Another Surging Problem

Street sleeper

Part-Time Puller!!
Joined
Feb 10, 2009
Messages
411
My buddy just bought a 2001 5 speed truck. It has the following ungrades: S300 58mm from Schieds, 100hp injectors from Schieds, Schied's HO VP44 pump, Edge attitude with the hot setting, AFE intake, ATS exhaust manifold, and 5' stacks. He bought the truck with the chip unhooked, which it had plenty of power for him. At highway speeds if you kept your foot steady on the throttle, the rpms and truck feels like it is pulsating or surging about 300 rpms. He wanted me to try and fix it so I did the easy resetting the apps, but that didn't help. I wanted to know what this thing had in it so I hooked the chip back up and this thing can really haul the mail! It also surges more too.
So I think I will try checking the voltage on the apps, unless you guys think of something else. What do you think of "shimming the cam sensor" as another guy told me to do? Or is it the nature of the beast with all the mods done to this truck?
Thanks in advance!
 
What do you think about the truck having an SO ECM with a HO pump? Could this cause these problems?
 
Shim the Cam sensor? That is a new one for me...

This surging you describe, is it at a certain rpm/mph or does it happen randomly?
 
It happens mainly around 1200-2000 rpm with steady pedal position. It may happen at higher rpms than that but I haven't ran it with steady pedal at that speed. Some days are worse than others.
 
My truck is stock but I have this problem as well although not constantly. I will be checking the voltage on the APPS soon but it is annoying as hell.
 
I adjusted the voltage of the apps and that cured 75% of the annoying surge it had. I think the rest is the nature of the beast!
 
I've fought that dang problem for over two years now. What is the AIT temp when it happens? My truck will surge like that when AIT temp is less than around 100F and outside air temp is less than 70F. I've got a brand new ECM, reflashes, new AIT sensor, new MAP sensor, and checked everything under the sun from APPS to what every the heck else there is under the hood. I think it is the nature of the beast given your mods. Had the Edge checked-twice and it does it with no box.

I have II PS62/65/14 and DDP 110's. The truck idles great and pulls great at WOT but half throttle when it is cold is bad. Add a trailer and load it becomes horrible.

I have yet to try an adjustable pot on the AIT sensor wire to fool the engine intake temp (I've heard that works), but I'd really like to find a cure not a bandaid. Search my username and you'll find some threads on my troubles.
 
I think that adjusting the apps voltage just moves the apps to a different possition, helping cure the problem, not solving it.

I have done all of this, the only thing that cured it was a new apps., ( timbo ), very well priced btw.

you have the J/A on this thing, try watching the tps, it should be smooth, no jumps, not even small ones.
 
I have II PS62/65/14 and DDP 110's. The truck idles great and pulls great at WOT but half throttle when it is cold is bad. Add a trailer and load it becomes horrible.


I never had this problem with my truck until I was hauling a small Uhaul trailer with a couch and recliner in it in a snow storm. It was annoying as hell and I haven't had the problem since. I guess it could have been the TC locking and unlocking but man it was pissing me off.
 
I never had this problem with my truck until I was hauling a small Uhaul trailer with a couch and recliner in it in a snow storm. It was annoying as hell and I haven't had the problem since. I guess it could have been the TC locking and unlocking but man it was pissing me off.

Yes sir, it is a HUGE PITA when hauling a trailer or a payload. Even my welder rig (about 600 lbs) in the bed is horrible. It is managable bobtail, but still annoying for dumping so much money into the truck to have it do this. Back to my motto, "once you step into the 'performance' world, you have no idea what each truck will do, they will all act differenty."

I love winter because it doesn't smoke very bad. But I also love warmer weather so I don't have to deal with this.
 
mines doin the same thing but iv noticed its usually under low boost conditions (flat road steady rpm) then the intake gasket blow out and just made it worse! So one of these days im gonna try a boost fooler plug in thing to see if it helps. does anybody know if a man could put a resistor in the MAP wiring that would fool the ecm? what resistance does it need to see? same question for the IAT?
 
mine spits and sputters at very light throttle kinda like a hotrod pump sounds at idle, only started after i put a new inj pump on that was supposed to be stock so i dont know what to to do for mine
 
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