Running WAY too rich, how to correct?

[jas142]

I have an o/r UPR X pipe and K&N on my 04 Mustang GT Automagic. I replaced the rear o2 sensors when I put them on (we damaged them taking off the old X pipe) and the Mil Eliminators are in and working (no CEL)

But the car runs VERY rich, and I'm getting very bad gas mileage. How could I lean this out and correct it to run a better ratio and hopefully improve my gas mileage? Would a Diablo Chip help?

 

[DBMSTNG]

you could get the car reprogrammed, or just give the ECU some time to adjust.

 

[jas142]

I've had the X pipe on for about a month now, and I tried resetting ECU as well. Didn't fix the problem.

I'm afraid to take it to the dealership to get it reflashed because then they'll know I modified the car and void my warranty.

 

[mrvax]

You can remove the EEC and send it with dyno runs to Tim at T&J Performance. Contact "Cobra Killer". Or, you can get a custom chip and dyno tune which will cost about 2x as much.

 

[PDubs]

Dealerships generally do not work on cars with o/r pipes. You could get a tuning module or get some mods to flow more air in there.