if the vac will hold for at least several minutes without leaking down.
And yikes! Last resort, check for a leaking injector in one of the other cylinders.
All of this relative to "low fuel pressure"
And if that fails - dunno where you are other than Eastern Canada (I'm Winnipeg), but suspect it might be easier/faster/cheaper to let a mechanic who has one just check the pressure for you. Not fix it, just check the pressure. Buy him lunch :)
I'm real lucky; have a little tiny used car lot at the corner. Owned by a licensed mechanic. Fantastic neighbor. Works two ways I guess, went for a bike ride last summer, rode through his lot. Sat evening, threatening to rain heavy, and found an almost new Park avenue with the sunroof wide open. Couldn't close it, but phoned him at home.
As aarc... said: R-12 low side fitting is same as gm port injection large Shrader. Get a R-12 low side hose with female R-12 1/4" Schrader to 1/4" anything else (flare, NPT, etc.) and either use the other end or cut it off and use a hose barb. I suppose you could install an R-134 quick connect fitting on your car and use a R-134 hose. Get one that has a core and permanently remove the old core.
I made the following post back on Oct. 4, 2004. Sounds like we are having the same trouble. I rarely drive the car but was looking at buying a fuel pressure tester from NAPA for about $45.00. Let me know what you find out on yours.
Thanks, Jeff
94 Pontiac SSEi.
The car is showing a miss on the #5 cylinder, occurs only when engine is under boost from the supercharger. Occasionally also shows miss on #4 and less frequently on #6. This was found by using a scan tool.
Have swapped plugs, wires, injectors, injector wires, and coils with those from either #3 or #1 cylinder, but problem stays on #5. Also tried a new ignition control module. Engine runs smooth in the driveway at all rpms. Only misses under load and only under boost conditions.
MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.