All: I am a relatively new poster, but I have problem that I cannot get to the bottom of. Over the weekend, I recharged my K&N filter (I know, probably my first mistake) and replaced it. The car (2000 a6q - 2.7T) ran fine Saturday night and all morning Sunday.

Sunday morning I drove all over town, on the highway mostly. After getting back to my house, I pulled into the garage and the car began to misfire terribly. I was worried that it was going to stall, although it never did. I went to AZ and pulled the codes - P1423 and misfire on cylinder 5. After researching the issue, I checked all vacuum hoses and all seemed secure. I unplugged the SAIP to reset the code. After plugging it back in, the misfire was corrected (it is still running very rough), but the SAIP was not working when it is started.

To this point, I am going to try to clean the MAF tonight, though, I don't think this is the problem (I have disconnected it to see if that would resolve the problem, but it did not). I have checked all the fuses, none are blown. The SAIP is not working when I turn the car on.

My guess is that this problem has something to do with the K&N filter, but I don't know how. I can't see anything that would allow the recharge oil to get into the SAIP. So, maybe they are unrelated and it's just a coincidence. Just seems unlikely. Any one have any other thoughts?

 

common problem with K&N filter oil - too much screws up the MAF

 

Checked the MAF and it's not the problem. Any other suggestions?

 

Other than looking for more vacum leaks --
I'd see what codes are there now--
The AZ code reader is somewhat OK but you really need to get VagCOM to see Audi specific codes.