Diagnosing A/F , possible exhaust leak?

[Nemesis]

Under full load im running 12.8:1, and under Nitrous Im running 11.5:1. However, at idle its around 15.6:1, which is not close to stoich. However, I think I might have a very minute exhaust leak. Could this be causing the problem under very light load situations and cruise?

[green91]

alot of cars dont idle at 14.7:1. ive seen a crx HF that idled closer to 18:1. i wouldnt be terribly concerned.

[Spyder]

cars run rich at idle, especially when they are cold it helps them warm up.. is that according to a nice highly accurate wide band.. or is that according to a light show aka air to fuel ratio gauge?

[green91]

15.6:1 is not rich! actually, most cars run slightly lean under cold conditions.. lean = warmer egts.

[Spyder]

15.6:1 is not rich! actually, most cars run slightly lean under cold conditions.. lean = warmer egts.

correct, sorry i had them backwards.. i realized it while i was eating dinner and came back to check this post and edit it :o

[Nemesis]

cars run rich at idle, especially when they are cold it helps them warm up.. is that according to a nice highly accurate wide band.. or is that according to a light show aka air to fuel ratio gauge?


All data was taken from an LM-1. Its impossible to obtain a steady reading from a narrow b. All of my readings are taken from the sensor position where BATLGround welded a bung on. I have no main cat and I have MSDS Headers which remove the precats, so Im getting a good clean EG reading

Thanks for the replies everyone.