2003 LS V8 Cranks Too Long Before Starting

[TXLS]

My '03 LS V8 cranks longer than usual before the engine "catches". It spins over fine on the starter, so it's not a battery or starter problem. When I turn the key, it acts like an engine with the coil wire off, and then it catches and runs normally. It used to take no more than a "bump" to start the engine. Is this indicitave of a sensor (crank, cam, etc.) problem, or something else? Would like to know of a diagnostic that I can run, or someone's experience with a "known fix" before searching aimlessly. Any feedback is appreciated.

Cheers,

JD

 

[joegr]

It's probably not the crank sensor. If it were, it would set a code and you'd have a check engine light on. The three things that firs come to mind are:
1. Marginal COP(s) and/or plugs. How long ago did you change the coils and plugs? Ever have an misses under mild acceleration?
2. Leaky fuel injector(s). Do you ever get a puff of smoke after starting? Does it run ruff for a few seconds after starting?
3. Bad fuel pump (or check valve in the fuel pump assembly). If you turn the key to run for a couple of seconds, then off and back to run for a couple more seconds and then to start, does it start normally?

 

[LS4me]

My '03 LS V8 cranks longer than usual before the engine "catches". It spins over fine on the starter, so it's not a battery or starter problem. When I turn the key, it acts like an engine with the coil wire off, and then it catches and runs normally. It used to take no more than a "bump" to start the engine. Is this indicitave of a sensor (crank, cam, etc.) problem, or something else? Would like to know of a diagnostic that I can run, or someone's experience with a "known fix" before searching aimlessly. Any feedback is appreciated.

Cheers,

JD

Mine did that when I was using Costco gas. It started taking longer and longer to start. When I went back to Shell or Chevron the car began starting "normally". I would check your fuel quality first as that is the cheapest fix.

 

[TXLS]

It's probably not the crank sensor. If it were, it would set a code and you'd have a check engine light on. The three things that firs come to mind are:
1. Marginal COP(s) and/or plugs. How long ago did you change the coils and plugs? Ever have an misses under mild acceleration?
2. Leaky fuel injector(s). Do you ever get a puff of smoke after starting? Does it run ruff for a few seconds after starting?
3. Bad fuel pump (or check valve in the fuel pump assembly). If you turn the key to run for a couple of seconds, then off and back to run for a couple more seconds and then to start, does it start normally?

Thanks for your response. In response to your questions:

1. I replaced all the COP's and plugs about a year or year and a half ago. It did occasionally have the miss under mild acceleration, and several COP's were replaced under warranty back in the day. At 100-120K miles, I did the plugs and replaced all the COP's again. No miss issues since.
2. This is my wife's car, so I don't know about the puff of smoke but it doesn't seem to run rough upon starting.
3. I'll try bumping the key before starting this evening and see if that makes a difference.

I actually DO have a CEL that comes and goes. I need to pull the code and see what it says. I'll post back when I have the code. I'm actually chasing down a bunch of problems with this car which all more or less showed up at the same time. My problem is that I don't know which may be related to the others. I'm going to make separate posts for the other issues, but here is a run-down of what I'm fighting in case it jogs any ideas:

1. Aforementioned hard starting issue.
2. Hissing sound from under the dash when A/C is turned on, and no cooling through vents.
3. Before the A/C went to hot, there were different temperatures coming from the LH and RH side vents (hotter on the RH). I replaced the DCCV with a brand new Motorcraft valve, which made no difference. Pulled codes from the system last night and got 1242, 2798 and 2796.
4. LH power seat is inoperative. Blows fuse #7 the instant I plug a new one in. Even before the seat is moved.
5. Power mirrors are inoperative. I believe this will go away when I fix the power seat issue as they share a circuit.

Like I said, I'll be posting these issues seperately, but wanted to list everything here in case someone sees a connection. I appreciate your help.

JD

 

[RigsLS]

Don't forget the fuel filter

 

[TXLS]

Mine did that when I was using Costco gas. It started taking longer and longer to start. When I went back to Shell or Chevron the car began starting "normally". I would check your fuel quality first as that is the cheapest fix.

I'll check and see where my wife has been buying gas, and have her try a name brand station if she hasn't been using one. I DO know that we always buy premium fuel, so it's likely not related to using regular.

Thanks!

JD

 

[TXLS]

Don't forget the fuel filter

Good idea; I've never changed the fuel filter. I'll get into the service manual and find out where it's at.

Thanks,

JD

 

[jjcool00]

Driver side front wheel well

 

[RigsLS]

Good idea; I've never changed the fuel filter. I'll get into the service manual and find out where it's at.

Thanks,

JD

When i got to re&re mine, the forward flow was clear fuel but ...
when I held it backwards and let the fuel flow back the way it came in ... yikes, nothing but brown mud!

Ran ten times better since, improved fuel milage and quicker on the pedal. Filters get clogged over time.

 

[TXLS]

Great feedback guys; Thanks! I'll update with results after I get the filter changed.

JD

 

[epikls]

When i got to re&re mine, the forward flow was clear fuel but ...
when I held it backwards and let the fuel flow back the way it came in ... yikes, nothing but brown mud!

Ran ten times better since, improved fuel milage and quicker on the pedal. Filters get clogged over time.

When I changed mine black mud came out
And as bigrig said the engine ran way better
Increased mpg
and quicker pedal

 

[1LoudLS]

i changed my fuel filter when i first got it @65k, I was kinda freaking out about all the brown mud sh!t that came out of the filter!!!
at least it was doing its job.

 

[stugots]

Had the same problem on my 03. After new coils and plugs it still did it 10% of the time. Cleaned my maf and tb, hasn't done it since. That was a few months ago. Not really sure how, or if it was related.

 

[TXLS]

I installed a new fuel filter last night. Didn't get finished until late, so I'll road test it tonight before I dig back into my climate control issue. After removing the original, I blew it out; shot clear out one end, and pretty brown out the other. Not a great quantity, but I could tell it was dirty and ready for replacement. I'm going to blast the MAF and TB tonight as another step just to be sure. I'll report back after I give it a cold-start and road test.

Thanks!

JD

 

[TXLS]

I installed a new fuel filter last night. Didn't get finished until late, so I'll road test it tonight before I dig back into my climate control issue. After removing the original, I blew it out; shot clear out one end, and pretty brown out the other. Not a great quantity, but I could tell it was dirty and ready for replacement. I'm going to blast the MAF and TB tonight as another step just to be sure. I'll report back after I give it a cold-start and road test.

Thanks!

JD

The new filter certainly seemed to help. Thanks for everyone's input!

JD

 

[RigsLS]