CEL comes and goes, P1123 & P1125 Lean Limit. Is Airflow Sensor

[Wonko The Sane]

Good list, Ed.. see if my thinking is logical for each one:

MAF sensor - This is what I'm leaning towards, I think it makes the most sense by process of elimination.
vacuum leak - Would this be intermittent?
low efficiency cat - The code says "range 1", which I'm assuming is talking about the oxygen sensors before the cats, so I wouldn't think that would affect it..
low efficiency oxygen sensor - Shouldn't be. All 4 sensors are less than 7k old, and this CEL shows up for both banks, it would only come up with cylinders 1-3 or 4-6 if it were one failing sensor, not both sides I would think
problems with wiring to sensors - Again, I think it would only throw a code for one side, not both.

I dont like those stinken CEL lights - I hate these buggers, too! I think everyone does

[edevlin]

I would also suspect the MAF because of the intermitent nature of the CEL.

Ed

[NickCats]

Wonko,

I would suggest cleaning the MAF. Worked for me :

My First CEL

Dude, I cleaned my MAF !

Nick

[Wonko The Sane]

Thanks for the suggestion, NickCat! I did already clean it once, and it's still doing it, so I'm thinking new MAF time...