Light Throttle Hiccup

[mxaaron]

Has anyone experienced this symptom.



Light throttle, say travelling down the freeway at cruising speed. If you roll off of the throttle, say for a car merging on in front of you, then resume throttle lightly as they come up to speed. As I roll into the throttle lightly, I often get a rather abrupt hiccup. It doesn't have to happen on the freeway, it does it around town too. Always at light throttle loads. I can't tell if its during a passive regen or not.



Anyway, I never had this issue until I got re-flashed for the J35. I have 17300 miles, and have never had a check engine light, never had an active regeneration, in fact I've never had a problem with the truck what so ever.



It seems to be getting more and more frequent, and it's driving my batty.



My truck is a six speed manual, so I know it's not the trans shifting.



Any ideas?

 

[SNGLESHOT]

Apparently this is quite a common problem from looking at all the posts. My truck does the same almost exclusively during starting out or 'feathering the throttle' lightly etc. I used to think it was cause I was runnning with the exhaust brake on all the time etc... but now I wonder. I am up to date on flashes and not sure if the J35 had anything to do with this or not? Just cant remember. Must be getting old.

 

[RVTRKN]

Has anyone experienced this symptom.



Light throttle, say travelling down the freeway at cruising speed. If you roll off of the throttle, say for a car merging on in front of you, then resume throttle lightly as they come up to speed. As I roll into the throttle lightly, I often get a rather abrupt hiccup. It doesn't have to happen on the freeway, it does it around town too. Always at light throttle loads. I can't tell if its during a passive regen or not.



Anyway, I never had this issue until I got re-flashed for the J35. I have 17300 miles, and have never had a check engine light, never had an active regeneration, in fact I've never had a problem with the truck what so ever.



It seems to be getting more and more frequent, and it's driving my batty.



My truck is a six speed manual, so I know it's not the trans shifting.



Any ideas?

My 07 C&C was flashed in 09 (shouldn't have done it) and ever since then just before regen it will stumble. But it only happens once, then I have an odd shifting issue until regen is over. How I know when it is in regen? When shifting at my normal RPM (23-2500) it will take off like a bat out of hell once it reaches 2000 RPM, and the throttle seems to stick for a second, and the EB will engage at idle until regen is done. I dread the regen, because in the city I have to drive slow to prevent this phenomenon. I also have a lack of power below 2000 RPM.



It is my fault because I was given the choice of the flash and was warned there is no way of knowing what the difference will be. When this phenomenon first happened, my tech and I agreed it could be the throttle position sensor failing so it was replaced under warranty. When it stumbled again, I immediately took to my tech and went on a road test with my trany tech and the tech that handled the flash, and confirmed with the computer hooked up to it on the road test that it was in regen. It did the phenomenon for the trany tech that was driving, and he was amazed of the instant power takeoff after 2000 RPM. Also if I'm cruising at highway speeds and lightly press on the throttle, it will not respond for what seems like an eternity, but is actually a few seconds, that will tell me my regen has started.



I've learned to live with it, but I'm not happy about it. last year it was reflashed for the latest update and seems to have gotten rid of the stumble but it stills has the shifting phenomenon.

 

[mxaaron]

Mine too has the regen "Turbo boost!" My wife drove the truck the other day and asked me, "Why does it feel sluggish some times and other times feels like its going to burn the tires off?"



If she can notice it, it must be noticeable!



Anyway, I had a feeling it might be associated with the regen, as I typically feel it when the truck has that lag followed by a boosted acceleration.



My truck too was perfect (in my opinion) before the J35. I have never had a regen notification, never had an oil change indicator either. The only thing I am upset by though is that the truck runs entirely different after this flash. Not really the truck I test drove and bought. That's the disappointment to me.

 

[RVTRKN]

And to think I had a choice. When my tech approached me about the reflash I almost said no, but then he said that D/C's are updating the program and it is overall better for the engine. I believe him on that point, but mine being the C&C, seemed to be trouble free and could of gone without it. TDR member "EB" had an issue at 150K (I think) but it turned out the tech flashed the program for the regular pickup, and his C&C didn't like it. Overall, I have gotten used to it, and when my EB engages at idle I know I'm in regen, and just drive it slow. Even if I wanted to drive it at faster speeds before I hit the 2K RPM mark, it is too sluggish at the lower RPM. Mine never did this before, and it seemed to react like my 04. 5 at 325HP. You know what they say "win some lose some". I'm hoping that the programmers can change this once they catch up with the C&C ECM's. By that time I'll be out of warranty.

 

[PFranzese]

I noticed the same kind of off - on throttle transition hiccup. I noticed it right after the J35 reflash. I just learned to transition the throttle gently during regen and I guess I have to live with it.