Help: Installed larger turbo, now I am SPUTTERING(FOUND A BOOST LEAK BEHIND COMPRESSO

[MarkAngelo05]

Hey there, I just installed a new turbo, the EVOIII GT housing stuffed with an 18G wheel and a 15degree clipped td05 turbine wheel. Well, the turbo I had before was a hahn super 16G, and I was boosting 15psi.

I set my boost at 15 psi with my new turbo, and when it passes 11 psi, it starts sputtering like crazy... I am running 650cc injectors with an safc, and EVO 9 Pump stock fuel pressure, with the settings at -22 all rpm's on high setting, and -25 on all Low settings. I did not change anything else on the car... well, I did upgrade to a GT ported manifold and a tubular O2 housing also, but that is all. I still haven't received my palm pilot and I already have the logger software and interface! its been almost a month since I ordered my palm pilot. but I should get it soon.

I regapped the plugs at .028, and checked out my spark plug cables. any ideas? One thing I am thinking is that since the 18G sucks in more air, than the super 16g, maybe the maf sensor reads that increase of air when it all of a sudden hits boost then starts dumping more fuel which causes it to bog/sputter when boost kicks in...?? I tried leaning it out, and it got better, But I am just a lil scared to because I don't have my palm pilot to log it yet.

What Confuses me is that the super 16G was set at the same boost level and the same settings on the safc, with the 650cc injectors and it ran fine when it hit boost. could my theory be correct on how the 18g may pull more air through the (stock 2G) maf than the super 16G did and therefor tells the ecu to push more fuel through???

Thanks so much for your help in advance!

Mark

 

[da_reeseboy]

-22 sounds pretty rich when boosting. How did you tune it when you had the 16g installed?

I would be more inclined to think that what happened is when you installed the new turbo you did what every instruction set for working on cars starts with - you disconnected the battery. Not a bad thing by any means (its what you're supposed to do), but when you did that you reset the ecu which was probably REALLY leaning out your mixture before. I am running a B16g at 19 to 20 psi and 660's and when boost kicks in, I go down to -34 on the afc. What other fuel system mods do you have? - nvm. I just went and read your mods list.

- Jesse

 

[CanadianTSi]

Most likely a boost leak.

And yes -22 is pretty rich for 650's.

 

[freshlane]

It sounds like a boost leak, but how are the lights/radio/and other acc working also?

 

[MarkAngelo05]

well, I will use my buddies's boost leak tester on it today. And yes my lights, radio, and other acc's work... umm.. what if they didn't?

So when boost kicks in, the ecu must rich things out a bit huh? I'm just running stock Fuel Pressure EVO 9 Fuel pump, safc, and 650's at 15psi
thank you,
mark

 

[da_reeseboy]

650cc injectors flow 30%-33% more fuel than stock (450cc) injectors.
Did you disconnect the battery before working on your car? If not, its definately a boost leak.

- Jesse

 

[MarkAngelo05]

i did disconnect the battery... Well, I just did a boost leak test. I blocked off the upper intercooler pipe before the Throttle body, and pumped air into the compressor inlet... Well, I pressurized it to about 15psi, but while doing so, all I heard was a WOOOSH of air... coming from behind the compressor housing... I put my fingers behind the compressor housing and yup... I feel and hear air going through there... Once I start letting air in, the pressure just drops all most right away, and completely dissapates... I talked to the place that made the turbo and they said that it may just be a kinked or pinched O-Ring.... so I gotta take the turbo off the car and ship it off to them....

Mark

 

[da_reeseboy]

Sorry to hear that . Hope they get it back to you quick.

- Jesse

 

[fwdeclipse]

Why dont you just have them send you a new o ring and take your compressor housing off and put the new on in.Its easy just a big c clip to get off.

 

[MarkAngelo05]

you think i can do that with the turbo still on the car?

Mark

 

[fwdeclipse]

I dont know if you will be able to do it still on the car because that c-clip is a kind of a PITA and it would be pretty hard to get a good angle on it with it on the car.But even if you take it off you can just do it yourself and not have to hassle with packing it up and shipping it back to them.

 

[Soup Can]

hehe I feel your pain I'm having to do the exact same thing myself this weekend...ordered the o-ring from machv, thought I've been told a 7.4L diesel oil filter had the same size...at any rate it can be done on the car but it is a huge hug PITA...to get the snap ring pliers in there correrctly you get dangerously close to the radiator....I have my ring clocked a little higher on the turbo and I still am probably goign to just take the turbo off...the only bad part is getting the hard banjo oil line back on...you'd think since this is my 5th time i would of bought steel braided lines now to make my life easier...oh when you do put everything back together put a thin coat of oil on the oring, just to make sure it doesn't bind up on install...i think thats what happened to mine...

 

[MarkAngelo05]

Well, I got it all fixed up instead of sending it back to the shop. It still has a minor leak, which I think is due to the small space between the turbo shaft and bearings... I can hear a small Hiss.. but it holds pressure now. Thanks for the help everyone! and my sputtering problem was because I was running a lil too rich.. I got my palm pilot, but the rechargable battery in it was shot... mann this sux.. thanks!

Mark