No Start - Have spark, no fuel. Ether will turn it over
What is the g in psig? Are you using a fuel pressure gauge on the Schrader valve or are you testing vacuum at the line going to the fuel pressure regulator?
PS - The fuel pump also runs while cranking.
PS - The fuel pump also runs while cranking.
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The g stands for "gauge". Usually psi & psig are used synonymously to mean the measured pressure not including atmospheric pressure, the latter always being represented as psia and never as psi. A gauge at 0 psig already includes the atmospheric pressure and removes it from the equation. I am measuring the pressure off of the fuel connection, not the vacuum connection.
From what you've explained, the fuel delivery system must be functioning correctly. I turned the engine off and the pressure remained the same after 30 minutes, so the Schreader valve must be working. In addition, when I remove the vacuum hose, the pressure rises to 50 psig.
Tomorrow will be normal work day and I have physical therapy afterward (lower back problems) so I will leave the findings here tomorrow evening.
Later guys and thanks!
From what you've explained, the fuel delivery system must be functioning correctly. I turned the engine off and the pressure remained the same after 30 minutes, so the Schreader valve must be working. In addition, when I remove the vacuum hose, the pressure rises to 50 psig.
Tomorrow will be normal work day and I have physical therapy afterward (lower back problems) so I will leave the findings here tomorrow evening.
Later guys and thanks!
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Well, I have a little time this morning for an update on this mornings commute.
Same thing, hard starting, car stalls when backing out, restart car, car stalls 1 mile out of town. Didn't act up at all the rest of the way. No SES light at all, even when the engine died.
Now it will sit for 9 hrs in the parking lot, then it'* off to therapy where it will sit for 1-1/2 hrs. I try to compare the difficult starting to the amount of time it sits to see if there is any correlation.
Thanks for everyones help.
Same thing, hard starting, car stalls when backing out, restart car, car stalls 1 mile out of town. Didn't act up at all the rest of the way. No SES light at all, even when the engine died.
Now it will sit for 9 hrs in the parking lot, then it'* off to therapy where it will sit for 1-1/2 hrs. I try to compare the difficult starting to the amount of time it sits to see if there is any correlation.
Thanks for everyones help.
Reread the post to date.
There are a couple things I see as possibilities here and a couple of them are far from free. First off, there have been a couple of people that had similar issues and found the ground buss by the drivers left foot to be corroded. There'* an article in Techinfo on how to clean them up and where they are located. I would do that, strictly based on ensuring you exhaust the possiblility.
Then it'* a question of which do you want to try replacing first. A usually tough to kill ICM or a normally flukey at best PCM? The 94/95 PCM'* are known as the worst years for a pcm. If you have a junkyard local...most H body'* 94 or 95 will work if you change out the chip in the pcm.
There are a couple things I see as possibilities here and a couple of them are far from free. First off, there have been a couple of people that had similar issues and found the ground buss by the drivers left foot to be corroded. There'* an article in Techinfo on how to clean them up and where they are located. I would do that, strictly based on ensuring you exhaust the possiblility.
Then it'* a question of which do you want to try replacing first. A usually tough to kill ICM or a normally flukey at best PCM? The 94/95 PCM'* are known as the worst years for a pcm. If you have a junkyard local...most H body'* 94 or 95 will work if you change out the chip in the pcm.
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Originally Posted by markkleb
I think 42 psi is the right spec.
For the 1995 L36 its 48-55 PSI...
He is falling within spec... He can drop a few below the spec as this will be normal with full vac applied to the Regulator..
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Not sure if this will help or mean anything... But this is what your pump should sound like and the length of time it should run when the ignition is cycled on.. Should start like this as well.

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How much better can you get - thank you.
Today was not too bad. As I reported this morning was typical. At lunch I went out to start her up. The first time nothing. The second time started right up. I turned on the AC and cooled off. After work took two tries, and after therapy it ook a few more.
I bought a new fuel pump relay when I returned the scanner. I'll put it in tonight.
I checked the grounds as suggested. They are pristine - truley showroom quality! Since I had the trim removed I thought I'd replace the relay.
Thanks for all of the info... I'm still looking. I'm calling the yards tomorrow for an ICM to trade out.
Today was not too bad. As I reported this morning was typical. At lunch I went out to start her up. The first time nothing. The second time started right up. I turned on the AC and cooled off. After work took two tries, and after therapy it ook a few more.
I bought a new fuel pump relay when I returned the scanner. I'll put it in tonight.
I checked the grounds as suggested. They are pristine - truley showroom quality! Since I had the trim removed I thought I'd replace the relay.
Thanks for all of the info... I'm still looking. I'm calling the yards tomorrow for an ICM to trade out.
Thanks for explaining PSIG/PSIA.
I thought of something else that can disable the fuel injectors. When the gas pedal is pressed while cranking the PCM goes into 'clear flood mode' & disables the fuel injectors. A faulty throttle position sensor could put the PCM into this mode without the gas pedal being pressed.
Have you tried checking for fuel injector pulse?
I thought of something else that can disable the fuel injectors. When the gas pedal is pressed while cranking the PCM goes into 'clear flood mode' & disables the fuel injectors. A faulty throttle position sensor could put the PCM into this mode without the gas pedal being pressed.
Have you tried checking for fuel injector pulse?
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Originally Posted by Technical Ted
Have you tried checking for fuel injector pulse?
I replaced the fuel pump relay. No difference. One more thing off my list.
Is it possible for the ICM to see a high enough RPM to hand off to the PCM without the fuel injectors firing?
Originally Posted by jr's3800
Not sure if this will help or mean anything... But this is what your pump should sound like and the length of time it should run when the ignition is cycled on.. Should start like this as well.
I'll be calling around tomorrow for an ICM. I have the Delco coils. It looks like the ICM is the same for a Delco or Magnavox coil pack?





