vbrock1137
06-09-2006, 07:57 PM
First, I searched for quite awhile on every keyword I could think of that would relate to my situation, and I found some useful info, but I'm still not sure what to do.
Here's the story: A couple of months ago my car starts to hesitate when accelerating from a stop. This develops into a sputter/misfire that occurs at parking speeds as well as when accel. from a stop. My local dealer tells me it's a misfire on cyl. 4 probably caused by water in the gas, so they drain the tank and add a fuel treatment to the new tank of gas.
Car ran great for a couple weeks at the most. Then the problem returned, but worse. It would always sputter like before, but occasionally the problem would not go away at higher RPM like it did earlier, it would misfire until I restarted the car (this sounds like limp mode...?). At this time my transmission decides that it doesn't need 4th gear anymore, so I take the car back to the dealer and several thousand dollars later I have a new transmission. While it was there they got the cyl. 4 misfire code again and replaced the coil, plug and plug wire.
Again, the car ran great for a couple of weeks, but now the problem has returned just as bad as before. I'm hoping it's not the wiring harness or something else terribly expensive. I'm reluctant to take the car back to the dealership as I've already paid them almost the value of the car over the last couple months.
What puzzles me is why this problem disappears every time I take my car to the dealership. The sputtering problem is pretty consistant otherwise. It happens at least 75% of the time I accelerate from a stop, but that 25% that it accelerates smoothly is pretty random; NEVER has the misfire gone away for days at a time other than when I've gotten it back from the delearship.
Anyway, does this sound like a MAS problem? Someone in a previous thread said that the MAS runs closed loop at low RPMs and open loop at high RPMs... this would explain why I have no problems at higher RPMs. Is there anything I can do to test the MAS before I shell out the money for a new one? Also, I've seen a few people mention cleaning it, but I couldn't find a specific method. Any suggestions?
Also, I have a relatively new paper filter... I've never had a K&N that could have gotten oil on the MAS. Additionaly, the MAS was replaced apx. 20,000 miles ago.
Here's the story: A couple of months ago my car starts to hesitate when accelerating from a stop. This develops into a sputter/misfire that occurs at parking speeds as well as when accel. from a stop. My local dealer tells me it's a misfire on cyl. 4 probably caused by water in the gas, so they drain the tank and add a fuel treatment to the new tank of gas.
Car ran great for a couple weeks at the most. Then the problem returned, but worse. It would always sputter like before, but occasionally the problem would not go away at higher RPM like it did earlier, it would misfire until I restarted the car (this sounds like limp mode...?). At this time my transmission decides that it doesn't need 4th gear anymore, so I take the car back to the dealer and several thousand dollars later I have a new transmission. While it was there they got the cyl. 4 misfire code again and replaced the coil, plug and plug wire.
Again, the car ran great for a couple of weeks, but now the problem has returned just as bad as before. I'm hoping it's not the wiring harness or something else terribly expensive. I'm reluctant to take the car back to the dealership as I've already paid them almost the value of the car over the last couple months.
What puzzles me is why this problem disappears every time I take my car to the dealership. The sputtering problem is pretty consistant otherwise. It happens at least 75% of the time I accelerate from a stop, but that 25% that it accelerates smoothly is pretty random; NEVER has the misfire gone away for days at a time other than when I've gotten it back from the delearship.
Anyway, does this sound like a MAS problem? Someone in a previous thread said that the MAS runs closed loop at low RPMs and open loop at high RPMs... this would explain why I have no problems at higher RPMs. Is there anything I can do to test the MAS before I shell out the money for a new one? Also, I've seen a few people mention cleaning it, but I couldn't find a specific method. Any suggestions?
Also, I have a relatively new paper filter... I've never had a K&N that could have gotten oil on the MAS. Additionaly, the MAS was replaced apx. 20,000 miles ago.