K&N CAI Issue

Hey guys I had the K&N CAI installed for only 3 days and had P1128 & P1130 CEL come on twice. I decided to return the product and go back to stock. After 5 days of stock I received another CEL P1130. I take off the throtlle boot and find oil on the butterfly. I believe this is from K&N CAI and this is what caused my CEL. I am not sure what to do: -Clean throttle body -Clean MAF -Reset code Then if CEL comes back: -Buy new MAF

I am not sure about the Porsche kit, but from my experience (import auto tuner) K&N's come from factory with a RED coloured mineral oil. If I am correct and your filter came preoiled in a red colour you might want to try checking for other culprits of that oil. Also the K&N oil is harmless to your motor. Hope this helps

I just read a few more threads and it looks like yours is not an isolated issue. I guess you learn something new everyday (such as me and K&N not using only red oil).

Yeah...would agree...I have used various K&N filters/kits on various cars. I have even used the recharge kit. The oil is red...and usually even if some gets in...never is a problem. I would check the crankcase ventilation (PVC?) valve/tube...usually engine blowby is responsible for oil coming from the crankcase into the intake tract. Not sure if P-cars have this...but others do. Besides, what is P1128 and P1130 pointing to? One common problem as well is air getting in past the MAF..it's unmetered and causes the car to act weird...depending on the volume of air coming in. thanks, Amir

True, I still use my old red dye K&N recharge kit from my JWT Cone intakes on my 996 EVO intake.

Guys, thanks for your feedback. It is funny that after 2 yrs of ownership never seen this oil in throttle body until removing K&N intake. 1)Local mechanic stated it looks like the K&N oil 2)Is that oil to clean to come from crankshaft? Thanks!

Buy a new MAF, sell your k@n HAI on ebay to some other sucker. Even if you don't oil the filter, dirt will enter the filter and re-damage your MAF and possibly your engine. Then clear fault and be happy with your car.

From what I've seen on the board I wouldn't touch a K&N with a ten foot pole.

go with stock air box and K&N flat panel filter... this works well and doesn't require frequent cleaning...

There are 2 sensors on the MAF; temperature and airflow. The MAF is fed with a 5 volt supply. Once sensor is a thermistor to measure the temperature of the incoming air. This measurement is in the form of current which changes as it gets hot or colder. The amount of current in translated into temperature by the DME which uses this info to control various settings, such as fuel and timing. The airflow sensor is a wire( foil), also fed by a 5 volt supply, which generates a frequency to the DME based on air flowing over it. The sensor consists of a wire that the DME maintains at a specific temperature at all times. As air passes by this wire, it cools the wire and the computer has to increase the frequency to the wire in order to maintain the predetermined temperature. This increase in frequency is translated into airflow (volume) by the computer. Therefore, now the computer knows how much air is passing into the intake and what its temperature is. Using this information, it can determine how much fuel is necessary to inject. Typically, when oil or other contaminant gets on the airflow wire, the air that passes by it does not have as great a cooling effect as it would if the wire was clean. Therefore, the amount of current generated by the computer to maintain the wire�s predetermined temperature is not as great, and the amount of frequency passed to the computer is less than the actual airflow. This causes the computer to inject less fuel into the engine than it should�.creating a lean condition. If the difference is great enough, the O2 sensors will not be able to richen the mixture out enough before they go outside their voltage range and will generate an error code. Under normal circumstances, the LTFT should take up the slack in fuel/air ratio that a miscalibrated MAF produces which will allow the O2 sensors to operate properly within their range. LTFT and O2 sensors are ignored at WOT. Air passing over the MAF that is too turbulent can affect the airflow readings unpredictably. It can sometimes show high reading and low readings. I have performed tests that concluded that simply changing the position of the MAF in its mounting bracket by only 1% could drastically affect the amount of airflow that is recorded. It is imperative that this sensor be installed so it is directly facing into the flow of air. Otherwise, you may get O2 sensor generated CEL�s. Some after market intakes are not lined up properly and simply removing and reinstalling the sensor can make errors disappear or to be generated.

generally oil coated mafs cause the car to run rich, i havent doen testing but p-cars come in running rich 99% its a ouled or failed maf

whoa...excellent post man...I think I have a much better understanding of what could have happened in my case...thanks!!

MAF's measure Mass (lbs/sec) Flow not Volumetric (cubic ft/sec.) flow. Mass flow is Volumetric flow compensated for temperature and pressure. Hence the name "Mass Air Flow". Volumetric flow for any given RPM will always be the same, as the engine is a positive displacement pump and the volume of air is always directly related to the engine displacement and rpm, will not change with any changes in temperature or pressure.

If you wasnt to be technical, the MAF measures nothing but current and resitance. It does not measure pressure, buy calculates pressure from the IAT. Any inaccurate reading in the IAT or hot wire/film, all calaculations will be incorrect. If you IAT is reading too low, then your engine will run richer and your timing will be advanced.

Please explain how it calculates ambient pressure.

It's is calculated on an assumed atmospheric pressure since the car does not have a MAP sensor. It uses this assumed figure alongs with IAT and air volume to determine density. Calculated load is also part of the calculation. Differences while in closed loop are corrected by O2 sensors. At WOT, not adjustment is automatically made and your F/A mixture will likely be incorrect.