Engine/Transmission (1998.5 - 2002) Hard starting sometimes...

[TSRAM]

I have on several occasions had trouble starting the truck. I normally wait for the grid heaters to cycle even in the summer even though I know she'll bust right off without them. On two occasions this week I've not let the grid heater cycle and attempted to start right away. The truck started and ran just a few revolutions and died. Upon trying to re-start and even letting the heaters cycle again, it takes several tries and running the starter almost excessively to get her going.

I've got 20lbs of fuel pressure at idle post filter and short block with only 2500 miles on it, not using oil, nor any blowby. What am I missing? I know I've started this truck a hundred times without doing a full heater cycle?

 

[DieselMinded]

WOW you sure are BOMBED !!!

Congrats.



Anyway



if you have 20 psi fuel and the motor is still acting like that I would say its your injectors because its still acting like a fueling problem.



Your getting 20psi from a fatory LP and a carter ??



Just my . 02



DM

 

[TSRAM]

Yes, 20 psi at idle and around 18 at cruise. I am beginning to wonder if maybe I have an air leak in the fuel line. I just recently re-installed my pusher pump after the "53" episode. I had a new lift pump installed in Dec. and just put the pusher back on about a month ago. No problems until last week though.

 

[AKAMAC]

Hard starting can be caused by excessive fuel pressure at cranking.



Does the pusher run in conjunction with the LP or is it controlled separately?



Mike

 

[BillGotthelf]

I would believe your vp44 is dieing. I had the same problem. It was like there was air in the lines with some starts. The fuel was leaking past the pistons (not all of them)in the VP44 causing low pressure and hard starts. The couple of cylinders that are getting correct fuel pressure have to drag the others till fuel pressure comes up enought to pop open the injectors.

 

[JJ Jackson]

TSRAM, are you're EGT's, boost and power down as well. I had the hard starts after I installed a FASS, followed by a slight loss of power and EGT's. I guess my old VP couldn't handle the pressure..... Good luck, Jim

 

[EBozard]

I will throw in my two cents. I had the same problem. I found out that my gasket on the fuel filter was put on wrong. It was catching air. I fixed that, then 4 months later it started happening again. I thought many thoughts, asked around and got many good suggestions. Then a week ago it was idling and smelt diesel. So i got looking under the hood very close for a long time. The return line from the IP had a very small drop of fuel. I cleaned it and about a minute later the drop appeared agian. AHHAAAAA! As the days past the starting has got harded and the drop is now a skeet and mist. Almost impossible to start, i got a new line this past thursday to put on today. Just my little experince, hope it helps, cya !

 

[TSRAM]

All the power is still there, though I don't run her as hard lately. I am also thinking air at the fuel filter. I changed the filter the same evening I put the pusher back in, but haven't had time to do much troubleshooting. It's only happened twice in almost a month since. But, both of those times were about 3 days apart.

 

[SKneeland]

same problem here, it went away for a month or so, just in the last couple weeks been having the same extended cranking issues. not every time though... once its running its fine, put the box on 5X5 and drive the crap out of it , no codes & cant bring the fuel pressure down to 5psi. leave it sit for more than 20 min. and it takes a 10sec crank to fire it up. no leaks, both fuel pumps working like they are supposed to.

 

[dalexander]

I have been having the same problem started with a dead lift pump, dealer replaced it. It worked fine for a couple weeks then it happened again. Took it back to dealer they replaced the IP and the LP again. Now starting to happen again after 3 weeks. Do not think it can be the LP or IP since both are brand new and pressures are fine. One thing I can add is that if I drive the truck to work 17 miles one way the problem does not manifest itself. If my wife drives it to work 4 miles one way it will be hard to start within a week. I am going to replace the fuel filter this week since it's a simple fix but I have doubts that this will fix it since I tried that last time. Fuel leak? Maybe I have smelled fuel from time to time. But why would it happen only when my wife drives it on short trips to work and back? Maybe longer trips purges out air in fuel lines? any ideas?



Thanks, Dennis

 

[TSRAM]

I had noticed this afternoon that my fuel press sending unit has a slight weep and my rubber fuel hose at the pusher pump has a few cracks in it. I will address those issues this week and see if it has any effect.

BTW, I have had the wait to start light not come on at all several times lately. I guess for some reason the grid heater is not cycling like it should either.

 

[dalexander]

Have not changed to filter yet had to work today. But I did try something, the last 3 days I parked my truck with the frontend downhill in the driveway. It started right up no problem. Came home from work my wife had truck parked uphill got into it to back it in(she's too nervous backing it in) and it would not start up again. The slope in the driveway is not that steep but evidently enough to cause some issue. The fuel must be draining back to tank or something when parked uphill. So any ideas? Could a slight leak allow enough air into the system to cause fuel to drain back to tank?



Thanks, Dennis

 

[WShupe]

I've been having the same sort of problem, but worse. Found two things actually. The first one was the injector lines were a little loose. The second one was the line on the back of the cylinder that you can't really see. It juctions into the line that comes off the vp44 and runs back to the tank. Well it was loose, and I mean ready for the banjo to come out. Found it while removing the head to get o-ringed. Thought you could check it, because mine did the same thing when you would park it on different inclines.

 

[BStowe]

I havent done much work on my DC yet but one thing we used to do with the older GM diesels to check for air in the fuel is to temporarily replace a small section of a return line with a piece of clear tubing. If there is any air getting into the system it will manifest itself as bubbles in the line. Not even sure if this is feasible with the Cummins.



You can also check for small leaks by pressurizing the fuel system from the engine back toward the tank and watch for fuel from the lines.

 

[TSRAM]

I knew the fuel press. sender for the fuel gauge was leaking fuel. I changed it yesterday midday. The truck started right up after sitting all afternoon and night. I have had problems since my last post of the hard starting after sitting anytime more than about an hour.