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Discussion Starter #1
Hey everyone new here. I picked up a 98 cobra a few weeks ago, and have been trying to get all the bugs out of it. It started out chasing a P0171 code. We discovered the IMRC's were deleted in the process, installed new IM gaskets, checked for vacuum leaks all good. It has a bama tuner that wasn't ever updated since new so I updated that. We cleaned the MAF also. Spark plugs look good.

After doing this it started idling like crap at start up, and when trying to give it gas, it backfires through the exhaust. It also started idling high around 1800 rpm, and when pushing the clutch in, the rpms raise further. Once the car warms up it stops backfiring. It pulls good, will chirp the tires when shifting etc. I adjusted the throttle adjustment screw and got the idle to drop down a bit, but it still raises when the clutch is engaged etc. We did a fuel pressure check and it was at 39.

Any ideas?
 

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Probably something to do with bama's **** tunes tbth... I'd contact a legit remote tuner... you couldn't pay me to run a bama tune on a car I actually cared about. Is it a PATS deleted tune you have btw? Returning it to stock means it might be a PATS issue with a no start condition.

Also this is the wrong forum to post Cobra stuff, that's the DOHC forum.
 

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Discussion Starter #4
I'm not sure, I don't think so. If I try to unlock the passenger side door first it sets the alarm off. I have an appointment on the 1st to take it to a shop that does dyno tuning.

Can a moderator move this to the correct forum?
 

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That's your best bet, have a good tuner unfuck whatever bama is doing on the tune and go from there. Get a wideband if you don't already have one. The shop will probably stick a wideband in one of the rear o2 bungs but its def good to have your own.
 

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Discussion Starter #6
Yeah I'll get one here, I think I have a spare in one of my moving boxes I could use but I haven't had time to look for it
 

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As far as RPMs go the tuner can also adjust the IAC but that would be somewhere to look if its still not idling right, IAC might be bad or even the wrong one. I had a 96-98 one on my 99 Cobra engine and that caused all kinds of issues before I realized it. You could also have a vac leak.

Good tuner will hopefully get it all sorted... with the IMRCs deleted I'd go 4.30s minimum out back if you haven't already.
 

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Discussion Starter #8
I'm not sure what it has gear wise, does seem to haul butt tho. I've been trying to figure out if the IAC is correct but can't find any solid info on if it is or not. It's just weird it didn't do that when I first got it. I smoke tested and put a vacuum gauge on and it seems to be sealed.
 
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