Engine/Transmission (1998.5 - 2002) Engine lopes at an idle?

[BILLVO]

I just put in BD xxx155 hp injectors along with a smarty. I just tried smarty on economy mode with comp off. This thing lopes like a gasser with a monster cam in it the whole pickup shakes. It only does it at idle if I revit to about 950 rpm it smooths out. It only does it in economy mode. I haven't tried to many combos yet with comp and smarty but comp 1x1 smarty #4 is fun enough. On 2x2 #4 smoke comes on hard here already don't see the need for now to run higher.



Has anyone else had this problem. Could it be the bigger injectors causing it?

 

[DLausche]

Mine has developed a very slight lope while in D and stopped. I have DD3 (100Hp) injectors and Smarty on #9. I was wondering if it could be the new ULSD fuel that is a factor.



-Deon

 

[BILLVO]

ULSD is not meant for our older engines unless you already updated fuel system seals. It has not showed up here yet at too many places but where it is it is very well marked for 2007 and newer only vehicles.

 

[DLausche]

We've had the ULSD here for about 4 weeks now. The pump label indicates it is mandatory for use in all 2007+ as well as for use in all general diesel applications.



What seals are supposed to be updated? From what I've read it will not be possible to get the LSD fuel not too long from now. I always thought the ULSD was supposedly OK for our older trucks. I am using an additive for increased lubricity.



Sorry I kinda hijacked your thread here.



-Deon

 

[BILLVO]

From what i've read the injection pumps need the better quality I believe Neoprene seals I think these are the better ones,instead of the regular rubber based seals. I think most rebuilders have been using them for a couple years now but there are some that are not from what I've heard and read. A lot of older pumps could be affected.

 

[BILLVO]

Back to the loping issue, does anyone have ideas why?

 

[Joseph Donnelly]

The ECM is trying to maintain idle speed. The injectors are putting out so much fuel that it is hard to keep idle speed down, so the ECM "shuts down" one cylinder at a time to bring rpm down, hence the lope.

 

[BILLVO]

It only does it in park or neutral in drive its smooth. I noticed it has a very slight lope with comp also but very slight usually while coasting to a stop in gear. also after adding smarty the cruise control is totally unusable due to extreme surgeing.

 

[EBung]

Its the injectors mine did when I put mine in and it has never changed. I dont mind it I just wish it idled a tick lower rpm so it didnt go into gear so harsh.

 

[NoSeeUm]

Mine lopes when it is cold. It got more noticeable after I put in the bigger injectors.



Jim

 

[Regcabguy]

Lope

With DD2's and now with the Mach 1. 6's,whenever I come to a halt after a freeway run,a short-lived mini-lope happens for a few seconds,then smooths out. I'm running an EZ with it. Also with the DTT,after truck has sat for awhile upon starting it I usually let it sit in neutral for a few seconds before engaging transmission to prevent a semi-stalling situation. Probably a combination of tight convertor and injector demand. Small tradeoff for the amazing performance gain.

 

[BILLVO]

I ran BD's 90hp injectors and had no lope at all. After having these 155 injectors for a week now I'm thinking they are a bit much for my needs I will run them for a little while longer and see what the overall performance will be. and may back down to either the 110 or 130 injectors. After 1 tank I figured milage went from 16. 5 with 90's to 15. 5 with these.