[prorida]

just wondering who has a jump in idle? these morning start ups are hard on the old girl, and i noticed a jump in the idle a month or two ago. and i finally decided to ask around.

This is what it is doing, start it up and the idle does not stay at the same rpm. jumps up about 1hundred rpms for about a second, about every five seconds. and it very consistant, you could dang near set your watch to it. It only seems noticeible because it's straightpiped, so when i'm in the cab i can't really feel or hear it, i just see it on the tach.

I don't really think it's a big deal, but i might as well ask. who know's maybe you guys will tell me "thats exactlly what happened right before my lb7 burned to the ground. "

oh ya 20k on new injectors, and the balence rates were fine about 4k or so.

 

[duramaxdiesel]

Kinda like a romping sound huh?? I believe it's the Fuel Pressure Regulator Valve. I see that you have an '03 so you should still be covered. It will only get worse with time. Let the dealer take care of it now. What a PITA to change.

Nick

 

[prorida]

is that covered to 200k if not i'm on my own.

 

[duramaxdiesel]

Sorry. No, that ain't covered dude. If you want to bandaid the problem just use Power Service in every tank like I did. Cleaned it right up and was idling smooooth.

Nick

 

[Tolliwacker]

I used Lucas a few tanks, and now I use DieselKleen in every other tank, it cure my problem for the last 10-11K or so, I haven't seen the problem since.

 

[mvnvltn]

Is your windshied defogger on? That will do it too.

 

[prorida]

Is your windshied defogger on? That will do it too.

Say what!!! never herd of that, anyone else herd of that?

 

[HD2DMAX]

Say what!!! never herd of that, anyone else herd of that?

Actually yes...the a/c compressor cycles causing the idle to fluctuate.

 

[astieg]

Weird?? Wonder-woman oh not idol idle A\C on will do it....

 

[prorida]

Weird?? Wonder-woman oh not idol idle A\C on will do it....

:cookoo:

 

[mvnvltn]

Actually yes...the a/c compressor cycles causing the idle to fluctuate.

:exactly:

If your charge is low it will cycle more than if it is fully charged.

 

[astieg]

only pure intentions :angel: when watching that show back in the days.

 

[prorida]

only pure intentions :angel: when watching that show back in the days.

right right so if it's not the defog it's the FPR.. huh... got home today and it was warmed up and idleing fine so i turned the defrost on and it started doing it. then turned it off and it kept doing it. oh well, i give up

 

[got-h2o]

The defrost/ac probably wouldn't do it either. Maybe on a gasser. I had the same thing on my 01 lb7 w/196,000. Before mods and after. Changed the fuel pressure regulator-still did it. New mass air-still did it. Injector pump failed in the meantime-still. Since, it's had an entire new top end (head gaskets up-including injectors, etc-big$$$). Still does it (a buddie of mine now owns it). I thought that it was just natural, but my 02 doesn't do it. I wouldn't spend much time and $$$ on it unless it becomes a bigger problem. JMO.