o2/downpipe leak... could it cause a studder?

[turbo98eclipse]

Hey guys! i remember posting about this issue months and months back, but never finding a solution. I got some new advice/clues to what could be wrong today and wanted to run it by you.

To refresh you on the problem:

The car boggs. Actually, more of a stutter. At maybe 2500 rpms (light on the gas) everything is smooth. Go wot from there and the bogging begins. The higher the rpm when I start wot the less bogging there is. Listening to it, it sound like rapid puffs of air pumping through the back of the exhaust.

Now, the bogging only begun when I installed a new turboback exhaust. I THOUGHT everything was tight. But using seafoam revealed I had a leak someplace under the exhaust manifold (o2 housing area) Then I remember...I dont think I replaced the gasket between the o2 and the downpipe! Even with the downpipe bolted tight to the o2, having no gasket would allow a leak (duh)..

To make a long question short... Would a leak between the o2 housing and the downpipe be significant enough to make the car hesitate?

thanx for any help!

 

[diablos991]

You should try a boost leak test.

That gasket is cheap and easy to replace so you might as well fix that too.

 

[Tri-Edge]

This is what my car was doing today, and finally my lower IC pipe popped off since it was not on tight...also found my BOV flange bolts were loose....
Havent test drove it since cause its been pouring rain BUT I didnt have these symptoms before that pipe was loose, and it seems like you explained exactly the same problem...
will let you know if fixin my boost leaks helped...maybe your in same boat....
Fixed my boost leaks, and it still sputters as you explained...