Rough idle?!

Lbzmaxx

Member
Jun 16, 2016
76
0
6
Michigan
155k stock other than 4" exhaust and edge evo programmer set on 2 which is fuel econ

If I am sitting with the truck running it will idle rough then smooth then rough then smooth etc.. doesn't matter if I have ac on or heat still does it....if I bring the Rpms up a tad bit it will clear up if I bring Rpms even more up to about 2300 it is rough again go just past 2500 it's clear from there on (not 100% on the rom range 2300-2500 may be more 1500-1800 have to check that when I get out back in the truck). But for an idea how the idle is screwy that's what it does

I run diesel kleen Ceitine boost and winterizer anti gel
Summertime I have been addding a quart of ams oil marine 2 cycle ashless to every other full tank
 
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Lbzmaxx

Member
Jun 16, 2016
76
0
6
Michigan
I would compare it a gasser with a bad egr. Could a dirty egr possibly be a culprit? I seen very bad pics of these diesels with horriable clogged and dirty egr's. hence why guys say to delete the egr?!
 

bbolden516

New member
Jan 21, 2017
26
0
0
Derby Kansas
IMO Fuel is probably the culprit, rail pressure, IE: fuel pressure regulator mite be sticking causing rough idle or hard or longer starting than normal, or the opposite, is the fuel filter housing leaking check for bubbles or dampness around fuel filter head. Also when was the last service, could be bad fuel or water in fuel check and drain out a little from the filter, its hard to say. :confused:
 

thunderhead

New member
Dec 13, 2015
1
0
0
155k stock other than 4" exhaust and edge evo programmer set on 2 which is fuel econ

If I am sitting with the truck running it will idle rough then smooth then rough then smooth etc.. doesn't matter if I have ac on or heat still does it....if I bring the Rpms up a tad bit it will clear up if I bring Rpms even more up to about 2300 it is rough again go just past 2500 it's clear from there on (not 100% on the rom range 2300-2500 may be more 1500-1800 have to check that when I get out back in the truck). But for an idea how the idle is screwy that's what it does

I run diesel kleen Ceitine boost and winterizer anti gel
Summertime I have been addding a quart of ams oil marine 2 cycle ashless to every other full tank

Hi did you ever get it figured out? mines doing the same thing .