I was reading up on different intakes and air filters and such for our cars, and I stumbled upon quite a few threads of people having low end throttle response problems. Their cars weren't responding at low rpms like they should. There was one common modification most of them had. They all ran air filters, be it foam or paper, that had dirt trapping oil on them from the factory. A lot of times, these filters come oil-soaked, and when they are installed, some of the excess oil gets sucked upstream and coats the MAF sensor. Since the MAF sensor is such a delicate and important tool used for measuring air, if it is dirty or is coated with oil, it will not be able to do its job effectively.
I also run an ITG filter that came oiled. I have been having low end throttle response problems for as long as I can remember. I have tried to blame these problems on my tuning (UTEC), boost control being too slow(UTEC) so I tried an MBC, intercooler heat soak, intake not pulling in enough air at low speeds, and maybe even the Walbro fuel pump I have. Some of these are way out there, I know. But when I start to have a potential problem, I do sit around and think of every variable that could effect my car.
So this last Thursday, after I was done reading about how a MAF sensor could become dirty, I tried to fix the problem. I took out the MAF on my car and attemted to clean it. This is how I did it:
Take the MAF out of the car and make sure not to touch any of the sensors with your fingers.
Get a plastic sandwhich bag and spray non-chlorinated brake cleaner into it. Enough to cover the sensor portion of the MAF.
Put the MAF into the bag and shake it around.
Take out the MAF and let it air dry.
Re-install it after it is visually dry.
The next morning I started up the car and the car seemed to idle even better than it did before. The low end throttle response was back and the car runs strong now from idle to redline. Mid range throttle reponse was also helped out.
If you run an air filter that came with dirt trapping oil on it, try this MAF cleaning trick. Your car may run a little better than it did before. It worked for me.