need help misfiring and popping at boost

[90_240sxx]

long story short my car was running on 2 cylinders when it first started to act up . but now its miss firing and its popping at boost around 6 or 7 psi and it wont pass over 7psi. i changed out my spark plugs fuel filter fuel injectors and checked for boost/vacuum leaks any thing else that can cause this. and it was running fine before it just took a dump on me out of the blue. and when it pops the boost peaks up. oh and how do you check the coil packs to see if there going out? oh and its a s14 sr20det

[JRPS13]

coil packs

[90_240sxx]

my car is running on 3 cylinders again i disconnected each coil pack one by one and it seems that number 1 is not firing and number 4 is firing weak. so i switch the coil packs around and still number one is not firing and number 4 is still week so its not the coil packs right? can it be my ignitor chip? im getting a new one on tuesday. can my CAS be the cause of it?

[Mr Lee5353]

my first cylinder isnt firing either. i have both spark and fuel, pulled the rail off to see if injectors spray, flipped coils, and ive done the good ol' pull the plug out and stick it in the coil to see if it sparks test. all tests good.

[90_240sxx]

got the new ignition module and new spark plugs again and its running better now but still misfires at idle and at 7psi. what the f**k how can i be sure its my coil packs?

[90_240sxx]

can a low compression be the cause of this????

[Mr Lee5353]

possibly, but mines doing it too and ive got 150 across all four.

[nzmoman]

I would double check the vacuum again. What you are describing has been the culprit in two of my cars. Simple small leaks in a hose that allow you to make pressure but the actual amount of air getting into the engine is less because of a small leak somewhere. I'd hit 7 psi when the car should have been running 9 and it wouldn't make it much past that. It took three rounds for me to find the leak the first time and the second time, I removed all of my piping and just reinstalled it to make sure I got a good look at any problem areas. Also check your turbo outlet neck for any loose piping or bolts or messed up gaskets.

symptoms usually are really bad gas mileage, maybe a near stall at idle, and definitely running rich.

[90_240sxx]

changed out the vac lines and even tried a different mass and its still doing the same thing. can a bad cas be doing this or a bad chain tensioner. can they mes with the timing that it would cause it to do that?

[90_240sxx]

bump............ anyone???

[Koshin]

have you checked your timing???

[90_240sxx]

yes and i even played with it around and it still does the same thing. was asking about the cas and the timing chain tensioner cause with the timing light it seemed that the timing would move a little by it self. and at what mark is it to be on any ways?

[Koshin]

2nd mark from the right...15 btdc

[90_240sxx]

you mean 15 after top dead center not 15 before top dead center right? right side as in the passenger side???