rough idle in gear - coasting or stopping

[thartman]

I have been searching and reading the threads and haven't really come accross one that covers my issue. I have a 02 - DMAX w/Ally (53k), 4" turbo back exhaust with Magnaflow, & Juice w/Attitude (usually run in either 2 or 3).

It started around 1 month ago - when I stop at a light - right before a total stop the truck starts running a little ragged - like the timing is a little off (don't know how else to explain it). When I come to a complete stop - the raggedness goes away - however the idle seems a little rough. I watch my RPM readout on the attitude and it is hovering around 670 - 680.

When I let off the brake and coast (in gear) the roughness / raggedness comes back. Give it the pedal and everything seems OK.

Changed out Fuel Filter already (1 week ago) and same thing. I run PS additive about every other fill up. Thinking about bumping up the dose on the next one.

For the last 2 days I have been running in level 0 just to see if anything would change - no change.

I have read all of these things about Fuel Pumps, injectors, .......... and I know it could be anything or any one of these.

Just wanted to bounce this off of all you for suggestions before taking the Juice off and giving it to the dealer.

Could it be a computer upgrade? When was the last upgrade for the LB7?

Any suggestions would be greatly appreciated and if more information is needed let me know that too.

thanx
tlh

[copperhead]

So, its not surging?

[thartman]

oops - sorry about that - yes I am experiencing surging as well.

[bcnqrgd]

Mine did that for a couple of years then started smoking at idle and, finally, the General bought me a set of injectors and the problem went away...

[Tough Guy]

Does it so it with the Edge box completely removed from the vehicle also?

Chris

[thartman]

Yes - it does it with the Juice removed completely as well. I drove around a day or two without the Juice and finally just took it in to the stealer. After monkeying around with it for 1/2 a day and scratching their collective heads - I explained to them exactly how I wanted them to troubleshoot it:
1) drive truck until it gets warmed up / hot
2) take it back to shop and diagnose it
3) diagnose it in gear (please put emergency brake on - sometimes you just have to spell it out!!)

Once they did that - they finally got the reading that everyone needed: two injectors were out of spec.

They are changing out all 8 injectors as we speak - keep everyone informed if that fixes the issue.

thanx for all the eyes and suggestions.

[thartman]

Well, got truck back from dealer late Friday with 8 new injectors - drove it around all weekend - so far so good - took care of the rough idle and rough coasting. Put Juice back on and truck runs great - so far. Hopefully that was the ticket - if not - at least I got new injectors!!