Engine surges & then almost stalls.

[DWestfall]

Today I horsed around a little bit with the xzilliraider set on 100 HP. I turned it back to 0 & ran some errands. I pulled it out of gear and the truck surged and then wanted to stall. Ran real rough in Drive at idle. It did this a few times before I installed the Quad Box so Im thinking it cant be that. But it seems worse now. Whenever I have it in park for a minute or two and then put it in Drive it did this. Surge and then stumble. I just shut the truck off and I will see if it does it after it is cooled down. Is the transmission wanting to lock up? Should I worry? No codes as well.

 

[qzilla]

If you don't have any DTC's then it may be tough to find the problem. I have had a harness that was surging, but at highway speeds. Once we diagnosed it we replaced the harness and all wasa well. When we inspected the harness we found that one wire had some extra resistance and it was obviously causing the problem.



This just does not sound like the same situation. If you keep having the problem you need to call us. We can walk you through some test steps to make sure we are working properly.



Does the engine sound like it rattles when it tries to stall, or does it just sound like it is being pulled down?



Whatever it is we can help you figure it out.



Quad

 

[SRadke]

Do you get any white smoke during this surge/stumble?



-Scott

 

[RustyJC]

I had a friend with a 2003 HO/48RE that did this. It turned out to be a bad pressure sensor for the HP fuel rail. IIRC, at the time his was repaired, they had to change out the HP fuel pump as the sensor was a part of the pump assembly and not replaceable in the field.



Rusty

 

[DWestfall]

Yes, it does rattle when it does surge. Then it seems as if it is being pulled down. No, I dont think it produces white smoke. I will drive it again here shortly and post if it continues. Thanks for the info.

 

[bpenrod]

Sounds like what mine used to do until I found out the rail pressure sensor plug was not connected all the way, I think it is in there somewhere!

 

[jelag]

My 04 had this problem..... it started around 80K and was close to 90K when I took it in for service... . it turned out to be a failing lift pump that was doing damage to the injection pump... and it was injection pump failure... .



Poor idle... . would stumble as it came back to an idle and wanted to die... . and would stumble on acceleration.....



Hope this helps... ...



Jim

 

[MYamamoto]

I have been running in to basically the same problem that you are having. Every so often the truck with just drop to just about a stall then when it recovers it would rev up quite high, maybe around 2500 rpm. Other times, when the truck it idling, it would get a really bad clanking sound similar to the old 12 valve motors but louder and very unstable sounding. When I took it in to have it checked out, they could not find anything wrong but the motor also would not act up for them at all. One day I finally got it to act up and they narrowed it down to the pressure sensor on the injection pump. So they ended up having to order me a whole new injection pump to fix the problem. I just got the truck back yesterday afternoon, so I will just have to run it now and see how it does.

Before the problem was diagnosed, I said we were having problems getting the motor to act up. I had borrowed a PDQ box from a friend and anytime that box was turned on, the motor would act up and make the clanking sounds and stall quite a bit. When the box was off, it was pretty much back to normal and would not act up. Just have to be careful with that, if you take it to a dealer with a box on it, they might get a little fussy and blame it on the box.

Hope this info help out.

Mark

 

[jelag]

Mark.....



Go back to them and have them check the lift pump... Thats the same failure I had and was told it was from a bad lift pump... the the lack of fuel damaged the pressure senor and return fuel circuit in the pump..... lack of fuel galled the parts. . which would cause them to stick and act up... . Made lots of sense to me once they explained it to me... .



Jim

 

[DWestfall]

Mark.....



Go back to them and have them check the lift pump... Thats the same failure I had and was told it was from a bad lift pump... the the lack of fuel damaged the pressure senor and return fuel circuit in the pump..... lack of fuel galled the parts. . which would cause them to stick and act up... . Made lots of sense to me once they explained it to me... .





Well after a few days of driving and no 100HP runs it hasnt done it. I have had it on the 30HP setting but nothing. I wonder if after hammering it at the 100HP mark it is bringing the fuel pressure to 0 and getting things a little messed up. Would a high flow pump like from DPP cure this (the one that comes with the FASS system). Or is it the CP3 injection pump that is the culprit?

 

[MYamamoto]

Thanks Jim,

I just as this problem popped up, I installed an AirDog fuel pump system. I did not have a fuel pressure gauge on my truck before this pump but, from what I have been hearing the factory lift pumps do have problem, although not as many as the older 24 valve truck lift pumps. I kinda wish I had installed the fuel pressure gauge before the aftermarket pump just to see what was going on.

I do a lot of towing up some very steep hills around here. If my fuel pressure was dropping off and like you said damaging parts in the injection pump, that would have been a really useful piece of information.

Now that I have installed the AirDog pump system, I have been holding the fuel pressure around 12psi pulling the hills and 14 when sitting at idle. Hopefully this pump will help eliminate any further problems with my injection pump. Dont really want to have to pay for one of those things!!!!

 

[JThiessen]

Yesterday I made a 1100 mile trip from WA to eastern MT, and early on I noticed that when I turned on my cruise control, I would get a surge. The RPMs stayed constant, but my booost was bouncing about 3-4 lbs. It would do this with the Xz on levels 2,3, and 4. On 1 (or off), I thought I could hear a little surge, but it wasnt noticable on the boost guage. Could this be the same issue? I have NOT rechecked my connectors yet, but I'll be doing that today, as tomorrow we have a little 300 mile jaunt for haircuts. I think it was surging at idle in the morning before we left, but I was a little groggy standing out there waiting for hte ladies to load up.

 

[JStieger]

JThiesen-



When I was running the Bully Dog Power Pup a few weeks ago I noticed the same thing and chalked it up to the box at first. I did a fuel filter change and the boost surge disappeared. I gained about 1-2 psi on the fuel pressure also. The fuel filter only had 12,000 miles on it and looked OK. Hope this helps!

 

[JThiessen]

I might try that also. I just changed mine back in November (@8K miles) - but I have run winter blend through it since then. If it is plugged up, that might explain why it seems that my mileage has been down for a while.