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Missing under load

IBLOWN

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Ive always had a slight miss under load (midrange on boost) for a few years now but only when it got hot (about 1/2 on the temp gauge). It wont do it when the motor is cold but as it warms up the miss becomes very noticable.

Last couple of drives its getting worse.

I did a data log with EFILive and found it to be knocking which inturn retards the timing.

It really feels like an ignition miss to me. A/F mix is at 11.7-12.5:1 so fuel is good.

If the engine misses i think the knock sensors will pick it up as they are programmed to listen at certain times i.e when detonation usaully occurs (i think..) So to me if the engine misses and the knock sensors pick it up they either think its a knock or something else bad and retard the timing for safety.

Im not sure, just wanted to see what you guys thought. Maybe the DFI module and or coilpacks are getting hot from the turbo's? Maybe bad earthing to the DFI?

Leads are good and plugs are good.
 

immortality

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what plugs are you running, gap size? heat range? could also be oned dodgy injector running the cylinder just a little leaner then the rest
 

IBLOWN

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Im running the stock S/C V6 plugs.

See this only just started to happen badly the last couple of drives ago (about an hours worth of driving) I cant think of what i changed to make this happen all of a sudden.

The injectors are relatively new. Could still be them though.
 

immortality

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i'm not sure what the L67 plugs are or what gap they run. however the stock L67 runs less boost then you do so maybe try closing the gap a touch. maybe get foam to alter your tune and make the intake temp correction a little richer
 

delcowizzid

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email me a log and ill have a look for you i tune by them every day so i know what im looking at my email should be in my profile.it could be CAS or module or coils breaking down but allways worth a look in a log
 

delcowizzid

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sweet as mate ill let you know what i find in there
 

delcowizzid

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ide say the miss is on the drivers side bank the O2 sensor marked right in the logs is all over the show quite a bit .do you have a wideband cause going off narrowband O2 volts its leaner than i run my stock NA tunes.didnt see any knock in the logs its at 880mv i run at 890mv NA for wot which is as close to 13:1 as a rough guide ide want to be well over 900 on boost
 

IBLOWN

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Thanks for that.

The Ecotecs always run leaner on the bank the T/B is on. My T/B is on the drivers side now. Although i did notice the difference is a little excessive. Like i said even after running it alot richer it still missed.

What is the retarding for?
 

delcowizzid

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it is running the auto VS bins yes cause thats the def i was using maybe i didnt get to the point of where the knock is to many interuptions.ide say you have a plug dropping out or a lead on the drivers side cause the o2 isnt just leaner its bobbing like its the missing side.got any logs of it richened up
 
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