Yesterday, I was reving my engine to 7,000 rpms and then I proceeded ahead. When I started to move, I started to here some very loud exhaust noises from under the hood. I have a ichiba header with exh. wrap, so I naturally figured that it finally cracked. I went home and and took it off, sure thing, it had a minor crack at one of the two collectors. I replaced it with my ported stock manifold, buttoned everything down and started the car back up. The exh leak is still there. Is it possible that my turbo has an exh. leak? All the bolts to the head and to the turbo are snug. I can't figure it out. Could this be a spun bearing? Is this what a spun bearing sounds like? I slightly hear an exh. leak at idle, but even more when I press the accelerator down. I just don't get it.

Earlier yesterday I did a fuel system cleaning. I had some hesitation at times so I figured that this would clean that up. Could this have anything to do with what I'm going through right now?

Has anyone else had a problem like this?

2006 Lancer EVO IX MR
Upgraded turbo with TurboChargers.com 20G six blade wheel
Custom reflash on dynojet
3" TBE with cat delete
Injen intake and UICP
upgraded LICP
Greddy Spec II Boost controller set at max of 23 psi for 93 oct.

 

You launched at 7k??? Post a video with a sound clip, it should help others help you out on your problem.

Also why did you use fuel cleaner, I'm guessing an injector cleaner on your 06? It's practically a brand new car and the injectors wouldn't have any carbon build up that would be worth cleaning. The hesitation you mention might have been fouled plugs? did you check your plugs?

 

I didn't actually launch the car. I was just reving it up to make sure there was no misfiring. The first thing I checked was the plugs to see if they were the reason I had hesitation, but they were fine. I tried different gap settings as well (.030, .028, .025, .024), but there was no difference. The hesitation basically comes on right after boost comes on at about 10 psi, then goes away. I have 31,000 miles on the car, so I thought it would take care of it and it did! I'll try to post an audio clip as soon as I get home today.

I thought that if I replaced the manifold everything would be fine. It just sounds like there is a gapping hole in the manifold somewhere. I checked it before I put it in and there was no holes. The exh manifold gasket and manifold to turbo gaskets ahd no evidence of any exh leaking neither. It almost sounds like the turbo has a big hole in it on the exh turbine side.

 

for the exhaust leak i would reinstall the stock manifold with new gaskets. as for the misfiring/hesitation get some new spark plugs

 

I finally found the exh leak last night. After removing th eoem manifold for the second time, I noticed that my Invidia O2 housing was missing the lower bolt. It must have loosened up and just fell out. I removed the turbo and found two other loosened bolts, so I tightened them all th ebolts and replaced the missing one. I got it all back together at almost midnight, last night. Finally, oo exhaust leaks now!

I still have hesitation at times. I changed out my spark plugs with new OEM iridium plugs, but it still does it.

Symptom:
I let the car warm up and when I hit boost at about 10 psi, there is a slight miss-fire. After driving for awhile it goes away. I can't seem to figure this one out. Could it be the O2 sensors? I accidentally dinged the rear O2 sensor when I removed the stock cat, but I haven't had any check engine lights come on.

 

I finally found the exh leak last night. After removing the oem manifold for the second time, I noticed that my Invidia O2 housing was missing the lower bolt. It must have loosened up and just fell out. I removed the turbo and found two other loosened bolts, so I tightened them all th ebolts and replaced the missing one. I got it all back together at almost midnight, last night. Finally, oo exhaust leaks now!

I still have hesitation at times. I changed out my spark plugs with new OEM iridium plugs, but it still does it.

Symptom:
I let the car warm up and when I hit boost at about 10 psi, there is a slight miss-fire. After driving for awhile it goes away. I can't seem to figure this one out. Could it be the O2 sensors? I accidentally dinged the rear O2 sensor when I removed the stock cat, but I haven't had any check engine lights come on.