too lean means you got too much oxygen and not enough gas going through your system. the cause is obviously the CAI. contact whoever you got that tune from and make sure you got the right one. and no disconnecting your negative terminal will not do any good, not on spanish oak at least, it will just reset your check engine light for a little while, which will come back on soon. just make sure you got the right tune and if they claim it is the right one then have them adjust the air/fuel ratio on it.

 

Thank you all for the input. I have not had any work done on the pipes yet. (That will be next week.:-) )I can adjust the WOT A/F ratio, and I set it to 6% richer today. The car seemed tostart pulling a bitharder in the low end with this setting, but after about 10 miles, the TOO LEAN codes returned. This is after getting a new tune installed by MMR, and then editing it. It must be the CAI that's giving me the codes as well, as they only started appearing after installation. One of the guys there told me that the S197's are so sensitive now, that that may be the problem. He said the same CAI installed on the 01's-04's don't bring up the CHECK ENGINE light. At this point, do I make them supply me another tune again, or is it possible to just ignore the damn light? Again, thanks for the info. :-)
-Mark

 

you cant ignore a CEL....they come up for a reason. Get a new tune...hell its a $75 fix by called brenspeed or b ama