P0101: replace MAF???
Thread Starter
Junior Member
Joined: Jul 2014
Posts: 63
Likes: 0
From: Los Angeles, CA
2001 ml320, 2002 c240
P0101: replace MAF???
Hello all:
I was driving my '02 C240 when all of a sudden, while coming to a stop, the car had some hesitation, stalled and the CEL came on. I was able to start the car again right away. When I came to another stop at the next traffic light, it was shaking and was about to stall again, I shifted to N and step on the gas so it wouldn't stall. Needless to say, I was able to drive it home with some hesitation, especially when accelerating from a stand still.
Plugged the scanner and got a P0101 code.
After searching the threads, I found several posts re this issue and DIY on MAF cleaning. The whole intake was pretty dirty with oil and dirt. I disassembled and cleaned the whole Air Filter Housing, MAF and connection (sprayed with CRC MAF cleaner), elbow and throttle body (with CRC throttle body cleaner). I put in a new air filter and replaced the two seal rings. Everything went smooth, put everything back then test drove the car. NO hesitation or stalling… until last Monday.
The car was just parked over the weekend. When I started it, the CEL immediately went on while it's trying to start. The initial crank was weak (sounded like a misfire) for about a second, then continued on to crank and started. Drove it, no stalling, or shaking or jerking when coming to a stop. But, when accelerating from a standstill though, (traffic light or otherwise) there's a 1-2 second hesitation before it takes off. I find myself pressing the throttle more than usual. After the initial hesitation, the car drives fine until I come to a complete stop again.
I deleted the code, only to come back the next time I start the car. (2x)
So at the moment, the CEL is still on with the same P0101 code. I was looking for any other suggestion you guys might have on what's the next thing to do/check (besides replacing the MAF, as my last resort). I plan to go back under the hood and check all the connections and possibly change the breather hoses (4) if needed. Is it a good idea to clean the MAF(wires inside) with earbuds soaked with CRC cleaner?
Thanks!
Parts I've ordered and replaced:
# 1120940604 Air filter
# 1121590080 Air Boot Seal Ring
# 1121590180 Air Intake Seal
I was driving my '02 C240 when all of a sudden, while coming to a stop, the car had some hesitation, stalled and the CEL came on. I was able to start the car again right away. When I came to another stop at the next traffic light, it was shaking and was about to stall again, I shifted to N and step on the gas so it wouldn't stall. Needless to say, I was able to drive it home with some hesitation, especially when accelerating from a stand still.
Plugged the scanner and got a P0101 code.
After searching the threads, I found several posts re this issue and DIY on MAF cleaning. The whole intake was pretty dirty with oil and dirt. I disassembled and cleaned the whole Air Filter Housing, MAF and connection (sprayed with CRC MAF cleaner), elbow and throttle body (with CRC throttle body cleaner). I put in a new air filter and replaced the two seal rings. Everything went smooth, put everything back then test drove the car. NO hesitation or stalling… until last Monday.
The car was just parked over the weekend. When I started it, the CEL immediately went on while it's trying to start. The initial crank was weak (sounded like a misfire) for about a second, then continued on to crank and started. Drove it, no stalling, or shaking or jerking when coming to a stop. But, when accelerating from a standstill though, (traffic light or otherwise) there's a 1-2 second hesitation before it takes off. I find myself pressing the throttle more than usual. After the initial hesitation, the car drives fine until I come to a complete stop again.
I deleted the code, only to come back the next time I start the car. (2x)
So at the moment, the CEL is still on with the same P0101 code. I was looking for any other suggestion you guys might have on what's the next thing to do/check (besides replacing the MAF, as my last resort). I plan to go back under the hood and check all the connections and possibly change the breather hoses (4) if needed. Is it a good idea to clean the MAF(wires inside) with earbuds soaked with CRC cleaner?
Thanks!
Parts I've ordered and replaced:
# 1120940604 Air filter
# 1121590080 Air Boot Seal Ring
# 1121590180 Air Intake Seal
Member
Joined: Nov 2007
Posts: 171
Likes: 1
From: ontario, Canada
C230 COUPE 2003 M271
if you havent done this yet, always disconnect battery for 10mins to clear the fuel trim map learned values. then unplug the maf and see if the car drives normally. If the maf was indeed giving faulty readings this will cause the engine to use the default factory estimate of what the air flow should be without using the maf itself and the car should run normally (but throwing the maf code of course) if it still runs bad you have another problem. look for vacuum leaks would be the next step then imo.
dont replace the maf unless you are sure. it is damn expensive for such a small part!
dont replace the maf unless you are sure. it is damn expensive for such a small part!
Thread Starter
Junior Member
Joined: Jul 2014
Posts: 63
Likes: 0
From: Los Angeles, CA
2001 ml320, 2002 c240
Thanks wvadam. I was wondering, I'm scouring through the threads and came across resetting the throttle. Is that also something I should consider before or after your suggestion?
I'm planning on unplugging the MAF after disconnecting the battery as you've suggested.
Thanks!
I'm planning on unplugging the MAF after disconnecting the battery as you've suggested.
Thanks!
Member
Joined: Nov 2007
Posts: 171
Likes: 1
From: ontario, Canada
C230 COUPE 2003 M271
try the throttle reset first if you like. from what i have been hearing around here it sounds like that may help with the 1-2 second delay when you are accelerating but as far as the shaking that really sounds like a vacuum leak. those breather hoses are a known problem on a lot of cars esp with this age. if they havent been done you should do them anyways to rule them out.
