Hey guys, Iv been ahving a problem with my new blazer. At 3500km I blew an o2 sensor...no biggie....under warranty....they talked **** at the delaer**** about the exhaust, Cat back with a Flowmaster, and tried to tell me it was the mufflers fault...meanwhile it was the o2 on the left bank of the manifold down pipe...stupidff...but it got fixed...now my light is on again..says its running Lean in Left and Right banks...I put a k&N intake on it liek a week ago...but that shouldnt effect o2 sensors...also the light seems to be commign on only when it gets really cold........gonna take it to the dealership,but seeing everyonmes insight...cause i KNOW they will hassle me about the Intake or muffler again!!!

Thanks

 

My advice is to ditch the K&N filter and CAREFULLY clean your MAF before you go ANYWHERE near a dealership. You can put the filter back in afterwords, but just get it out of there before going to the dealership.

GM pretty much has a standing policy to do NO warranty work on engines or transmissions in vehicles that have a K&N filter or any aftermarket oiled air filter for that matter. The problem is that the MAF sensor can get coated with the oil from the filter and pick up dirt that gets through the filter (no filter is 100% efficient at removing dirt). The readings from the MAF control a lot of crap and can actually cause the transmission to slip a bit, wearing the clutches and causing a host of drivability concerns.