A puzzle for you GM experts

A puzzle for you GM experts

PostBy: david78 On: Fri Jan 21, 2011 9:42 am

Here's my problem: I have a 1996 K2500 Suburban, 5.7, 136,000 miles, automatic. It had been running great, but quit on the way home a couple nights ago, just like turning off the key. I have spark but no fuel. I had to have it hauled home. To add insult to injury, the guy driving the rollback backed into a tree limb while turning around and busted out the back glass. So now I have a three ton lawn ornament that leaks. :mad: Anyway, I couldn't hear the fuel pump run when I turned the key. I put in a new fuel pump relay and changed the filter and now when I turn the key on I can hear the pump running but still no fuel spraying into the TBI. It will start when I pour gas into the TBI, but quits as soon as that fuel is gone. I had replaced the fuel pump a couple years ago. This is my building material/coal hauler so I really need to get it running. Any ideas?
david78
 
Baseburners & Antiques: Fuller & Warren Splendid Oak 27
Coal Size/Type: Nut

Re: A puzzle for you GM experts

PostBy: Blackrocks On: Fri Jan 21, 2011 9:56 am

just guessing ....pluged fuel filter?
no gas in tank?
Blackrocks
 
Hand Fed Coal Stove: Hitzer 503 insert
Coal Size/Type: Nut --- bagged

Re: A puzzle for you GM experts

PostBy: david78 On: Fri Jan 21, 2011 10:02 am

I'm a good one to assume it's the most expensive, hardest to replace part and overlook the obvious, but I put a new filter in, and have 3/4 tank of gas, so it's not going to be that easy. :lol:
david78
 
Baseburners & Antiques: Fuller & Warren Splendid Oak 27
Coal Size/Type: Nut


Re: A puzzle for you GM experts

PostBy: Sting On: Fri Jan 21, 2011 10:07 am

do you have pressure in the fuel rail up to the TBI?
Sting
 
Other Heating: BurnHAM=NG-gas

Re: A puzzle for you GM experts

PostBy: david78 On: Fri Jan 21, 2011 10:13 am

I don't have a pressure gauge, but when I push the valve at the test port, I get a good stream of fuel squirting out.
david78
 
Baseburners & Antiques: Fuller & Warren Splendid Oak 27
Coal Size/Type: Nut

Re: A puzzle for you GM experts

PostBy: Rob R. On: Fri Jan 21, 2011 10:19 am

If you can hear the pump run, it is probably not a wiring/relay problem. More than likely the fuel pump is shot.

-Rob
Rob R.
 
Stoker Coal Boiler: EFM DF520
Hand Fed Coal Stove: Hitzer 50-93
Other Heating: Dad's 1953 EFM Highboy

Re: A puzzle for you GM experts

PostBy: cabinover On: Fri Jan 21, 2011 10:27 am

Yeah but he said he gets fuel at the schrader valve. And he can hear his pump running. If there is pressure there it has to have pressure at the TB. Bad ECU maybe?
cabinover
 
Stoker Coal Boiler: Hybrid Axeman Anderson 130
Baseburners & Antiques: Sparkle #12
Coal Size/Type: Pea, Buckwheat, Nut
Other Heating: LP Hot air. WA TX for coal use.

Re: A puzzle for you GM experts

PostBy: SMITTY On: Fri Jan 21, 2011 10:53 am

Those things are very picky about fuel pressure. It should be 55-65 psi .... any lower & it won't run, even if you have fuel.

Remember when a fuel pump was $15 and took 10 minutes to change??? :mad:
SMITTY
 
Stoker Coal Boiler: Patriot Coal - custom built by Jim Dorsey
Hand Fed Coal Stove: Harman Mark III (not currently in use)
Coal Size/Type: Rice / Blaschak anthracite
Other Heating: Oil fired Burnham boiler

Re: A puzzle for you GM experts

PostBy: david78 On: Fri Jan 21, 2011 11:09 am

Yeah, I'm seriously thinking about getting rid of the Sub and finding a 70"s Dodge Power Wagon; something as simple as I am. ;) I've always liked the looks of those old beasts. Anyway, if it's low fuel pressure, would you think pump? Fuel pressure regulator? The thing that puzzles me is that it just suddenly quit with no symptoms at all. When the pump went out before, it ran poorly off and on for a couple months and never did die completely. Just makes me think electrical with it just shutting off like that.
david78
 
Baseburners & Antiques: Fuller & Warren Splendid Oak 27
Coal Size/Type: Nut

Re: A puzzle for you GM experts

PostBy: SMITTY On: Fri Jan 21, 2011 11:10 am

Very well could be the regulator. Seeing that's cheaper & easier than a pump, I'd replace that first. Wouldn't hurt to grab a pressure gauge though before throwing parts at it.
SMITTY
 
Stoker Coal Boiler: Patriot Coal - custom built by Jim Dorsey
Hand Fed Coal Stove: Harman Mark III (not currently in use)
Coal Size/Type: Rice / Blaschak anthracite
Other Heating: Oil fired Burnham boiler

Re: A puzzle for you GM experts

PostBy: Sting On: Fri Jan 21, 2011 11:13 am

Without test equipment -- you may as well play with your self and leave your credit card at the parts store

If you have pressure with the regulator stopped the pump is good - when the regulator is in line and pressure is bad - the regulator is in question

but it could be 12 other things too

See -- you need tools for any job
Sting
 
Other Heating: BurnHAM=NG-gas

Re: A puzzle for you GM experts

PostBy: SMITTY On: Fri Jan 21, 2011 11:17 am

^^^ Very true!

I recall some of the S10's having a vacuum line to the regulator that you could disconnect, & see if it stalls or keeps running ...... but I'm not sure the 'burban has that ....

If it does, & you see fuel in vacuum line, it's bad.
SMITTY
 
Stoker Coal Boiler: Patriot Coal - custom built by Jim Dorsey
Hand Fed Coal Stove: Harman Mark III (not currently in use)
Coal Size/Type: Rice / Blaschak anthracite
Other Heating: Oil fired Burnham boiler

Re: A puzzle for you GM experts

PostBy: Poconoeagle On: Fri Jan 21, 2011 12:49 pm

two things well three

efi relay and or fuses two 10 amp ones
ignition switch
smack the ecm...
Poconoeagle
 
Stove/Furnace Make: Buckwalter & Co. , EFM520
Stove/Furnace Model: No. 28 Glenwood 1880, Alaska

Re: A puzzle for you GM experts

PostBy: 009to090 On: Fri Jan 21, 2011 1:56 pm

I believe its the ecm. A buddy of mine had the same problem with his Suburban. It was driving him crazy, just dying in the the middle of traffic. He replaced several of the common items mentioned above, until someone told him which part was causing the issue.
I'll get more details from him and post it here.

Edit: check for PMD failure. I think it costs about $80
009to090
 
Stoker Coal Boiler: EFM 520 HighBoy
Hot Air Coal Stoker Stove: DVC-500 x 2
Coal Size/Type: Anthracite Rice

Re: A puzzle for you GM experts

PostBy: 1ton On: Fri Jan 21, 2011 2:07 pm

I’ve had the same thing happen on my S10 Blazer, 1) was the replaced fuel pump Factory or after market? The 1st one I put in was aftermarket and lasted about a year it failed to make pressure, So the 2nd one was dealer part and that worked fine, I’ve heard that aftermarket one’s have a tendency to fail, it’s a 50/50 shot.

On the top of the engine there is a red wire (on GM’s) if you look in the shop manual you’ll should find it, it is to test your pump to hear if it runs, you can use this to test pump pressure to see if that ( aftermarket) pump is pumping.and at the specs.

Good luck
Been there
1ton
 
Stove/Furnace Make: Clayton
Stove/Furnace Model: 1600