5.0 starts, wont keep running
merrimack
10-05-2014, 07:36 PM
Gentlemen (and ladies) my problem is this; 2000 GMC Savana 3/4 ton van, 5.0 TBI, 148K . I recently retired and the van sat for about a year. Charged the battery and tried to start it and it started right up (that's the good news), The bad news is it wont keep running. It started and instead of idling it went dead. I waited a few seconds and tried again, it started right up then just as the first time died, wouldn't take throttle. I pulled the dog house and hooked up my fuel pressure gauge and turned on the key went to 60 psi. started the engine and immediately died. tried the key in run position and had 60 psi repeatedly. The engine will keep running with starting fluid sprayed into the throttle body, key in run position after starting. NO trouble codes, hard or pending.
I am not much of a mechanic, ( I was a hell of a builder ). I am leaning toward the fuel pump but cant justify the 60 psi at key up then die.
Any ideas would be greatly appreciated. Also has any body had experience with Napa brand fuel pumps or should I bite the bullet and go for the Delphi, if that's what it comes down to.
sorry for the long post, I wanted to cover all I did to remedy the situation. :frown:
I am not much of a mechanic, ( I was a hell of a builder ). I am leaning toward the fuel pump but cant justify the 60 psi at key up then die.
Any ideas would be greatly appreciated. Also has any body had experience with Napa brand fuel pumps or should I bite the bullet and go for the Delphi, if that's what it comes down to.
sorry for the long post, I wanted to cover all I did to remedy the situation. :frown:
maxwedge
10-06-2014, 09:35 AM
60 psi is ok, I don't know why you would think the pump is bad, how recent is the fuel filter?
merrimack
10-06-2014, 04:29 PM
thank you Maxwedge for the quick reply. As I stated in the original post I'm not much of a mechanic but I can replace parts once I have a reasonable diagnosis. I am going to replace the fuel filter on Thursday this week I'm hoping it will be a quick (read cheap) fix, but my luck ........ anyways, if the filter doesn't work could you or others direct me in another direction or possibility. I would greatly appreciate it.
I really didn't think it was the pump with 60# at the fuel rail but as you know helpful neighbors all have an opinion and none are mechanics I'm shure you know the drill.
With the fuel pressure regulator under the intake manifold is there a way to test the regulator without pulling the manifold. Or would a bad regulator not allow 60# at the fuel rail.
I really didn't think it was the pump with 60# at the fuel rail but as you know helpful neighbors all have an opinion and none are mechanics I'm shure you know the drill.
With the fuel pressure regulator under the intake manifold is there a way to test the regulator without pulling the manifold. Or would a bad regulator not allow 60# at the fuel rail.
maxwedge
10-06-2014, 07:09 PM
Usually if the reg. was bad it would drop off pressure pretty quick when shut off.
merrimack
10-07-2014, 08:20 AM
Thanks again Maxwedge. I'll post results after the fuel filter replacement.
merrimack
10-07-2014, 10:30 AM
Hi Maxwedge; a quick thought, how do I determine if my 2000 gmc savanna 3/4 ton van has a factory security system? There is no chip in the key. I'm thinking the computer or security system is thinking the van is being stolen and shuts off spark or would that system shut off power to the fuel pump. I may get a chance to replace the fuel filter this afternoon.
Again thanks for you help and patience.
Again thanks for you help and patience.
merrimack
10-07-2014, 02:26 PM
Hi Maxwedge; The fuel filter did nothing different for me. Any more ideas would be appreciated.
maxwedge
10-07-2014, 04:13 PM
You say TBI but isn' this cpfi with the injector unit under the intake. the tbi is for throttle only, no?
merrimack
10-07-2014, 07:47 PM
You may be right on the carb, as I said I'm a back yard mechanic.
Rethinking the prior post, I don't think the security system would be the problem because the engine will run past start-up with the aid of starting fluid shot into the intake.
I'm stumped at this point. I'm getting fuel, air and spark and she starts every time I turn the key she just won't keep running. the fuel pump when I extend the run with starting fluid only drops to 55-57 psi. I read somewhere the bottom end of the operating range for fuel pressure is 50 psi. You may know better.
Any more ideas would be appreciated.
Also what are your thoughts on the fuel pressure regulator, if the regulator was bad would that allow the rail readings or just pass thru the fuel rail and go back to the tank
Rethinking the prior post, I don't think the security system would be the problem because the engine will run past start-up with the aid of starting fluid shot into the intake.
I'm stumped at this point. I'm getting fuel, air and spark and she starts every time I turn the key she just won't keep running. the fuel pump when I extend the run with starting fluid only drops to 55-57 psi. I read somewhere the bottom end of the operating range for fuel pressure is 50 psi. You may know better.
Any more ideas would be appreciated.
Also what are your thoughts on the fuel pressure regulator, if the regulator was bad would that allow the rail readings or just pass thru the fuel rail and go back to the tank
merrimack
10-07-2014, 07:58 PM
Another question is where does the fuel pressure regulator get its vacuum from or does it work differently because its under the intake manifold.
merrimack
10-07-2014, 08:33 PM
You are right on the injection being cpfi, my mistake.
merrimack
10-07-2014, 09:57 PM
I'm leaning towards the fuel injector being clogged with the old fuel I know the fuels today can get real nasty. I am still confused about the repeated quick starts, do you know if this 2000 5.0L has an enrichment injector for cold start-ups? Would that explain the easy start then no run?
maxwedge
10-08-2014, 09:42 AM
Check into the fp requirements for that engine, it may be 65,those systems were trouble some partticularly the spider assy. There is no special enrichment component.
merrimack
10-08-2014, 11:33 AM
Thanks again for the info. Where as the engine starts right up but won't keep running do you think the old gas is an issue? There was 1/8 of a tank (one year old) when I first tried to start it, I put 5 gals of fresh gas in a week ago and still the problem exists. Could the injectors be gummed up and why would it start right up as normal, seeing their is no enrichment device to prime the engine? I'll find the stats for the fuel pump and get back to you.
merrimack
10-08-2014, 11:46 AM
The book calls for 60 psi at the fuel rail that's what I'm getting.
maxwedge
10-08-2014, 07:53 PM
To save guesswork here maybe tech should help uou with this. Sounds like the injector unit may be a?t fault.
Jerrykirby94
11-11-2014, 08:07 PM
Have you ever thought it could be a dead cell in your battery? Sometimes it really is as simple as that. Check to see if your battery is fully charged and does not have a dead cell, a dead cell will cause the vehicle to start but does not have enough amperage to keep the engine running.
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