missing and stumble around 2800rpm

[PA Stroker]

i've been a member here on the sit for awhile but this is my first post. anyway i 2001 7.3 the motor is brand new with maybe 5000 miles on it. i have a slight miss and idle and all the way up through the rpms if i free rev in neutral. its also is hanging up at 2,800 or so rpms its not smoking or anything. i have ff 250/200 injectors irate t4 with s467 irate full fuel system and beans custom tunes its still does it without the chip in. i replaced the ipr no change (had one sitting around) the icp is brand new and i had a snap-on scanner on it no codes, pass buzz test and contribuation. in stumped.

 

[Rideracelivemx7]

sounds like a bad injector or possibly got unplugged in the install. its happened to me before

 

[TARM]

Do you have any codes or a CEL?

I would be thinking a loose or shorted connection between IDM and injector. Likely at the UVC, loose connector at UVC/injector, or where the main harness goes over the VC a brae wire short.

After that maybe a injector not fully seated or the like.

 

[PA Stroker]

nope no codes. i did a buzz test and it passed. all 8 sounded the same. contribution showed 8 as failed but i think it was because of the cps. the truck seems like it smokes more than it should. also it i dont know if its related but my lope tune wont work very well and when i switch tunes it has a choppy idle for a bit.

 

[neverkickn]

nope no codes. i did a buzz test and it passed. all 8 sounded the same. contribution showed 8 as failed but i think it was because of the cps. the truck seems like it smokes more than it should. also it i dont know if its related but my lope tune wont work very well and when i switch tunes it has a choppy idle for a bit.

does it fail #8 consistently? You said it smokes, is it black?

 

[littleredstroker]

I noticed mine after inj install when I was at 8k feet in the mountains pullin a trailer in low range, rpms were 2500-3000 as far as the driving went it was absolutely fine but the motor sounded like it was missing horribly, running irraticaly , talked to beans and he said it was a tunning issue and a live tune would fix it.. any chance that's your issue too?

autocorrected by taptalk

 

[littleredstroker]

And mine also has a choppy idle for a few seconds when.I switch tunes

autocorrected by taptalk

 

[PA Stroker]

does it fail #8 consistently? You said it smokes, is it black?

its black and yea number 8 fails wit a certain cps dont remember which one. forgot that is has a haze at idle no matter which tune im in.

I noticed mine after inj install when I was at 8k feet in the mountains pullin a trailer in low range, rpms were 2500-3000 as far as the driving went it was absolutely fine but the motor sounded like it was missing horribly, running irraticaly , talked to beans and he said it was a tunning issue and a live tune would fix it.. any chance that's your issue too?

maybe but it misses without the chip in there too. mine sounds like its missing and you could fell it missing too.

 

[neverkickn]

its black and yea number 8 fails wit a certain cps dont remember which one. forgot that is has a haze at idle no matter which tune im in.

I would erase that from your memory when it comes to diagnosing this particular problem. You have a miss. Number 8 continually fails contribution. So pull the vc and have a look at #8.

It is kinda tucked in behind the firewall a bit so you might have just not seated it good.

 

[Dieselboy.]

Id investigate cyl #8. Grey one is the one that fails injectors.

Check them with a strait edge. Did you make sure you got all the copper washers out ?

 

[PA Stroker]

yea it was fresh motor when i put them in. but i have to check it out. im thinkin maybe i pinched on o-ring or something when i put them in? i think there all fully seated i put them in on the engine stand so i was really able to push on them.

 

[neverkickn]

Push? Hell, I use a rubber mallet. Don't smack the hell out of them but light love taps will do the trick.

 

[TARM]

littleredstroker,

Did you have the tuning updated and it took care of the issue? That would help to show it really was the tuning and not something else.


PA Stroker,

If its smoking even at idle without any issues from the injectors or wiring its sounding more like tuning. Have you scanned the HPOP ICP and IPR% with rpms? If you can do it. If you have what were the numbers?

The 200% can take a little tweaking to get just right for smoke etc. If it turns out to be the tuning I would think with a couple tweaks based on your feedback and any data logging you can provide them any missing, smoke @ idle, and at light throttle and cruising they should be able clear those issues up. While to get it "?perfect" can take live tuning, based on my experience with Matt and his tuning, tuners can get quite close with remote adjustments to the tunes if you can provide them with accurate feedback and data logs. I would think the same would be true of Jonathan@ Beans, Swamps, PHP etc.

 

[TARM]

Push? Hell, I use a rubber mallet. Don't smack the hell out of them but light love taps will do the trick.

I fully agree. I have had some that with your hard push or at most body weight I could get to snap right in. Then there was one a couple times ago that was an easy to get to #2 injector that took a couple spirited raps with a dead blow hammer to finally seat. Then a time latter with different o-rings on they all went in with only a heavy push. How and what they are lubed with, variation in OD at the o-rings, condition of the cups I think can all have an effect.

 

[PowerstrokeJunkie]

Or it could be that your engine is significantly modified and it may just be the nature of the beast? :shrug:

 

[TARM]

Or it could be that your engine is significantly modified and it may just be the nature of the beast? :shrug:

I would hope any INTENDED internal modifications for a street engine would not entail bad missing and pouring bad smoke at idle. :shrug:

 

[PA Stroker]

PA Stroker,

If its smoking even at idle without any issues from the injectors or wiring its sounding more like tuning. Have you scanned the HPOP ICP and IPR% with rpms? If you can do it. If you have what were the numbers?

The 200% can take a little tweaking to get just right for smoke etc. If it turns out to be the tuning I would think with a couple tweaks based on your feedback and any data logging you can provide them any missing, smoke @ idle, and at light throttle and cruising they should be able clear those issues up. While to get it "?perfect" can take live tuning, based on my experience with Matt and his tuning, tuners can get quite close with remote adjustments to the tunes if you can provide them with accurate feedback and data logs. I would think the same would be true of Jonathan@ Beans, Swamps, PHP etc.[/QUOTE]

the IPC was 550-600~ at idle with 10% dc i dont remeber exctaly what it was reving up. im gonna pull the number 8 tomorrow and check it out. im thinkin i might have a problem with the copper washer or an o-ring.

 

[BDP Tuner]

PA Stroker & Littleredstroker

I think you are on the right path to finding you problem but I also think TARM is right the 200% can be a little tricky sometimes. If you have any questions or need me to work with your tunes PM me and I will help out any way I can.

 

[TARM]

There ya go. So once you figure out if its the tunes or not sounds like the support is there for ya if that does indeed end up being the issue.

Post up some of those numbers from some roll ons with the throttle and lets see what the HPOP is doing. I doubt its the issue though.

Could very well be a combo of things. Needing some tune tweaks and maybe combined with some boost or exhaust side leaks.

Then again maybe like me you have a injector nozzle that has a crack in it and will eventually let go. I had symptoms I just could not nail down. My setup did it for me when the nozzle finally let go fully. Not saying this is your issue though. I did not have a bad miss though. I had a bit of a rough idle that I could notice but had all the smoke issues. When it let go forget about it. Anyone that has one or seen one can tell you there is no mistaking it LOL

 

[PA Stroker]

well i still havent figured out the miss but i have bigger problems no i blew the tranny last night. i lost all gears and reverse. the thing is when its cold it'll move but once it gets some heat it looses everything. then if i shut it off for a few minutes i get gears back for a brief time then loose them again. i think the front pump is fried of the tc is gone? i'm lost again