CEL P219a after Perrin Inlet and Drop-In Filter
 

**Disclaimer** I tried searching on the forum and Google. Didn't find this series of events but Found some helpful info about how to read data logs. And have had the OFT diagnostics up and everything "seemed" okay from what I could catch.

Threw code P219A today:

Okay ladies and gents here's the Low down. Been running OFT Stage 2 with Gruppe-S UEL, JDL ultra quiet highflow front pipe, and Corsa Catback for about 3 months.

Just added Perrin Inlet tube and a freshly oiled K&N air filter. 300miles later threw CEL P219A: Bank 1 Air Fuel-Ratio Imbalance.

Checked the sensor, and seals, everything looks to be good. Anyone run into this, or have some suggestions? I have a 3rd gear/4th gear pull recorded but won't be able to load it until Sunday most likely.

P219A is AFR imbalance ie the ecu is not getting the afr its askiung for.

check your long term fuel trims LTFT with your oft

also log AFR and Commanded AFR

ltft should be below about 8%

afr and commanded afr should follow each other fairly well during accereration

you likely have air leak or over oiled filer and oil got on maf sensor. you can get maf cleaner from auto shop

or you have developed an exhaust leak near or before o2 sensors, did you use new gaskets on header

Steve thanks for the quick response!

I replaced the gaskets all around. Checked for exhaust leaks by way of having someone cover exhaust and didn't see any leaks (I realize it's not the most effective way)

Ltft fluctuates between -2.34/-3.12

AFR and Command AFR seem to follow almost identically. Parameters based on another thread seem about right. However at wot it does read11.25:1

My buddy next door said I may have over oiled as well, but it didn't "appear" to be over oiled.

man, skip the oiled filter and get yourself a good dry flow filter instead. never have to worry about over oiling and still get the same small HP gains.

And just like that, 300 miles later, it's off...

My LTFT is at 17.18. Is that bad?

So, did you clean the MAF like @steve99 suggested ....??


humfrz

17% does not sound good


you have either changed intake and not re-scaled maf


got dirty/oily or defective maf sensor


defective front 02 sensor


intake leak


exhaust leak


running incorrect tune for fuel used ie E85 on petrol tune or petrol on E85 tune

I'm having this problem as well, Fuel trims and AFR look normal. Mine CEL just randomly popped up after a year of having OFT STG 2 with Tomei UEL. I get codes p219a and p119e. I had stock air filter and changed it to K&N after CEL popped up and tried cleaning MAF sensor, but still no luck.

Check for intake and exhaust air leaks

and just like that it's gone... I did not do anything lol