06 Silverado (odd start)

[OtisBlkR1]

Im tinkering with the "garage queen" again, My Silverado sees very little use only coming out of the garage every few weeks. Its flawlessly maintained. I noticed recently that while cranking the motor over (5.3) that it seems to hesitate at the very end (while holding the key starting it, just as the engine starts to fire, it seems to bog just slightly) It starts quickly, and no hesitation while running. Im clueless as to what could be causing this. 86,000 on the clock, 80,000 plugs changed last, fresh battery. up till last year it was getting a yearly dose of Techron to keep things clean. Premium fuel 70% of the time.

My thoughts were possible the fuel pump getting weak on me.

your thoughts

 

[SatinSilver]

Top tier fuel from a newer, busy station with regular grade. I'll suggest Shell. Nice, long hwy trip....25 miles out and then back. Clean and lube connections to the battery. Maybe some Stabil in the tank. Clean throttle body.

 

[Thermo1223]

Does it require premium fuel? Because outside of using a higher octane than it requires I can't foresee a reason it would do that.

 

[OtisBlkR1]

no, the 5.3 ltr is a tractor motor.. regular unleaded is all that's required.

 

[Ramblejam]

Originally Posted By: OtisBlkR1
regular unleaded is all that's required.


It'd be awful fun to watch the look on your face when you found out how much timing was being pulled via knock retard...

 

[barkingspider]

I would use 87 octane and I would drive it more than once every couple of weeks.

 

[Delta]

My 4 banger S10 does the same thing, I'm chalking it up as needing a new fuel pump here sometime. The truck will sit at work all week when I'm out in the company truck. Has a real hard time catching itself and stumbles like you describe. If it's daily driven then there is no issues. Key on/off a couple times to cycle the fuel pump seems to help alot. I've started using TC-W3 every fill-up and it seems to be starting better, not to mention running better.

 

[Rhymingmechanic]

I'm not sure whether it applies to your truck, but a bad fuel pressure regulator could cause hard starting on the earlier Silverados.

 

[OtisBlkR1]

Topped up the oil with a bit of MMO, added a can of seafoam, drove about 150 miles. came home, changed oil.. not claiming that any of this is related, However the "blip" has disappeared. I think it may have just needed driven. anyway, all is well in the Silverado world again

 

[OtisBlkR1]

I drove two full tanks of premium fuel through it and a can of seafoam, if its daily driven there is no hiccup, if I let it sit for a week and then drive it, upon the first start of the day it does that weird starting.. so im back to perplexed.. Im not sweating it.. its just odd.

 

[mk378]

There is a check valve in the fuel pump to stop the fuel from draining out of the line (it would go back into the tank) while the truck is parked. The fuel pressure regulator is also supposed to close off completely to keep the line full while parked but it doesn't always.

Workaround is what Delta said, click the key on and off a few times to prime the line before trying to start.