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Hey y'all! Any else run into this problem? I've been boosted for well over 80k and the motor is still healthy and well. While driving home from class I noticed that as soon as I touch into boost It starts to mis fire and run lean. Or if I'm just cruising at highway speed and add some throttle it starts to buck pretty hard. So far I've replace the coil packs and maf to no avail. Maybe 02 sensor?
 

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Injectors may need a cleaning.
 

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Hey y'all! Any else run into this problem? I've been boosted for well over 80k and the motor is still healthy and well. While driving home from class I noticed that as soon as I touch into boost It starts to mis fire and run lean. Or if I'm just cruising at highway speed and add some throttle it starts to buck pretty hard. So far I've replace the coil packs and maf to no avail. Maybe 02 sensor?
Did you try re selecting your UpRev map, assuming you have UpRev. Pretty positive you do.

While this may seem an odd suggestion....I and other people have randomly gone into no map land. And I only have 1 map. So its not like it was on the wrong map. Selected map 1 and it was fixed :dunno:
 

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Did you try re selecting your UpRev map, assuming you have UpRev. Pretty positive you do.

While this may seem an odd suggestion....I and other people have randomly gone into no map land. And I only have 1 map. So its not like it was on the wrong map. Selected map 1 and it was fixed :dunno:
this^^^ Myself and Yogi b have had the same issues, it just randomly will lose its flipping mind, slap it back into tune and its fine. Mine did it to me one day pulling out of a parking lot, slow pull out, car died, half way out into the road with traffic on the way... quick tap of the cancel and brake, tune 1 blink, back in business.
 

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i have had this happen twice
1st time it was the throttle body
2nd time map slip



now i searched, as best i could
according to whats out there

thats conspiracy theory
false news
or just nonsense

no such thing as "map slip"
[i made that word up, don't know what else to call it]


feel like i'm claiming i saw a ufo

but here are three witnesses who love uprev and are not trying to knock them [pun]
 

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this^^^ Myself and Yogi b have had the same issues, it just randomly will lose its flipping mind, slap it back into tune and its fine. Mine did it to me one day pulling out of a parking lot, slow pull out, car died, half way out into the road with traffic on the way... quick tap of the cancel and brake, tune 1 blink, back in business.
if you have ever lost an engine,
this is very scary stuff

i used to break a lot of parts [i'm retired now]
generally speaking, i'm familiar with how the car feels, when common parts break

so when this happened the 2nd time
i said self, just change the tb
no go

changed the maf [i had spares]
no go

desperate
changed plugs
[they were black with carbon]
no go

disconnected battery
let it sit

when reconnected
no go

then, just having nothing else i could i could think of
RESET uprev

viola'

Dave was the only other person who had reported this prior




could be coincidence
but
all three are turbo
2 of the 3 are very hard users [comp or track use]
 

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Vacuum leak! I just went through this. Double and triple check all hoses. You've got a vac/boost reference leak. I had the same exact problem.

Sent from my Galaxy S6 Edge+ using Tapatalk
 

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Discussion Starter #8
hmmmm never woulda thought of that! i have 5 maps however? could that still be an issue. Also how do you go about resetting uprev? i havent used that software in years and god knows where the original roms are.
 

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Discussion Starter #9
Vacuum leak! I just went through this. Double and triple check all hoses. You've got a vac/boost reference leak. I had the same exact problem.

Sent from my Galaxy S6 Edge+ using Tapatalk
ill definitely go double check. Did yours still idle okay with a vacuum leak?
 

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Did you check the spark plugs?
You mentioned coilpacks but didnt mention plugs.
 

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Hey y'all! Any else run into this problem? I've been boosted for well over 80k and the motor is still healthy and well. While driving home from class I noticed that as soon as I touch into boost It starts to mis fire and run lean. Or if I'm just cruising at highway speed and add some throttle it starts to buck pretty hard. So far I've replace the coil packs and maf to no avail. Maybe 02 sensor?
just went thru the same thing
thought it was plugs
on changing them found a leaking valve spark plug seal on three cylinders

new plugs only helped for a few hours

check for oil on the spark plug threads


last plug on the right
100_2540_zpsdef657b3 by Barry Belgard, on Flickr
 
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