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yet another ign correction post

Oregon city
so my 2014 fiesta st has 60k miles with a muffler and res delete. I have been running stage 1 cobb ots for at least 15k. regular maintenance oil changes at 3k and all. yesterday morning I was running a little late and ran it cold. Not hard mind you i stayed out of boost but below 2k it registered negative 1 for corrections on all cylinders. Afterwards it has been running heavy negative corrections on all cylinders whenever I hit boost. I thought fuel might be an issue so I dumped it down to the stock tune. Still negative corrections. I pulled the plugs and they look fine. Reset the ecu and still having issues. Anyone have any ideas what might be going wrong? thank you for your help.


Active member
Cleveland, OH, USA
will try a gallon of e85 tomorrow. Any ideas on repercussions if this continues?
I second the idea to put a gallon or two of E85 and see if that cures it. If that doesn't work I'd wonder if something is triggering the knock sensor, like a vibration or a rattle (I vaguely remember someone saying certain RMMs can trigger knock sensor??)

Also FWIW I ran Cobb OTS tunes for a little while but I noticed it tended to get neg corrections. Ive switched to Dizzy tunes and they are more smooth, more power, and less negative corrections. Highly recommend.

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