Engine/Transmission (1998.5 - 2002) Idle lope / Rough idle after Jammer II install

[Eric Lee]

I just installed some Jammer II's - tonight, and something about them or the install, I'm 'loping' at Idle now. She's running pretty smooth, at least it feels like it in the cab with the windows closed. Open the window or walk around her and the lope is very evident.



Install went well and followed DD Install Instructions closely. I cracked the 19 mm nuts and bled like PDR advised. These came from PDR so I'm putting my money on the fact that they are balanced and right.

Took her out on the highway and opened it up. These are AWSOME - These are the kick in the pants I've been trying to find. Came home and still have a disheartening rough idle.



I really don't want to reset APPS - if I don't have too - the throttle works fine. I thinks the guy in the hopped up 5. 0 needs to reset his though ---



Thanks in advance - Eric

 

[PC12Driver]

If you have the lope while you're in gear, that's probably normal. The computer can't keep up with the much-more-responsive-at-idle high performance injectors. The little squirt that the computer commands to bring the idle back up is now a big squirt, and the engine overshoots its idle speed. So the ecm cuts the fuel back, the engine drops below idle speed, and the cycle starts over. Without a load on the engine you should have a smooth idle, and the loping should start once you put it in gear (autos) or feather the clutch (manuals).



So, it's normal ops. Some might even call it an improvement...

 

[BRobertson]

I installed a set of Jammer 2's (from Piers) a month ago. My 01 idles smoother than stock.

Bob

 

[Eric Lee]

Bob - Did it have a rough idle right after you installed them and then straighten out with a little time? Have you ever done the APPS reset ( battery unhook - pedal thing) ?

- ERic

 

[BRobertson]

Eric,

No, the idle was smooth from inital start up, and I haven't done the APPS reset.

Bob

 

[Eric Lee]

I had to bump the starter twice this morning to get the motor running - usually fires right up. Makes me think that air is getting in the lines somewhere. Still have the rough idle. I'm pretty sure it has to do with my install. I followed directions well - maybe with the exception of tightening up the injector line clamps before tightening up 19mm nuts. If that is the problem and I tightened the tubes off center, is there a possibility that I have damaged the line ends? I cracked the 19mm a few times but never fully relaxed lines before doing so -



Should I pull the injectors out and reinstall?

What joint would be the most probable cause of air leakage.

How do I know that the crossover tube is seated correctly?



The Jammers fell right in and the stock ones had to be pulled out with moderate force. Should I take O-rings off stock injectors and put on Jammers to tighten up fit?

Are there different diameters where the O-ring seats that would make a difference with operation?

Is it important that these O-rings seal?



I was having a nice dinner with a hot blond tonight and all I was thinking about was how my truck was running.



Any help with simular problem would be appreiciated (I mean with the truck - not the blond). - Eric

 

[lmills]

most likely air is trapped or getting into the system. The rubber o-ring is for sealing oil. I don't think it would have anything to do with allowing air into the system. The last time I did an injector swap it took a couple days for the air to totally purge out. After 2-3 days of driving, it fired right up on the first try. Some times the air will purge out on the first run, but not always.

 

[darkhorse]

The fuel crossover tubes are pretty tough. It's unlikely that you damaged them. I had a little trouble with my injector swap. I needed to retourque the injector hold down nuts & the fuel line retainers. It helps to sneak up on the torque setting in 2 or 3 steps alternating between the injector & the fuel line. That seems to help every thing seat properly

 

[Eric Lee]

Darkhorse - That's exactly what I was thinking - The #6 fuel nut was so hard to get to I cut a wrench and only had 4" of handle and an offhand grip - I will feel better to retorque both the hold downs and the fuel line retainers - I'll get a whole wrench in there some how. I'm going to make sure the line clamps are loose when I do, to try to get them to seat as before.



Damage to the crossover did cross my mind but the injectors all went in nice after following DD's instructions and carefully prying out crossovers. I'm glad you said that though.



Which brings me to another concern and discrepency - DD's instructions state torque hold downs first then fuel nuts. Elsewhere I've read to torque fuel nuts first --- Which is it? - or niether (little on each).



Also I've read to torque the dog stuff out of the fuel nuts. (40#) -Eric

 

[darkhorse]

I used a 19 mm crows foot in my torque wrench for the fuel nuts. I couldn't get it on #6 however so & just guesstimated on that one judging by how hard I had to "reef" on the others. I think sneaking up on the torque & going back & forth is the best bet.

 

[Eric Lee]

Crows foot - check. 89 inch pounds on the hold downs and ?? on the fuel nuts?

- Eric

 

[darkhorse]

The factory service manual states 28 ft/lb on the fuel fitting nuts.

 

[Eric Lee]

Thanks - I'm going to take her back apart in the am, then back together - just different.

- Eric

 

[Idaho CTD]

Eric,



How were your fuel line ends? Sometimes they become corroded and dont seat properly. If you break the nuts loose and notice rust or corrosion then you need to remove the lines and take some very fine sandpaper to them.

 

[Eric Lee]

Idaho - I looked them over the first time I had it apart and they looked pretty clean - really everything looked clean. I will be following your advice if todays redo doesn't take.

I took everything apart again this morning with the exception of removing the injectors themselves or completely unscrewing fuel nuts. I removed the hold downs and kinda rotated the injectors while fingertightening the fuel nuts and pressing in with the fuel lines just to find 'home' and make sure nothing was cocked. I then proceeded to torque hold downs and fuel nuts a little at a time till the hold downs were at 89 in lbs and the fuel nuts were over the specified 28 ft lbs - probably between there and 40 ft lbs.

This time I did not crack the fuel nuts to purge lines after the intake and misc were reassembled and motor was running. I don't want to disturb what I got together and hope that any remaining air will purge over a short period. The idle is definatley much better and smoother - it started up after 5 hours sitting this afternoon with first bump, so if it does the same in the morning I'll concider it a done deal.

Thanks for the input all - Eric

 

[Tcolesanti]

My Mach 1. 5's idled rough for a while and after comepletly disassembling and reassembling three of four times I just drove the crap out of it. I blamed it on the computer taking its sweet time to readjust, but now it idles fine. My truck did take longer than most to readjust (3000 miles).

 

[Eric Lee]

Injectors Happy - Trucks Happy (pic) - I'm Happy

I think I got it done right - which means I can quit takin' her apart. Second time was the charm and took about 2 hours maybe a little less - half as long as the first time.



Didn't start right up this morning but driving home tonight I could tell everythings clearing up. I really wasn't buying the theory of gradual purging - I thought that the diesel would either clear it or not, but I guess I'm a believer in that now. It did take time and a few cycles of the system to make her run right.



The idle has smoothed and the injectors give power smoother and sooner. Even a slight feather of the go pedal rises idle smoothly.

I have noticed a little hazing at idle but it is getting colder.



The first night out, I ran her a little hard and noticed a trans shudder that showed up while decelerating from - well... lets say over 70. Didn't mention it cause I figured it was another problem for another day. I studied up here on TDR and read that leaking injectors can cause this and I think it's true.

- Eric

 

[Eric Lee]

Just an update - The Jammer injectors have been really nice - The truck starts right up and idles smooth, power delivery is also smooth. My egt's dropped 75deg at 75 mph. - from 775 to 700. I just installed a PDR 35HX so I'm breaking that in and haven't really tromped it yet. I did accidently light 'em up pulling into traffic the other day. Started spinning around 20 -25 mph as the boost started to climb. Now I'm thinking how nice it would be to have both tires spin - or not.



After figuring out how to correctly install and what to watch out for - I think the only thing that the DD instructions don't spell out is that you should pull out connector tubes at least 1/2" to be clear when the injectors come out to avoid damaging tip.



This swap was definately worth the time and money - Piers suggested the Jammer and I'm glad he did.