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Hard to Start

rmdane2000

By rmdane2000
in Ask A GM Technician

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rmdane2000 New Member

rmdane2000

Posted
Posted

This started about two weeks ago, whenever i get into my truck to start it when its cold, it takes 2 to 3 turns of the key to get it to start. A buddy of mine that works at a Chevy dealership said this happens quiet a bit and that it is almost always the fuel pressure regulator, so i take it to the local shop and they say it doesn't look like anything is wrong the with the fuel pressure regulator, that they think it is the fuel pump. Anybody have any idea? If i do replace the fuel pump and i go with a "performance" fuel pump, any suggestions on the the brand?

 

Thanks!

s-cam Enthusiast

s-cam

Posted
Posted

Actually i was going to post the same thing today on my Silverado SS except it starts bad hot or cold-like cranking 6 to 10 seconds. Mine runs fine thou after it starts thats why I don't think its the fuel pump....Any answers would be great. Thanks

GM-Tech Senior Enthusiast

GM-Tech

Posted
Posted

I have to disagree with your buddy. The most common cause of this is the fuel pump. Actually, the check valve in the pump, but as that's internal to the pump, you have to replace the whole thing. I've seen the occasional regulator cause this, but not nearly as many regulators as fuel pumps.

 

It's easy enough to figure which it is. Block off the return line and if the pressure still drops, it can only be returning via the pressure line. In other words, it's the pump. If blocking the return line stops the pressure from bleeding off, it's the regulator.

 

On very rare occasions, you could have an injector that's leaking. In fact, we had a 4.3 that was doing that just the other day. The difference is that, after the long crank time, once it did start, it ran really rough because one cylinder was flooded. An injector leaking is very uncommon and this would be my very last choice.

s-cam Enthusiast

s-cam

Posted
Posted
I have to disagree with your buddy. The most common cause of this is the fuel pump.  Actually, the check valve in the pump, but as that's internal to the pump, you have to replace the whole thing.  I've seen the occasional regulator cause this, but not nearly as many regulators as fuel pumps.

 

It's easy enough to figure which it is.  Block off the return line and if the pressure still drops, it can only be returning via the pressure line.  In other words, it's the pump.  If blocking the return line stops the pressure from bleeding off, it's the regulator.

 

On very rare occasions, you could have an injector that's leaking.  In fact, we had a 4.3 that was doing that just the other day.  The difference is that, after the long crank time, once it did start, it ran really rough because one cylinder was flooded.  An injector leaking is very uncommon and this would be my very last choice.

 

 

 

I was just guessing as to why I never thought it is the fuel pump. I will check it out tonite on my truck and figure which one is the blame-thanks for the information its appreciated.

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