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05 Sti cylinders 1-3 not firing

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Hi.

car was running fine with some bugs to be tuned. It first started when i cleaned the maf and ground points, car was running like crap but no misfire just bad idle that cleared after 3000 rpm
later that night i started the car and magically it was all good but i did notice that the car was running very rich, 12-12.5 at idle, i went for a ride and afr was stable at 11-11.2 all the time
then after 8 miles suddently misfired and its ran like it was only with 2 pistons.

went to the mechanic and they found out that pistons 1 and 3 where off.
So we took out the spark plugs and the right side ones were completly black and soaked in gas and the left side were almost like new.

No cell, but days before got misfire con cylinder 1,3,4

Later we did this with no result:

Changed spark plugs
Changed coils 
Changed maf sensor
Checked injector pluse
Checked coil with plug for spark
Checked timing
Checked ground

Checked compression (140 psi on all 4)


What could possibly be shutting down one side of the engine ? please help beacuse we have no clue.

Mods are:

wallbro 255 fuel pump
ID 1000cc top feed conversion with fuel lines, stock FRP (recently installed)
Ks tech big maf short ram itanke
Blouch dom 3xtr
Gt spec header with invidia turbo back exhaust
Big top mount intercooler

Ecu reflash 

Wiseco pistons (recently installed)
Manley rods
Ported head (recently installed)
GSC 272 cams (recently installed)
GSC Valves (recently installed)
GSC springs and retainers (recently installed)

Car was breaking in new pistons, just traveled 20 miles no wot 

Fouled plugs could mean they're too cold. Might need a higher heat plug for the break-in.

 

AFR at 11.2 is pig rich. Is it getting out of open loop at the correct temp?

  • Author

i logged the INTAKE AVCS ADVANCE and found that right one was advancing 66 degrese.

Could that be the cause ?

 

Damaged selenoid?

Stuck sprocket?

  • Author

I have checked my VIN and it doesnt have oil screen on the avcs but it does have on the turbo. Turbo and AVCS use a common rail?  

Yes they can I have done it when I was chasing a misfire on an xt engine. Are there any cam crank correlation codes ? I had an intake gear put on that had an egg shaped dowel pin hole so even tho it was basically in time it was off just enough to cause mis fires down low. Ran fine in the revs. Just had a bad idle.

 

Also isnt 140 psi compression a bit low for pistons?

Edited by zombieforce

Wiseco are lower compression ratio pistons. 140 isn't out of the ballpark for a built turbo motor.

i logged the INTAKE AVCS ADVANCE and found that right one was advancing 66 degrese.

 

How far is the left side advancing?

Wiseco are lower compression ratio pistons. 140 isn't out of t. ballpark for a built turbo motor.

How far is the left side advancing?

Yeah I guess thats right. Im stuck thinki g about my jet ski engines any less than 180 psi and you can feel the loss of power

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