[suby6]

It's subtle and never noticed it until doing a header and getting a tune. Seems like when I am decelerating while engine breaking or limiting speed down a hill the car is a bit jerky. Its like it has less resistance for a split second repeatedly.

Engine mout wear? Doesn't clunk while shifting or anything...

Exhaust scavenging?

Anyone else noticed this after exhaust / tune?

Could it be the IAC? It's never been cleaned.... keep meaning to..

 

[suby6]

bump

 

[BC_ZX3]

Anyone else noticed this after exhaust / tune?

Could it be the IAC? It's never been cleaned.... keep meaning to..

Can't say I've noticed that. (I have both exhaust and a tune.) Doubt it's the IAC unless you're also having idle problems at a standstill. If you loaded a tune, can't you do some data logging with your flasher?

 

[suby6]

Can't say I've noticed that. (I have both exhaust and a tune.) Doubt it's the IAC unless you're also having idle problems at a standstill. If you loaded a tune, can't you do some data logging with your flasher?

Yeah I will try that. Not sure what I would be looking for. Will it warn me of potential trouble spots or just give a bunch of info that means nothing to someone not experienced with this?

 

[BC_ZX3]

Now that I think about it a quick and dirty test would be to restore your stock tune and see if the problem goes away. If it does, it's your tune. In that case, your tuner could direct you on what to log in order to resolve any problem. If you still have the problem using your stock tune, then it's obviously something else.
Type of header fitted?

 

[suby6]

Hey thats a great idea! Will do that 1st.

Header is just an OBX POS.

The SRI is a MAC brand. Randy wasn't too sure about tuning around that as he didn't have specs. Was thinking it could be a tad off cause of the intake. He says he doesn't change any deceleration parameters though so it shouldn't be the cause. Switching back to the stock tune will definitely test that..

Should clean the IAC as well though as last summer I had a bit of a stalling issue when coming to a stop. Idle does still sometimes drop a bit low momentarily when stopping at lights but no stalling anymore. Mind you now that I think of it the stalling was from an EGR leak.