Hi,
Just had my car tuned recently on 91 pump gas. The idle is now at 12.0-12.5 afr. WOT is around 10.0-10.5, and cruise is 14.0-14.5 afr. Is this ok? Just wanted to get some opinions before i head back to the tuner. Thanks!!

 

No, get it retuned.

 

Could you elaborate on it? You think my afr for WOT and cruise are pretty spot on? Would I be risking my motor if it idles at 12.0-12.5?

 

To rich all over. AFR at idle whenever possible should be 14.7

Full boost about 11.5 AFR on gasoline. As long as im around 11.0-11.5 im happy.

For Spool 12.8-13.5

For E85 11.8-12.0 WOT, same for spool as gasoline.

Idling at 12.0-12.5 is washing the cylinders out, so i would try to avoid it if possible.

 

Most likely, it's a bad O2 sensor
or
MAF sensor needs to be cleaned or replaced
or
bad injector calibration in case you have installed larger injectors.

 

Sorry for jacking the thread, but I was about to post about AFR values. I usually tune fuel within the same range as mentioned above. But a few days ago I had to tune a 2.3L Evo with 272 cams & ported head, the turbo is an E9 70 series, phenomenal spool, hitting full boost of 29psi (320 load) at 3800 RPM, I was reluctant to enrich AFR to 11-11.5 at such low RPM, as a compromise I set AFR at 11.9-11.8 at full boost going down to 11.4 by red line.

What do you think?

 

your ECU should be adjusting to 14.7 while in closed loop. weird that idle is more rich than cruising, though. i don't know enough about tuning to guess why that would be.

 

you as the tuner should decide on what the car wants. do keep in mind not all widebands or sensors are created equal. as the life span of the sensor shortens, they read leaner. What might be 12 AFR on one car, can be 11 AFR on another car.