shonuff53

iTrader: (3)

last week I notice a little bit of detonation under boost so I check tune and decided it might be my plugs. I replaced plugs today and now there is no detonation but the power seems to not be all there. A little after full boost I am feeling a smooth flutter but the rpms go up, boost is constant around 16psi, and the air/fuel is low 11's constant as well. The smooth flutter seems unusual but the car does not throw cel and idles alright.

I checked compression on all cylinders and they were from 155-160 which I believe is good.

I double checked spark plug gap including pulling them twice to do so and they are at .028 where I left them.(the first time was .030)

any ideas?

my car is 1jz, 550cc inj, 264 cams, 6465 turbonetics billet, Map Ecu2. those are the main goods.

shonuff53

iTrader: (3)

I'm not sure if boost leak is a possible problem because the boost seems to be stable. before this problem started boost level would move around a bit more. not sure if this is significant.

Access

wat happens at a lower boost?

shonuff53

iTrader: (3)

not sure what you're asking.. the lowest I ran was 15psi I turned it up a bit to 16 it seems the same. Tomorrow I guess I could try turning it all the way down and see what happens.

Access

ok.

have a look;

http://www.youtube.com/watch?v=nCj6Spwl1CU

similar?

shonuff53

iTrader: (3)

no its not compressor surge.. I've had this setup for a while its not an old problem and its definitely not surging.

Access

oh. so wat do u mean by 'flutter'?

shonuff53

iTrader: (3)

its a smooth sputter, rpms will continue going up as stated and boost does not scrabble its also stable so is the a/f ratio. It is not a hard sputter like detonation or fuel cut etc etc it is SMOOTH yet noticeable. It will go into boost normally but about the time it hits full boost is when it happens.

shonuff53

iTrader: (3)

I tightened about all the hot side intercooler connections, and checked all exh manifold nuts to make sure they were tight. I don't think I have an exh leak but Im not 100% sure.. I disconnected the radiator fan and ran the motor to see if there were any obvious exh leaks but found none. If I have a chance tomorrow Im gonna hook up one of those caps on the turbo and pressurize the system to see if there is any boost leaks somewhere..

all suggestions welcome

addisonblc

iTrader: (4)

you check your coils packs for cracks yet? mine did somethin similar to this a while back. the car didnt feel like it was gettin any of the power it should be but it was still accelerating. checked my coils and they were cracked. electrical taped um till i could buy new ones and it ran like a champ.

shonuff53

iTrader: (3)

to be honest I haven't really looked at them yet but I'll check em today, I've never had any problems with them so Im not sure what I'm looking (as far as the cracks) for but the good thing is that I have a whole spare set that is in real good condition. Im also capping off my intercooler system, smoking it then looking for leaks today.

meangreen1

iTrader: (13)

I wouuld bet on coil packs. My buddy had your same issue.

shonuff53

iTrader: (3)

well you guys guest it.. Thanks I can't believe I waited till last thing to check them, I pressurized the system, looked for exh leaks, looked for int manifold leaks, found some crappy wires and fixed them, but the whole time it was my crappy coil packs. I put some liquid tape on all the cracks and the car is running strong again. Time to order a new set I'll probably get those upgrade ones that suprastore.com sells.

addisonblc

iTrader: (4)

sweet glad to help man.