Left home this morning everything was going good. About 6 miles into my trip my truck stumbled real bad but recovered and this was while acellerating right around 1800 rpm. I kept on my journy and it progressivly got worse. Smoke egts, boost, fuel pressure were all normal. Once I arrived at my buddys house it would do it at idle, it never stalls. I chect the FSS wire it was a little loose so I crimped it down and cleaned it up but same results running. I've got a clear hose running to the fuel pressure gauge and I never saw any bubbles in there. I think its the FSS but I'm looking for more ideas. And sorry if the spelling is FUBAR I'm on my HTC. Thanks in Advance.

Check for fuel in the fuel. Maybe the lp is bad and pumping air into the fuel.

Are you leaking any fuel around the IP?

Maybe some bad wiring to the fss. Try hot wiring it. It sounds electrical or air in the fuel. Does it still shut down with the key like normal? Does it act differently hot or cold?

Check for fuel in the fuel. Maybe the lp is bad and pumping air into the fuel.

I hope he has fuel in the fuel.[dummy][duhhh][laugh]

Water in the fuel would be bad though........

Are you leaking any fuel around the IP?

NOPE, LEAK FREE BESIDES THE STEERING GEAR.

Maybe some bad wiring to the fss. Try hot wiring it. It sounds electrical or air in the fuel. Does it still shut down with the key like normal? Does it act differently hot or cold?

SHUTS DOWN JUST FINE, HOT OR COLD IT DOES IT. I WAS PLANNING ON A HOT WIRE. Í'M REALLY HOPING THAT IT'S JUST AN IGNITION SWITCH.

I hope he has fuel in the fuel.[dummy][duhhh][laugh]

Water in the fuel would be bad though........

oil in the fuel is what I meant.[duhhh] You guys know what I meant!!!!! Thats what I get for posting from my phone it is a pain.[duhhh]

oil in the fuel is what I meant.[duhhh] You guys know what I meant!!!!! Thats what I get for posting from my phone it is a pain.[duhhh]

Even so, with oil in the fuel, it'd still run. Oil will burn with the fuel and if there's enough it'll be a blue-ish color smoke. Is it even possible to get oil in the fuel other than dumping a quart of ATF or 2-cycle oil in the tank when fueling?

I'd assume air in the system somewhere. Bleed the lines wherever you can for starters if you haven't already.

I still said it backwards fuel in the oil. Its been one of those days.

I still said it backwards fuel in the oil. Its been one of those days.

[laugh][laugh]

We've all had them. I assumed that's what you meant though but didn't correct you.

I'd throw a fuel filter at it.

I'd throw a fuel filter at it.

fleet gaurd 1000 less than a month old and only 4 psi drop across. I'm finaly on my way to the truck, I'll have more info in the next couple of hours.

Ok made it home. If I keep the tach above 2k then it's fine. It will "catipiller" when it acts up at Idle but still hasn't stalled on me...yet it get real close this thing sound kinda cool at 4OO rpms...lol
I applied another 12 volts to the FSS and it still did the same thing. I then left that leg on and took away the igniton feed with the same results. No fuel in the oil and the fuel pressure never drops on either side of the fuel filter. I have yet to find a peice of .5 clear hose to see if I'm getting air in the fuel....but my redneck thinking has me believing that if I had enough air to make this truck run like this then I'd see a drop in fuel pressure.. But I will get a peice of clear hose to check it out. The only other thing is that I may have pressure and not any volume, like the in tank filter/screen has plugged up...but that was all cleaned out about 5-8 thousand miles ago when I droped the tank to upgrade to the .5 supply hoses.
Is there anything inside of the High Pressure pump that can cause what the problems I'm having. I have a spare pump that I can throw on but I'm not realy wanting to do that in 110* heat if I'm not sure it will fix it. OH and the cold water over the High Pressure pump does nothing, and there is no rime or reason to the timing of when the "stumble" occures. It will be just fine for 1 minute of Idle time then it will drop out and go for 30 seconds then It may take 3 minutes to do it, so Its not rhythmic as to when it occurs. Sorry for the novel just trying to give info for the brains to come up with ideas...cause mine is not working

Water in fuel maybe? Every time it idles weird maybe that's water getting pushed through it? I live here in AZ too and I never ever get water in my fuel but its possible. FSS seems like its not the the problem. If it was trying to close while driving it would have shredded by now. When it does this does it get really rough or does the idle just drop super low. 400 will feel rough of coarse but do you think all 6 injectors are still firing? If so it could be a governor issue thats allowing it to drop rpm way too low. Sounds odd, but I had a similar issue with my 14mm pump. Idled so low it died and would not start even though they are at full fuel when they first crank over. It had no hint of fire. Couple minutes later it fired right up but idled at 1100 rpm when it was set to 800ish.

No water in fuel. And it does seem that there is no miss to it, it just starts to go way low. We call it "catipillering" at Genermal Motors so that's what I'm going to call it. But it is hard to tell with that low of an Idle. So what needs to be done about the govenor? Is there any tests for it or just a your are screwed. The furthest I've been into these pumps is for the 366, But I'm not scared so.......?

I pulled the top off of mine and inspected the governor and could see nothing wrong with it. Given the amount of $$ I sank into the stupid thing I decided to just pull it off and send it back to Giles and let him look at it for me. I have decided the 14mm is not a good street machine for me. When he fixes it, it will go on the shelf until its time to play. Meantime I am running my stock pump, which is on its last legs[verymad]l, until my new 12mm is done.

Ok, sound like we need to have a pump R&R party. So you won't have the big giles 14mm pump at the dyno on the 14th? That sucks I really wanted to see your truck run all of that fuel. So at what point should I say screw it and go Pee Pump. I guess my question is how much do you have in the Giles? My new plan is to put my rebuilt stock 12mm on and was thinking of sending out the FUBARed one out to be turned into a go fast pump, but I need to figure out the jumping off point...I'd really like to stay VE but there is a glass roof.
What is your meaning of the Giles is too much for the street? Fuel economy, smoke, egt.....?

Ok NO AIR IN THE FUEL!!! And I made sure there were no blockages. So to recap good fuel, good fuel supply, FSS operates with jumped 12Volts and on ignition 12Volts. So before I go and rip this truck apart again to slide another one of my pumps in have I overlooked something some where? I've done some reading on the operation of this pump and as SOOT4BRAINS said it sounds like the govenor is sticking and could cause this problem. But then again there maybe something else that is simple that I'm looking/thinking to hard and over shooting a simple answer. I'm willing to try it all before condeming this pump.
Thanks for all of your guys support threw this......I'll have to get you guys a round. Just tell the bar keep that your buddy is coming by in a few and it's on him....LOL

The only other suggestion I have is maybe pull the fss and gut it. Maybe the seloniod is getting weak and partially blocking fuel. May not be the problem but it is just a thought.

Yhea I was thinking of doing it...But it always lights with half a turn of the engine and it shuts down right away. But I did ask for suggestions now didn't I, so let me go out and give it a try.......I'll BE BACK

lol it cant hurt before you spend a lot of money on a new pump lol.

Well as much as I hoped that you were right....Nope. Still the same thing, on a side note I had a "here's your sign" moment. I shut the key off and was like what the .... the truck is still running. It's been a while without sleep, that's my story and I'm sticking to it. The funniest thing is my other truck has a pull cable and well I've got my sign for the night...LOL
Looks like sunday will be pump R&R day.

I can't think of any other issues that could cause that except internal pump issues. The 14mm giles was ok for street use but not for me. I put too many miles on it to have it on there all the time. I'm not sure how to describe this, but it runs rough. I really didn't notice it until I put my 12mm back on and was surprised how smooth it ran. It doesn't feel rough like a misfire or timing to far off, just overall rough. It has a bit much timing for daily driving and it comes on too fast with the high case pressure. But when you nail it below 50mph it burns rubber and plants you in the seat. It got the same mileage as my 12mm and it smoked less down low. The most smoke was at full throttle because my little 62mm turbo is no where near enough air for it. It has a very tight afc on it and 66% of its fuel is controlled by the afc. Very awesome pump tuning. I too was looking forward to throwing it on the rollers, but not this time. On the other hand Giles just finished my tuned 12mm pump. Same afc setup as 14mm but is 12mm so its reliable. Stock case pressure but added 4mm of movement to the timing piston. It benched 250 cc's at 2000 rpm and maintains over 200 till it hits the governor. It should still throw down some decent numbers on dyno day. I may even have a new turbo on by then. As far as Giles prices shoot me a pm, I promised him I wouldn't put it out on the forums.

Sorry it didn't work.

Sorry it didn't work.

Don't be sorry. I wish it would have but OH WELL. When people ask why I keep fixing "that old smoking truck" I say No truck payment and it has yet to leave me on the side of the road. Even with this hickup it still got me home. I will keep fixing it as opposed to a 600$ truck payment a month and no where near the fuel milage that I get.

Don't be sorry. I wish it would have but OH WELL. When people ask why I keep fixing "that old smoking truck" I say No truck payment and it has yet to leave me on the side of the road. Even with this hickup it still got me home. I will keep fixing it as opposed to a 600$ truck payment a month and no where near the fuel milage that I get.

I know what you mean about being paid for. My buddy has a beautiful megacab dually with a 700 a month payment. It is a nice truck but that is a crazy amount of money. I have put about 4,000 in my truck in the last 6 months or so but alot of that was stuff I wanted to do not needed to do. Even if I had a new truck there would still be stuff I wanted to do to make it the way I wanted it. So then I would have a payment and still would be looking for money for mods lol...

Ok guys got the new pump on and it is .....fixed. Put about 30 miles on it with my phone in hand..just in case!
I set the timming to 2.0mm and it seems I've lost a little top end. The thing is that my old pump was timmed at 1.9mm. I'm tired of looking at the engine so I'm going to run it for now...
Oh and Now I find out that my frame is broke as all hell and I'm going to have to pull off the front clip to fisher plate it and build back up the frame... But I'll still fix it...LOL I guess it's time to lift it a little so I can put cross over steering on it. Any one running hydro assist with there cross over. I have just cross over on the crew and love it, but thinking of hydro assist to keep the stress on the frame down. Need opnions thanks