hmmm...intake manifold crack/leak?

[IIdiceII]

ok im going nuts right now.

I just recently finished my build.

2002 wrx
06 sti ej257 block
sti heads
wrx intake manifold, tgv's, injectors, all accessories etc.

now since Ive gotten the car finished, ive driven it about 200 miles and the whole time ive had this bad hesitation, sputtering around 4000 rpms.

be it, wot, half throttle or just getting up in the rpm's...feels like it hits fuel cut.

ive done a leak test a couple times and im doing it again. and spraying every where with soapy water. and what do i find?

on top of my COATED grimmspeed intake manifold, bubbling soapy water!!!

on the very very top of the manifold, theres a little circle, recessed part. it seems to have a pin hole leak there.

anyone hear anything like this before?

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[Haelan]

Manufacturing defect?

[IIdiceII]

i dont see how...its my stock intake manifold thats been on the car since 02 and has been on 5 different turbos, countless different tunes and pressure test's and i never noticed it.

i sent it to grimmspeed to get coated and im assuming the sand blasted it and then coated it. thats the only thing i can think off that would make any sense.

[fastnoypi]

pin hole leak by the casting button?

[IIdiceII]

im uploading a video right now so you can see...

its VERY tiny and i highly doubt it has anything to do with my hesitation issue but im just freaking out about this. one thing after another with this f'ing car!

[IIdiceII]

ignore the first 10 seconds of the video and the loud compressor in the background lol

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its really tiny leak but its still a leak!

its creating very small tiny bubbles and seems to be more than one pinhole.

[penusai]

what was the condition of the motor? mileage?

get it from a reputable person?

if not, check timing etc before you put it in?

this is ontop of the manifold, right above the TB right?

[IIdiceII]

the motor had less than 10k miles on it and i bought it from a very reputable seller. it looked brand new. oil drained perfectly clean, spark plugs were fine. I havent done a compression test or anything like that. it makes boost and idle 100%. Im pretty sure its a tuning issue. im running a modified version of my old map and there are a **** load of new parts.

I def need a tune bad but i also have a brand new clutch and flywheel that need to be broken in which is holding me back from getting it tuned asap. I need to put a few hundred miles on it before i can get tuned.

i did some logging the past couple days and just driving the car normally, its totally fine. not knocking or pulling timing or anything like that and my afr's are normal. my tuner said it didnt look bad. its only when I get around 4k rpm's and the wastegate starts opening that the car bucks and sputters, feels like its hitting fuel cut.

compared to the old map, I now have an ewg setup, new turbo, new motor, tgv deletes, ported throttle body and intake mani, perrin big maf, new turbo inlet, new header, new turbo back. and the car has no CEL's before anyone asks.

[JSarv]

So this got me thinking, my intake is painted and I took a look at that plug and on the.... passenger side of the plug itself the paint is missing for about 1/8" in the circumference and there is a black mark over the paint about the size of a ball point pen right where the paint is missing...


Weird? I'm going to pressure test it tom...

-jerod

[Uncle Scotty]

i cant play that vid, here .....but

sometimes.....when the bolt is removed from the evap solenoid the wrong bolt is put back in....one that is too long....and it gets overtightened and cracks the mani in that area

[JSarv]

Originally Posted by Uncle Scotty

i cant play that vid, here .....but

sometimes.....when the bolt is removed from the evap solenoid the wrong bolt is put back in....one that is too long....and it gets overtightened and cracks the mani in that area

I started that thread... (Or I think I did?) That definitely happened to me...

His leak is on the very top of the manifold, where the "freeze plug" is located...

[Haelan]

Originally Posted by Uncle Scotty

i cant play that vid, here .....but

sometimes.....when the bolt is removed from the evap solenoid the wrong bolt is put back in....one that is too long....and it gets overtightened and cracks the mani in that area

That happened to me as well. Pulled that aluminum 'tooth' forward and ripped it right off. Had to beat it back on with a hammer and JB Weld it until I got the manifold replaced.

[JSarv]

I actually ran a long enough bolt in, it ran into the runner for # 1 and put an in. long crack in the runner

[Haelan]

Originally Posted by JSarv

I actually ran a long enough bolt in, it ran into the runner for # 1 and put an in. long crack in the runner

"Oh look...a loose bolt...I can't have that!"

Crank crank crank...snap...misfire misfire misfire misfire...sputter sputter sppuuutteerr...

Mine didn't crack, but actually drilled a hole into the runner along with pulling the tooth off. I found out later the bolt belonged in the rear frame of the power steering pump.

Item #43 I need to thank the previous owner for...

[IIdiceII]

the leak is extremely slow. you cant hear it leak and if i wasnt looking almost directly at it in that area, i would have never really noticed the bubbles. it gets more foamy than bubbly.

I'm gonna take some better video in better light tomorrow and try and take some macro pics...my manifold is coated black so if there is a hole or a crack, its REALLY hard to see.

[CKxx]

While that is leaking, and you should fix it, I really don't think that is letting enough air escape to cause a stuttering issue.

What EM?

[IIdiceII]

yea its def not my stutter prob...i need a tune thats what that is...usimg stock wrx ecu and rom raider

[ride5000]

so you're running an avcs ej257 with a 16bit usdm ecu?

[IIdiceII]

im using a gruppe-s cam sensor adapter.

edit: yea im using the usdm stock ecu with the ej257.