NEED HELP Turns over, won't always start

[Jonzy]

My 2003 Envoy I6 will run all day, but after I've driven it for a while and shut it off, sometimes won't start without difficulty. I find I have to pump the gas but that doesn't work every single time. Sometimes it will turn over and not start and I have to leave it alone for a while before going out and starting it again. Like I said, once it's running it will run all day. If I shut it off and start it immediately it will always start. But if I leave it for 10 mins or so it may not fire.

Tried switching ignition relay and no change. Tried disconnecting command start, no change. No engine light now, but occasionally get a 440 code which has something to do with fuel cap I think?

Any suggestions?

Jon

 

[Mooseman]

Welcome to the Nation! Wish it was under better circumstances.

When you try to start it, do you always hear the fuel pump prime? Does it always crank?

I guess you mean a P0440 code? Yes, the gas cap is usually the culprit but wouldn't prevent it from starting.

 

[Jonzy]

I hear the fuel pump prime every time, and it always cranks. I can always get it to start with difficulty. Sometimes if it doesn't fire I'll wait a couple minutes and try again and it'll eventually start. Like I said once it's running no issues whatsoever. Never stalls.

 

[Wooluf1952]

Welcome

In case you haven't heard:
http://gmtnation.com...eres-the-story/

Is there a strong gas smell when you turn it off? I had that same problem when my fuel pressure regulator went bad.

 

[budwich]

check your fuel pressure and go from there.

 

[Mooseman]

X3. Sounds like a fuel supply issue.

 

[Jonzy]

Since I've been looking into it everything has been pointing to my fuel pressure regulator so far. I found one in a junk yard for 20 bucks so it's not a pocket breaker.

Thank you for your replies. I'll be back in here if it's not the issue.

 

[Mooseman]

You can still come back if it is

 

[budwich]

you will be back... the fuel regulator is only "one part of the problem path".

 

[Jonzy]

Changed the fuel pressure regulator on Friday. Problem solved! Starts perfectly every time. Thanks for the quick replies guys!