over rev problem
#1
over rev problem
alright, so when i get my truck goin at about 2200-2500 rpm and go to shift i let off the throttle and hit the clutch. the only problem is that my rpm's continue to build and i cant put the truck into the next gear until the rpms drop a bunch, happends all the way threw the pattern. could anyone give me some help with this.
#2
Cummins Guru
Does this happen with the cruise control switch on or off? There is a recall for ECM reflash if needed, maybe related if it applies to your truck. Read the recall to make sure if it does.
#3
alright, so when i get my truck goin at about 2200-2500 rpm and go to shift i let off the throttle and hit the clutch. the only problem is that my rpm's continue to build and i cant put the truck into the next gear until the rpms drop a bunch, happends all the way threw the pattern. could anyone give me some help with this.
Have tried it with the Quad off?
#5
#6
I'm stock but my truck ALWAYS drops RPM's normally no matter how I drive it.
I've heard many guys say it a CR thing but I don't buy it. It may be normal for a CR with a programmer to do it, but I don't think it's a normal condition for a stock rig to "hang" just because you're pressin' hard on the skinny pedal.
I've heard many guys say it a CR thing but I don't buy it. It may be normal for a CR with a programmer to do it, but I don't think it's a normal condition for a stock rig to "hang" just because you're pressin' hard on the skinny pedal.
#7
I'm stock but my truck ALWAYS drops RPM's normally no matter how I drive it.
I've heard many guys say it a CR thing but I don't buy it. It may be normal for a CR with a programmer to do it, but I don't think it's a normal condition for a stock rig to "hang" just because you're pressin' hard on the skinny pedal.
I've heard many guys say it a CR thing but I don't buy it. It may be normal for a CR with a programmer to do it, but I don't think it's a normal condition for a stock rig to "hang" just because you're pressin' hard on the skinny pedal.
That being said, if your truck doesn't do it and thousands of others do where is the difference? What supply fuel pressure do you have? What rail pressure are you running at 2600 rpm's under acceleration? How soon does that rail pressure drop when you lift off the accelerator?
I would hazard a guess yours is not normal from all reports but maybe you have a special tune that addresses it.
Trending Topics
#8
Its not from pressing hard on the skinny pedal, its from building high rail pressure and dumping the load quickly. Its normal with or without a programmer. Programmer just exagerates it with more fuel.
That being said, if your truck doesn't do it and thousands of others do where is the difference? What supply fuel pressure do you have? What rail pressure are you running at 2600 rpm's under acceleration? How soon does that rail pressure drop when you lift off the accelerator?
I would hazard a guess yours is not normal from all reports but maybe you have a special tune that addresses it.
That being said, if your truck doesn't do it and thousands of others do where is the difference? What supply fuel pressure do you have? What rail pressure are you running at 2600 rpm's under acceleration? How soon does that rail pressure drop when you lift off the accelerator?
I would hazard a guess yours is not normal from all reports but maybe you have a special tune that addresses it.
I'll say it one more time, I'M STOCK completely. I have no idea what fuel pressures are. All I know is I can run the truck clear up to redline and let off as fast as I'd like and the R's drop like normal not "hang" as the op is describing...
You can say what you want but I don't feel it's normal for a stock rig to "hang" like that.
I'm not a pro and don't have all of the answers but I've driven more than one Cummins diesel and have never had one "hang" at high rpm's....just my experience....
#9
Registered User
Auto's will do it too if you get into the right circumstances. Say, starting off in traffic real quick and having to stop quickly because someone is an idiot.
#10
Yes this is a normal side effect of the common rails. Especially in the earier ones. They will "hover" a bit before beginning to decelerate. Every single one ive driven has acted the same. 04.5 and up are not as bad but all are noticeable. If its hovering alot more than normal and causing to many rpms to shift within a reasonable time then I would say you have an issue. apps,throttle cable, could be the culprit. Floor mats seem to be pretty good at causing this aswell.
#11
I don't even notice it anymore as have learned to drive around it and compensate.
I do know every 3rd I have driven has done it to a certain degree, and, every 1st or 2nd gen that did it had a problem or they did not hang. The first time I whacked the throttle too hard in a parking lot I thought it was BROKE!
#12
So are you saying the injectors are still injecting more fuel than they should be after you've let off the accelerator pedal because of high rail pressure?
#13
If there wasn't a ramp down you would see spikes a LOT higher than they occur now and even faster injector failures.
#15
Yep, we call them electronic controlled but it is far from that easy. The ECU "thinks" much faster than any controls can operate. Built in time lag for translation is a big problem, both for OEM and aftermarket.