eclemson

I had Misfire codes on cylinder 3 and 6 as well with my 01 996TT, particularly when starting from cold. After reading various forum suggestions, including replacing the pricey MAF sensor, I decided to remove and spray it with some sensor cleaner that I have in the garage locker. So far no more codes, and the motor starts and runs smooth. Time was about 15minutes, and cost about 10 cents. Seeing as the sensor has no wearable parts, and is fairly well protected from the elements, I had doubts that it needed to be replaced. Something worth noting, is that I had the airbox removed (which contains the MAF sensor) sitting on my garage floor for almost 2 weeks while I was doing a separate, more involved job on the engine. I imagine a bit of dust or other impurities worked its way onto the sensor, causing it to produce incorrect signals. Strangely enough, I have been dealing with similar misfire codes on my '98 Volvo T5 for over a year now, and had addressed everything I could think of that might be causing them (new plugs, wires, rotor, distributor cap, coil, etc.). I sprayed that MAF sensor at the same time as the 996, and so far, so good. From what I can recall, the same codes began to occur on the Volvo soon after I had done a bunch of upgrades on the intake, including removing the airbox for some time as well. I imagine that it doesn't take much dirt to cause an issue with these sensors. I would suggest cleaning the sensor (super easy) any time that the airbox is removed. Both cars are European turbos from the same generation, and both use Bosch ignition systems and components to my knowledge. For those of us with annoying and difficult to explain misfire codes, this is certainly a first step worth trying, and is way easier and cheaper than starting to replace other components. It has only been 5 days since I did this to both cars, but so far, so good, and they are both running like champs. Eric