2003 1500 5.3, long crank time??

[Cornfield creations]

We have this truck in the shop that we did some work to:
Replaced- plugs, wires, fuel filter, and did an intake/fuel injection cleaning-

Came in with a long crank time, usually would take 3 tries to start- after replacing those parts it starts up faster, but not as fast as they normally do. It only does it when it sits for at least 20 minutes.

It runs good otherwise.

Could this be partially clogged injectors still? I know there are some GM techs in here and Mitchell is giving me nothing-

Thanks in advance!

 

[bigbadchev84]

pull the hose off of the fuel pressure regulator, if fuel comes out of the line you have a hole in your diapghram. I just went through this with our 2000 tahoe. Start right up in the mornings, but after sitting for a while it would crank and crank, fire up, stumble a little bit, clear out and be fine. The vacuume hose sucks extra fuel through the diapghram and floods the motor. I was getting worse than normal mileage and was getting a slight stumble at idle.

 

[Madspeed]

Bring it to a qualified technician
Ok ok so im a dick. check to see if fuel pressure drops off after you shut it off. if not you either have a leaking injector or fuel pressure regulater. If thats not it repost and ill tell you more.
But seriousley. Dont throw parts at a car, find the reason first and youl look like a pro

 

[4X4HIGH]

My guess would be a leaking injector causing a "flooding state" so a longer crank time to start but would run perfect afterwards.

 

[Cornfield creations]

Well we're not throwing parts at it. He has 122,000 miles and never had a tune-up so he wanted that done anyways. He was just hoping that would take care of it.

I'll get the pressure gauge on it and see what comes up.

 

[Ck1500]

i had this on a 2000 chevy with a 5.3 and it changed out the fuel rails.. and now it starts up like it should... barely a bump of the starter...

hope this helps

Ck1500

 

[diesel4me]

GM had some problems with fuel rails rusting internally,but wont admit it and replace them under a silent recall..not saying this is your problem,just a heads up!..my brother had an '03 GMC that has "misfire" codes on cylinder # 3,and it was not an ignition fault--he replaced the injector and it ran great,no codes--for 3 days,when another cylinder started misfiring..frustrated ,he contacted a friend at the local GMC dealer who was a long time tech,and he said if it had about 100K miles,he'd replace the rails..said he'd seen some clog with red silty rust with as little as 25K on them,and the tiny screens made into them plug solid and cant really be cleaned--some rusted thru and leaked and caught the engine on fire too!..

My brother had them fix it,his company has learned sometimes its best to send out difficult to diagnose jobs and just let him do the routine maintenence,though he is a good mechanic and certified..when he picked the truck up at the dealer,his friend said "here is the old fuel rails,cut them open and let me know what you find"..he did,and they were a;; red and rusted inside,just as he'd predicted..outside they looked as shiny as day one..guess GM used recycled crap steel ,or ethanol dont like the blend they used??..

 

[ryan22re]

If there is debris in the fuel rail, it more than likely came from the fuel pump.

If the fuel pressure is bleeding down or slow to come up, it could also be the fuel pump. Watch the gauge while keying on, it should come up rather quickly, and shouldn't bleed down too much. If you could pressurize the system and then close off the lines to and from the engine, you can determine if the injectos/regulator are bleeding down, or if it's the pump.

 

[YZEATER]

i had a '99 silverado with a 5.3. it started doing the same thing and i pulled the line off the fuel pressure regulator and it had fuel in it. so i replaced it and it was fixed.

those trucks also had fuel pump problems.