I recently installed delete plates and had my tuner adjust my tune accordingly.

Ever since, I have been having strange idle issues.

1: When i turn on the A/C, the idle will surge to 1k, settle to 600, then drop to 400 like its gonna die and then surge back up to 1k. Rinse and repeat.

2: While driving, if I put the car in neutral and coast, rpms will drop and remain at 400rpms until i come to a complete stop, then will surge back up to 800 or so.

I've ran data logs and see the o2 sensor voltage going all over the place and have sent the data logs to my tuner but so far they appear to be stumped. They sent me and adjusted tune but that just made the problem more prevalent. They requested I clean the throttle body, which i did during the CMDP install. Lastly they just requested i 'clock' the MAF 90*. I did that and just as I thought, no change.

Anyone else have this issue after installing CMDP's. Is it a mechanical problem or a tuning problem?

 

Who's your tune through? I had the same problem after installing my CAI. After lots of time spent trying to figure out what was going on I turned to Doug at Bama who finally was able to write a tune that solved the problem.

 

I had the same issue after my CAI problem as well.. It seemed to sort of work itself out over a day or so though..

 

I would have your tune rechecked, i have a similar problem when i added long tube headers awhile ago that was fixed with a dyno tune. Get that thing on a dyno and fine tune it.

 

update:

I wanted to keep everyone updated on my issue.

My tuner suggested loading my original tune from 2 years ago that was pretty much a canned intake/exhaust tune to see if the problem still shows up. I did and the idle issue is gone. So its not a mechanical issue but indeed a tuning issue.

He is supposed to send me an updated tune today.

 

Good to know. Are you switching tuners now or going to someone new? I'd suggest talking to chris at TILLMANS SPEED. Excellent tuner.

 

Good luck let us know how it turns out.