Engine/Transmission (1998.5 - 2002) More Hard Start Issues.......

[smokinhole]

I've been following the other threads relating to hard starts after installing the GDP Walbro pump. I am in the same boat and I would like to know if anybody has found a solution for the problem.



I lost the original VP44 about two months ago and replaced it with a remanufactured pump from Midwest Injection. At the same time I replaced the lift pump with the GDP 392 system.



Since day one I had hard starting issues. I'm talking 20 seconds plus of cranking. I didn't know what was going on so I installed a fuel pressure gauge and as soon as that was installed, a miracle happened, my hard starts disappeared for a month. The truck started first turn every time. Then yesterday, they returned out of nowhere and worse than ever.



So, here's where I'm at. I have had the ECM reflashed with the update. Checked all fittings and bled the system. My fuel pressure is around 15lbs when running and I did take the shim out of the bypass to reduce the pressure to the VP44. One thing that I have noticed that is different is that it the pump does not run every time I turn the ignition on. It seems intermittent.



I'm starting to wonder if maybe I have a bad remanufactured VP44?



Please Help! I'm losing my sanity... ... .



BTW, The customer service from GDP has been first rate. Problem is nobody knows what the heck is going on with the truck. Everybody just looks at the thing and scratches their head.

 

[PRout]

Gee wiz, I thought all hard starts were caused by installing a FASS! It couldnt possibly happen with the "superior" Walbro pumps. . Could it??

Ok, sarcasm off. .

Have you tried interrupting the power to your pump while the starter is cranking yet? I had a hard start problem after installing the fass and it happened with an old VP44 and a brand new one (edited: reman pump). That was with about 15 psi of pressure like you have. I ended up adding a push button switch in line with the relay trigger. The switch was a normally-closed type so it opened the circuit when the button was pushed. It was a temporary solution to my hard start problem. Since then I changed the wiring so that the FP relay runs off the power window circuit. Its on all the time the key is on, except while starting. Has been several months now, and not one hard start since. You might want to try investigating that approach. . Hope that helps. . Good luck.

 

[smokinhole]

Shortshift,

I'll give it a shot and see what happens. I had heard of this before but, I was thinking it more of a lack of fuel issue or air in the system, rather than too much pressure. At this point in the game I'm up for anything! I just wonder why there is no singular "sure thing" fix for this problem? It seems that people are trying all kinds of different solutions with no really spectacular results that i've heard of. I'm tempted to just ditch the aftermarket system all together and go back to stock. it worked great for 160,000 miles! My attempt to make the fuel system bulletproof reliable has severely backfired on me.



Anybody have any info on a parts list to make this cutout relay? I'm electrically challenged sometimes.....

 

[PRout]

One quick way to tell if this will help is to remove the fuse to the pump, or the hot wire that powers the pump. Give it a start without the Walbro running and see how it starts. If it starts quick, then you might want to try it with the power connected, maybe go back and forth a couple times to be sure one way or the other. Just make sure you shut it off fast and dont let it run without the lift pump running.

If that doesnt make a difference then you may have a slight leak somewhere in the system causing a loss of prime.

Its a good next step to take in troubleshooting your problem.

 

[BTowler]

Is your hard start all the time? Mine is just hot, which the folks at Blue Chip tell me is a sign that the computer on the VP44 is going bad. If yours is all the time, try what Mr. Sarcastic :-laf (sorry SS, couldn't resist that one) said about the fuse, if that doesn't fix it, check all your pushlock fittings real well, I use those for the misting systems I build and have found that they don't like being pulled out of line at the fitting, this can cause it to leak or draw air (mine are holding city water pressure going into the pump, usually 50-100 psi, so that may have something to do with it as well, but they are supposed to be good to 250 psi).

 

[smokinhole]

Update.....



I tried disableing the pump and it didn't help the situation. So I figured I must have an air leak somewhere. Also read in another thread that teflon tape is not diesel resistant and that is what I used when I put the gauges on.



I took everything apart and used Rectorseal #5 on the fittings and as of now the problem is solved. Truck starts great hot or cold. So, it must have been a small air leak in one of the fittings. Hopefully this doesn't rear it's ugly head again.



So for now, all is good!



Thanks for all the advise, much appreciated.

 

[BTowler]

The teflon was your problem since all the fittings are an fittings, no sealant is required. The teflon was keeping the mating surfaces from contacting.

 

[smokinhole]

Thanks, I didn't know that. I figured they all needed taped.



I read your thread. Did you get your problems sorted out? I've noticed that there are alot of guys having similar issues as us.

 

[BTowler]

Nope, still living with it, haven't had time to pull the bypass valve and remove the spacers yet. I think the guys at Blue Chip are right, the computer on the VP44, I have done the fuse pull and it still hard starts, and it is only when it is hot, if the truck sits for 1 1/2 hours or more there is no hard start.

 

[NoSeeUm]

This is not exactly topic related, and my truck is an 2002, but here is the way my LP works. AFAIK I have the latest reflash via the Smarty. I know all this because with the pump hard mounted to the cab under body I can hear it very well.



As soon as the key goes to "ON" the LP will start and run for about 2 seconds then shut off.



"Wait to Start"



After the key goes back to "ON" from "Start" the LP will start again. If the engine is running it will stay on. If the engine is not running it will run for about 30 seconds and shut off.



Hope this helps some.

Jim