LB7 hard starting issues

[The Neens]

My '02 just started having trouble with normal temp restarts...It will start on the 1st try in the AM, but sometimes after driving, shutting down, and trying to restart a few minutes later, it will not fire until the 4-6 attempt...Fuel filter is good and keeping prime...I've tried to bleed the assembly, but it's no help...Balance rates look fine cold and warm on original injectors with 45,000 miles...Any ideas/suggestions?...Thanks

 

[02freighttrain]

Did this start all at once or did you notice the hard start get progressively worse?

 

[Mike L.]

Air in the system?

 

[The Neens]

Did this start all at once or did you notice the hard start get progressively worse?

It is getting progressively worse...There isn't any fuel in the oil and I haven't noticed any smoke out of the pipe while cranking...

Air in the system?

That's what we thought, but bleeding and pumping at the filter assembly doesn't seem to change things...With my limited knowledge of this, I've come up with (1) One or more injectors are not opening when trying to restart...(2) Fuel pressure regulator is acting funny...(3) Intermittent electrical/wiring issue...
Thanks guys...

 

[02freighttrain]

I don't want to point you in the wrong direction, but it sounds like air in the rails. I don't know, but you may have a siphon or bleed back out of the rails through the cp3. I know anytime you have any air in the system, a hard start is the first thing that happens. If your balance rates look good after start then my guess it's air. Have you ever had the system open? Seen any leaks around the ecm? If it's slowly getting worse it could/maybe be a lose fitting somewhere. Sorry, if I'm steering you wrong...........

Also sometimes pressure, as in running, will seal a leak and open it up when the pressure is gone. The balance tells a lot about injectors but can fool you as well. If it's under waranty (200K). Take it to the dealer....

 

[McRat]

Does it act any different if you leave the key in run position for several seconds before starting? Perhaps a glow plug or two is shot.

But like above, the most common things are air getting into the fuel system or a bad CP3 regulator.

 

[The Neens]

What's interesting is that it's done this 3 days in a row, but each morning it's fired up immediately when cold, so the fuel is there..Freighttrain, when it's acting up, I can just crank it several times for a few seconds each and it'll start after about 4, 5, or 6 times...This is without doing anything else, just cranking...Pat, I haven't tried leaving the key in the "on" position yet when trying a warm restart, but since you mentioned it, I have used my awesome EFI Live skills to disable the P0380 code we were getting about a month ago...What effect do the glow plugs have on the warm restart?

 

[LB7Diesel]

Chris when it starts acting up Cycle the key back to the off position then try cranking again. My truck get's this stupid little act in it sometimes and if I cycle the key back and forth it starts fine..WTF causes this, I don't know

Joey

 

[The Neens]

Chris when it starts acting up Cycle the key back to the off position then try cranking again. My truck get's this stupid little act in it sometimes and if I cycle the key back and forth it starts fine..WTF causes this, I don't know

Joey

Joey, I'll give it a shot...Thanks again for the help guys...

 

[Bluemax]

I had a problem a couple weeks ago that sounds just like this. I gave up and went to a dealer. They blamed it on my remote starter and reprogrammed the theft system. So far its started every time, So if all else fails you might look into it.

 

[The Neens]

It's headed to the dealer right now for a warranty-covered glow plug module replacement...I'll let you know what happens...

 

[LB7Diesel]

Ah-Hah, This could be my Prob also. By cycling my key switch, It's also cycling the Module....

 

[sweetdiesel]

Ah-Hah, This could be my Prob also. By cycling my key switch, It's also cycling the Module....

my old 6.2 diesel i had to do cycle the pugs 3-4 times before attemting to start

 

[The Neens]

my old 6.2 diesel i had to do cycle the pugs 3-4 times before attemting to start

How many CP3s did ya have on that one Simon? I should have an answer in the AM...

 

[The Neens]

Just picked up the '02...They replaced 1 pass side glow plug and took care of a P1631 theft deterrent code issue...So far it has had trouble restarting twice, but started on the 2nd try, no CEL yet...See what happens over the weekend...Thanks for all the responses...Chris

 

[sweetdiesel]

How many CP3s did ya have on that one Simon? I should have an answer in the AM...

it was the 95 6.5 turbo that one went through 9 pumps
3 months to a pump average

hope its all good now for ya chris

 

[sweetdiesel]

can we still test the glow plug with a test light?

 

[The Neens]

can we still test the glow plug with a test light?

IIRC, I read a post on the DP suggesting removing the wire going to it and check continuity to ground...

 

[The Neens]

I definitely have a problem with the theft deterrent...Wouldn't restart twice today, but after 2 cranking attempts, I hit "unlock" on the remote and it fired right up...This is after the service writer told me yesterday that they replaced the "theft deterrent module" in the steering column...Yeah, sure they did...