My 02 2500 since day one has been hard to start. I changed a purge valve and it helped a little, but typically you can crank and crank and crank and eventually it goes, or crank it 5-10 seconds, stop, crank again and it starts.

I've occasionally noticed a gas smell before but no drip until last Sunday I got in, drove about a mile, shut off and I notice a puddle under. By the time I see it it's not leaking and when I start it and let it run no leak. It seems to have burped out after I shut it off, and is roughly under where the fuel inlet is, but it's hard to tell where it may have come from due to the plastic shield on the tank. Showing below half on the gauge.

Could I be looking at an issue with a return fuel line, maybe a crack that now that it's gotten cold is more open, that lets the fuel leak down when I shut it off?

The problem is it's very irregular and now that I've been watching for it I don't see it. When I do notice it, it varies even how much fuel comes out. Fuel level doesn't seem to matter, either, I had it full and never noticed anything. Of course even a big puddle evaporates in a few hours, so it could leak and I never see it.

And even the hard start is irregular, sometimes I turn the key and it fires right off normal.

This thing is a beater and I hate to put much time or money into it, but until used car prices drop I'm staying with it. I can't replace it for what I paid for it.

 

Nothing on this? I notice a fuel smell here and there but no more puddles.

 

put a fuel pressure gauge on the fuel rail schrader valve. prime the system...watch for pressure leakdown. if the rail has to prime before starting....you will have a long crank time. if its an external leak...find and fix obviously. if its internal the most likely fault is the fuel pump check valve.

 

Well I think the fuel pump just quit entirely; it won't start, coughs and sputters a little and quits. Thank goodness it's in my driveway. Live data on the scan tool shows two fuel voltage readings and both say OL (overload, I presume), which is the same as the dead clunker I looked at over the summer and passed on buying. It was whining a bit and I considered changing it, but my back has been messed up for a while now so I didn't want to screw around dropping the tank. I guess I can cut a hole in the floor though, somebody on youtube did it that way.

I have a HF fuel pressure tester kit which I could use as you suggested to verify the pressure, but I'm almost scared to try to use it, the reviews on it I have 50-50 odds it will leak fuel all over and not really tell me much. Maybe I can rent a better one from Autozone or somebody.

 

Jeeze Rock Auto has an Airtex fuel pump for under $20 because it's a closeout. I probably want the AC Delco OEM replacement though for about ten times as much.

 

purpose of the check valve is to keep the fuel rail filled with fuel....when it fails the fuel pump still pumps fuel...it just causes a long crank condition

 

Yes, but as I mentioned the live data in the scan tool shows two fuel system voltage readings as OL, which I presume means overload and something is shorted out - unless it could also get that from being unable to push fuel through the system. However I got that same reading on the other van I looked at without ever being able to crank it at all, it's battery was very dead.

It now does not really run regardless how long it cranks, it pops a little bit and quits. Which tells me it's getting a little bit of fuel but not enough to run. Until today, it would always start, it just sometimes required to crank a few seconds, stop, then crank again.

The fuel lines on these are mostly plastic up to the back of the engine, from there they're metal, so it's not likely they're rusted out. I had guessed perhaps it burped fuel out the evap line somewhere.

I suppose I should try changing the filter, it could be clogged or restricted or maybe even has some water in it which froze.

 

Okay I'm reading it wrong. OL is just telling me it's in open loop.

I'm used to the OBD-1 stuff on the TBI trucks, I've never had to diagnose OBD-2.

Regulator could be an issue, it has a lot of the symptoms for that. Here again I guess the first step is check the fuel pressure. If it's good then look at the regulator. If it's bad, then the pump.

 

if you have a fuel system with a return hose to the tank...the regulator should be near the fuel rail with a vac hose to the manifold on it. pull the vac hose off and inspect for fuel. the hose should be dry. if it has fuel, the diaphram has ruptured.
if no fuel is detected at the hose and fuel pressure is ok...the regulator is fine.

if you have no return hose...the regulator is part of the fuel pump.

 

It's a 2002 Express van, 5.7 EFI. Same system as most 96-99 trucks with some carryover to 00 and 02 depending on model. The fuel pressure regulator is under the upper intake manifold. It's hours of work to get to, for a part held on with a clip that itself takes maybe 5 minutes to change. Because it's a van it may even require removing the alternator and other things on the front for access and clearance to remove it. Then, you have to use a lot of caution because there's a lot of plastic parts in there including said intake. Some of GM's wonderful engineering.

I didn't have time today to take the doghouse off, you have to do that to access the test port, but I did crank it some more and it's pretty clearly not getting any fuel at all at this point, I hear no sound from the fuel pump either.