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EDIT: Look at post on page 2 for results.

My cars giving me grief again and i dont know what the hell it is. Quick rundown

r33, stock turbo at 0.9bar, walbro fuel pump, jj cooler, pod with box, fpr, turbotech bleed valve, hks FCD, kakimoto 3 or 3.5" full exhaust with unkown cat

dynoed at 204rwkw last time. 13.5 qtr

drove to QLD and on my drive there i felt the car lose all its balls. looked at boost gauge and it would drop from 0.9 to 0.6bar at redline so i though it was the apexi pod i put back on

i done the intake pipe mod to re-enforce it and changed back to other pod, also cleaned afm and aac valve. no change

changed BOV from atmo to stockie, no change

sparkies are 20k.s old, platinums at 1mm gap which i havent checked yet

now without going and spending cash on dyno runs etc which i may well have to do i want to know what the likely hood of a blocked cat is and if this is causing the power loss??

it does not feel like it is misfiring and i have rechecked all IC piping clamps and they seem secure. Also changed a couple vacuum hoses here and there

oil pressure it a tad higher than usual (prob not related) but maybe coz i slightly overfilled. It slightly sits above the first line on the gauge on idle and just over 3/4 on full load

i rekon no way its the cat and ill just waste my time pulling the exhaust off (scared of undoing those rusted nuts lol)

any input??

Edited by tek_01

Does it also make boost slowly ??

If so then I would definitely check your cat. I mucked around for ages trying to find why my car struggled to make boost. The cat had collapsed and was causing a large amount of back presure.

Tim.

so it looks like it could be the cat

it is laggy i guess but it has always been like that, under 3.5k it is useless even tho it is standard turbo

in case it is the cat, what is recommended? i hear metal cat is the go but lately a lot of people have had theirs fail

Im having a similar problem. More lag from low rpm and not as sharp when i press the throttle. Around town sounds like i'm driving an NA :P

I'm guessing its either wastegate actuator stuffing around OR this thread made me think it could be exhaust blockage. It's rusted out after the cat so i might pull it off and see what happens.

yeh just make sure u secure the rest of the exhaust if u leave it on lol. dont know how it will drive with no exhaust tho??? ive had holes in my old car and it wouldnt bloody move

turbos are some temperamental!!!!!

if the cat has shit itself the sensor should tell you it has. i'd be checking the plugs before you dish out money, and/or changing them to 0.8 gap rather than 1.0mm.

can you hear any sort of high pitched hissing noise under boost? have you checked all your piping?

Edited by dmr

to be honest i wouldnt know how to identify pinging. would prob have to get a pro to look at/listen to it

no hissing to speak of apart from the vacuum sounding air filter lol

why should i re-gap if it is not missing???

i would be able to feel if it is missing wouldnt it?

I have a similar problem but I know for a fact it's not the cat.

I can set 0.9 bar and it will hold that for a short while and will then drop off to about 0.6 bar like you, strangely I also made 204rwkw's. Also my turbo is very responsive and will raise boost very fast, untill higher RPM.

I have checked the usual things like rubber intake pipe sucking in, wastegate pre-load (which I increased with no better sucess) now I am thinking maybe it is a restrictive exhaust. I have a 3inch stainless dump/front, 4 inch stainless catback though it has two mufflers and even with 204rwkw's the car is very quiet..... I was thinking of just dropping the exhaust at the cat for one run to see if the boost holds.

I have also been told that maybe the stock Turbo is just running out of flow, maybe but hardly anyone else has that prob.

Edited by FighterJoe

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