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so i was on my way to work this morning, taking it easy... then came up on a car going slow in the fast lane, so i pushed the throttle to maybe 75% for a couple of seconds and it took off for a second but then i lost power and it was struggling to stay up to speed... i found myself having to give it about 50% throttle just to maintain highway speed.. i got to work about 5 minutes afterwards and put the window down and could hear this horrible knocking after a few minutes of walking around and cursing a bit i noticed that the knocking was gone?? i shut it down for a couple of hours and went out and started it again on my break and no knocking, but sounds like it's running on 4 or 5 cylinders.. the engine is real rough idleing and i can smell gas while it's running.. obviously unburnt fuel is going out the exhaust.. i checked with my scan guage for misfires and its saying 0.... but it aint running right... i wasn't watching the kr at the time but i know that there wasn't any cause i've checked before with the same amount of boost at wot, 0 kr... what the fu#% happened??? oil pressure is good.. starts easy.. i 'm to pissed to look at the thing right now.. just sat down for a cold one and going to relax for a bit.. i guess the first thing i'll check are the spark plugs and do a compression test across all cylinders. anything else i should check before i start the teardown?

you might want to test your coils

are any codes coming up ? is there a check engine light on? if your having that servere of a problem i'm sure the computer should of picked something up

no codes, no engine light, coils are brand new....

Sure sounds like you may have lost a cylinder but don't jump to conclusions. Need more info.

i'm trying not to jump to any conclusions yet.. we'll see how the compression test turns out....

Sounds very familiar. Last time that happened to me, I had chunked a piston. The chunk squashed my spark plug on the #1 cylinder closed, effectively shorting out the spark loop for both cylinders on that coil.

A couple months later, I installed a replacement motor. My compression test was still pretty good, with no big red flags. Yours may be the same (it was only the rim of the piston that chunked). This chunked piston would now be very prone to knock due to the sharp edges heating up. My diagnosis was made with a borescope through the spark plug hole. I have pics of the damage I shot with my camera through the borescope, and after I removed the heads, but it looked almost identical to the one in this topic:

viewtopic.php?f=12&t=8486

That's the top ring exposed where the chunk is missing. You can drive this way, but I would seriously retard boost and timing while you search for a solution (replacement or repair).

Just tossing this out there as a very strong possibility, particularly in light of your turbo setup.

since this has happened the engine has only ran for a total of about 15 minutes.. i work 35 km away from home, i had it towed home just as a precaution not to do any further damage.. what bugs me is that i wasn't even driving it hard, and after spending upwards of $7000 building this motor i expected it to last a little longer than 20000 km....... oh well, back to the drawing board.. i'm jumping to conclusions again...

im telling ys its tootally sounds like a coild isnt workniog right.

His drunkenness strikes another post!

Hope you get it fixed man. 7 grand building the motor? I'd be pissed too lol.

i still got my old coils, the new ones are oem's that i got from zzp. they only got about 3000 km on them.. i suppose it's possible that they're not as good as the originals.. i'll probably try swaping each coil with a old one to see if it solves it.. but that doesn't explain they knocking that i heard just after it happend? like i said before the knocking is gone now.. what does this mean? i'm trying to find a place to rent or borrow a borescope to have a look to see if i chunked a piston

There's no point in doing or checking anything (or driving for that matter) until you pull all 6 plugs and inspect them. Keep them in order or number them.

yeah, i'm gonna pull the plugs one day this week.. i'm in no rush... i'll keep ya posted

What was the temp outside when this happened? Just curious. Hope everythings alright.

Hmmmm.....a non intercooled turbo.

yes, a non-intercooled turbo............. i was running 12 psi with 0 kr.. the temp was about -5*c.. at about half throttle something let go and lost power.. seems most likely that i chunked a piston and crushed the spark plug. i suppose your implying that the lack of an intercooler is the cause??

Nope, the added density of the air in a part throttle condition is a more likely culprit. I guess since we're making assumptions, the above mentioned with ZZP's lack of mid throttle tuning......which I don't believe they when they do a standard dyno tune. At WOT you probably would have been ok because they tend to tune fat up top. Again, I'm assuming you had the car dyno tuned by ZZP for the above mentioned items, if not, my appologies to ZZP.