Slow starting

Reply Subscribe

Thread Tools

Search this Thread

Apr 26, 2011 | 10:53 AM

C5PEWTER/CONV

Thread Starter

Intermediate

Joined: Jul 2010

Posts: 30

Likes: 0

Slow starting

My 01 has suddenly begun starting slow, cranking for 10 seconds, it was running fine for awhile but now has started running a little ragged at start up but settles down if you rev the engine. It used to pop at the first turn of the key. Several people have suggested replacing the fuel pressure regulator as the first step. Fuel filter? It only has 29,000 miles.

Any thoughts or suggestions would be appreciated.

Apr 26, 2011 | 11:13 AM

lucky131969

Tech Contributor

Joined: Jan 2007

Posts: 19,470

Likes: 1,170

From: Dyer, IN

Quote:

Originally Posted by C5PEWTER/CONV

So it's not really slow "cranking", it just cranks for a while before firing? First thing to evaluate, is the fuel pressure/bleed down at the rail.

Apr 26, 2011 | 11:27 AM

C5PEWTER/CONV

Thread Starter

Intermediate

Joined: Jul 2010

Posts: 30

Likes: 0

Thanks for quick input. You are correct it cranks just fine. I'm not a mechanic so I want info to pass along to the shop guys so I am better informed and do not get ripped off. Exactly what is the fuel pressure bleed down.

Thanks Much

Apr 26, 2011 | 11:37 AM

lucky131969

Tech Contributor

Joined: Jan 2007

Posts: 19,470

Likes: 1,170

From: Dyer, IN

Quote:

Originally Posted by C5PEWTER/CONV

When you install a pressure gauge at the rail, you are looking for two things(turning key to on, pump will prime for 2 seconds):

1) Adequate pressure ~55-61 psi
2) Pressure should hold, and not drop off.

If the pressure drops immediately, if could be a leaky injector, check valve, or pressure regulator.

Apr 26, 2011 | 12:03 PM

C5PEWTER/CONV

Thread Starter

Intermediate

Joined: Jul 2010

Posts: 30

Likes: 0

Thanks again for the reply I will pass this along to he mechanic.

Apr 26, 2011 | 12:21 PM

Quicksilver Vert 01

Tech Contributor

Joined: May 2008

Posts: 3,100

Likes: 17

From: Somers, CT and Clermont, FL

St. Jude Donor '09-'10-'11-'12-'13-'14-'15-'16

The check valve that lucky mentioned, is often an integral part of the fuel pump.

I had the same long-cranking problem, which you described, on my old Silverado.
Replacing the fuel pump cured it.

Apr 26, 2011 | 01:00 PM

ricknyc23

Melting Slicks

Joined: Sep 2007

Posts: 2,599

Likes: 1

From: Long Island, Nassau County New York

I find most mechanics do not appreciate customer giving advice on what needs to be checked during troubleshooting.

Quote:

Originally Posted by C5PEWTER/CONV

Thanks again for the reply I will pass this along to he mechanic.

Apr 26, 2011 | 02:31 PM

toddk

Racer

Joined: Feb 2004

Posts: 359

Likes: 7

From: St. Paul MN

If the fuel pressure builds too slowly, it is also possible the fuel pump is going or the filter is clogged. My neighbor had this same issue with his Durango which would crank for a full 4 seconds before it would fire up. We confirmed with a pressure gauge on the fuel rail's schrader valve.

He was able to delay his trip to the shop over the long holiday weekend by doing a "double key" before cranking. Key in to run position (no crank), key out, wait a few seconds, key in to run, then crank to start. The fuel pump primes for 2 seconds when the key is first inserted. The second prime cycle boosted the pressure enough to start. This is a quick thing to check without needing any tools.

Unless it's a leaky injector, I agree with everyone else that you're likely in for a new fuel pump assembly.

Todd