got ahold of a pressure gauge today and tested my fuel pressure, I came up with 20-22psi at my rails with vacuum line disconnected, this is TPI, the pump was new by the way, I know it should be in the 40psi range, so either I'm dealing with a faulty gauge or does this sound like I was sold a TBI fuel pump, the car almost sounds as though its running on 4 cylinders. Im going to try and make a adjustable fuel pressure regulator cap since I have a few of them laying around

 

been reading all the leak down tests for TPI, what exactely goes bad in the regulater to cause this 20psi at the rails I am exxperiencing, by the way, 20psi is what I get while car is running as well< Im really hoping its not the fuel pump, will start crimping lines today and see what happens, the injectors were new so I pretty sure thats not the problem, after pump shuts off, my pressure drops to zero immediately, this is a cold start tpi unit that has been converted to speed density, so I will try a plug the injector to eliminate it as a cause ........ any other advise you guys have

 

can you crimp the return line and see if the pressure goes up to 90-100 psi.

 

May be filter related as well, after filter and fuel line crimp, if still 20 PSI, better recheck the p/n they sold you. I recall someone else getting a TBI pump for thier TPI as well, had about the same pressure you're seeing.

If that's the case, hope you make the counter guy buy you a case of your favorite beverage for the hassle to RandR it again

 

lets talk resistance of the injectors for a second, so far mine are in the range of 16.9 - 17.1 ohms, is this about right

 

well pinched the return line, still rails at no more than about 20psi, and still after car was shut off fuel pressure dropped immediately yes the fuel filter is on correctly, and 14.2 volts at the pump harness ....... sounds like I'm dealing with a TBI pump doesn't it, I have a freeze plug for the cold start injector so going to see if it's stuck open, with key on engine off should I have power at 1 terminal of the injector and while cranking I will see a flashing ground signal at the other correct

 

check for power at my injectors, key on engine off, around 12 volts at both injector terminals ..... this doesn't sound right does it ? ..... however with car running they still have power to both yet when I used a test light looking for a ground the light lights up very dimmly on one of the terminals ...... I'm missing my carburator more and more, I'm going to get one of those injector testers maybe that will confirm a problem better

 

well stopped by the parts store once again and purchased a NOID light and a second fuel pressure gauge, end results

drum roll please ........

NOID light flickers ........ fuel pressure 17 psi

I purchased a TBI pressure gauge this time since it has better pressure readings under 30psi.


so I guess I'm dropping the fuel tank again ANY VOLUNTEERS and by the way I purchased a 87 350 engine code 8 fuel pump, this is a tuned port 350 correct ? and no the cold start injector isn't leaking at all

 

if i was closer id give you a hand ,but cali is just a bit too far..at least you know the injectors are firing,sounds like its a tbi pump.

 

well got the new pump in right now, during fuel prime I get around 30psi at my rails, turn the key to start and immediately fires and fuel pressure jumps to just under 45 psi, I also noticed the car goes into higher idle when its cold now, something it never did before, tomorrow I will finish the car and take it for a whirl.


thanks guys

 

well took my baby for a spin, seems to run very strong, how, after running it with a muffler eliminator setup I made just way to noisy for me so it's definately coming off, another problem is the 2.73 gears in the car, while it pulls good it's still has a hard time spinning it's tires from a stop, don't get me wrong it will do it but slipping the clutch is necessary, are stick shift cars with 2.73 like this, also I get a code 43 now to, I had this awhile back just have to have another brain fart to bring my memory back, I have a 373 disc rear end at my dispossal so I think that will definately bring the car to life off the line