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Took it for another test ride and at one point pressed the gas pedal all the way to the kickdown and ... the car stalled immediately. Tried re-starting - the car would run for 2 seconds and shut down every single time. Had it towed to the dealer - they do it for "free" through MB roadside assistance. Dealer called and said that the MAF sensor is bad along with a problem/misfire with plugs and plug wires. My plugs are new by the way. Apparently they pulled code P2004 which is for a bad MAF. Funny thing is that I scanned the car while waiting for a tow and there were no stored codes at all. Anyway, they backed off the bad plugs and wires and said that they will replace the MAF only and if it does not fix the issue there is no charge. I know I can get a new sensor for around $200 and replace it in 5 minutes but I told them to go ahead and try the new MAF themselves. If I tried to take the car now they would probably charge me for the tow and troubleshooting anyway. I'll update what happens. I did spray the MAF with a CRC electronic contact cleaner while working on the CPS - but I doubt that would kill it?
well just did the CPS on my 2003 c240 4matic wagon
I did not remove the MAF I was able to just reach it from the drivers side I did it by feel as i could not see it I loosened the bolt with the socket then removed and reinstalled it by hand
Oldschool240, your PDF instructions were great. I just followed them and finished the job in about 4 hours, which included time to clean the MAF, retrieve several dropped items, and research MAF removal. The only improvement to the instructions would be to indicate that after removing the PCV hose, note that two clips hold the MAF to the intake manifold. Lift the top clip while tilting the top of the MAF toward the firewall. Then, disengage the bottom-left clip while pushing the entire MAF toward the firewall.
How difficult is it to replace the CPS on the SLK 230 roadster?
I bought a CPS but it looks a bit different then what I think is the CPS on my car. the plug that goes into the CPS on the car is round; the hole for the plug on the new part is not round. any ideas?
I just completed the CPK replacement using the instructions from the original poster. I was going to use OldSchoolC240's instructions, but I just did the same repair on a ML320 and it took 15 minutes. So I thought, why not try the fast way first. Anyway, I took some pictures and thought I'd share what I learned.
First you need to remove the engine cover.
Then, working from the drivers side, remove the E10 bolt which holds the electrical support bracket on:
Cut the wire tie which secures the bracket to the wiring harness, and remove it
The area shown is your working area. If you look close you can actually see the CPK sensor
Now reach your hand down in there and depress the latch on the plug and unplug the sensor. Pull it up through that hole so you can get it out of the way
Now is the tricky part. The bolt which holds the sensor in is located below the sensor (towards the drivers side). You need to use a universal swivel and about 12" of extensions to get the bolt out. Don't even think of trying to put the socket on by site. Simply grab the E8 socket and place it on the bolt by feel. It's helpful to put grease in the socket to stick the bolt into it when you remove it.
Now that the bolt is out, reach in that same area and remove the sensor.
Install the new sensor. I was able to take this picture with my phone so I could make sure the bolt hole was lined up. I suggest you do the same.
Then Install the bolt... How? by feel. I reached down and started the threads by hand. Then I put the E8 socket on a 3" extension, and snugged it up by hand. Then I tightened it using the 9: extension and a ratchet. Eaach time working by feel to get the socket onto the bolt.
Now plug in the sensor... once again by feel. Remember the latch will be oriented toward the center of the car.
Now you need to reinstall the wire harness bracket. Torque the bolt to 8Nm, Then install a new wire tie around the wire harness oriented in the hole and slot as before.
Reinstall the engine cover and check your watch. Most productive 30 minute repair ever.
Thanks for all the helpful info, I just completed the work with no hitches following exactly your procedure and I was done in 2 hours which included a run to Kragen for the sensor and a socket
Originally Posted by OldSchoolC240
Having just done the CPS replacement on my 2003 C240 wagon, I thought I’d share my experience for those of you who will be taking this on. In the spirit of giving back to the community that has saved me thousands of dollars and given me the confidence to dive into some pretty complex repairs, I've compiled some notes.
I used the search function here at MBWorld to find what I needed to take this job on. I did find some ambiguities though so, I’ve committed my notes to the attached PDF. I used pictures that I gleaned through searching and I did take the picture of the tools with my phone.
Through the proper and exhaustive use of the search tool here, you’ll find most of the pictures you'll need. I would suggest searching on “MAF removal”, “Crankshaft Position Sensor” and “Air Filter removal” for photos.
All directions are for my M112.916 engine, from my memory and are provided for your entertainment and not as an official repair instruction. All pictures are the property of their owners and used here for illustrative/educational purposes.
Total pain in the a** but saved a lot of money by doing it myself. Took me about 3 hours. Bought the CPS from Oreillys/Kragens for $60 out the door. Second hardest part was locating the CPS even with all the pictures online. Once you remove the MASF, there is a wire harness under that and I thought that was the CPS. It's not. CPS is more to the right of the block and down lower. Definitely need a bright flash light and a small mirror to find the CPS. The hardest part was removing the torx screw. That part took the longest and required the most patience. I used 1/4" socket. You must find the correct wrench assembly and extension, because you need a proper/good angle to unscrew the torx screw. Once you get that off, it's all downhill from there. If you plan on DIY, then the main thing you will need is the right tools, a lot of patience, and a good amount of time. Make sure you have plenty of daylight and some bright flash lights. Also, the engine needs to be cool. Don't try to change the CPS after you drove your car. Then you will need a big sleeping bag to lay across the engine because that is where you will be laying for a couple hours and you want it to be comfortable. Do a lot of research in these forums and get a tool list and get directions with pictures of what you are doing. Print them out and have them with you. That's what I did. Tips: after you get the new CPS in and you are ready to put the torx screw back, tie fishing string to it in case it drops. Then you will not lose your screw. To make it stay in the wrench you are using, stick toilet paper in the wrench head and then put the screw in. It will stay in place and you will have fishing string tied to the screw just in case it falls out. An extra person with you also helps. I almost quit so many times. Was even looking on CL for mobile mechanics. I'm glad I stuck with it tho. Saved a ton of money. Hope this helps. Car is running great now with out stalling!
Hey, I'm midway through the job (where I've finally removed the old sensor) and pausing now to complete tomorrow morning. Your tip here on finding the CPS was GOLD for me. I took the mass airflow out as well, and was struggling to find the CPS and thanks to you I knew to look at the connector below the MAF and go lower and right. BINGO. Thanks a lot for that one!
By the way, I wish I'd read ahead to your tip on tying a bit of fishing line to the screw. Mine dropped and I have to go find it in the AM.
I don't see any lines that are not in their place. The sputtering comes back after driving the car for a while, when the engine is hot and only at close to idle speed. It is similar to how it was acting with a bad CPS but without any stored codes/CEL now. When I replaced the CPS on my BMW I had to have the dealer reset it before it started working fine. Everyone says you don't have to reset it on the Benz, but I do have the Carsoft - is there a way to reset it from there? I tried erasing the adaptation values with Carsoft, but that did not help.
What did your BMW dealer 'reset'?
If there is a diagnostic code set, you can erase/reset that code. However, if there is no diagnostic code, what are you going to reset?
2017 GLA 250, 2011 C63 P31 (p30 w/ lsd) (in repair), 2005 C230 Sport Eurocharged, 2003 C320~sold
Originally Posted by pcy
What did your BMW dealer 'reset'?
If there is a diagnostic code set, you can erase/reset that code. However, if there is no diagnostic code, what are you going to reset?
pcy When I replaced my CKP I didn't have to reset anything and it worked fine but later I did find somewhere in STAR to reset it. According to WIS it says to "Carry out first initialization and then sensor rotor adaptation using STAR DIAGNOSIS" It says this is in Engine Control Module --> Adaptations --> Learning Processes
2003 Mercedes C240, just replaced the Maf air flow, the engine starts sometimes after sitting for a 30 to 40 minutes, though only runs for 20 minutes. I checked for fuel at teh rail and there was good flow and pressure. However there was not getting any spark. Going through teh fuse box revealed no help as all fuzes were fine. I am interested in checking the Crank Shaft position Sensor and teh wireing to and from as it works sometimes.
2017 GLA 250, 2011 C63 P31 (p30 w/ lsd) (in repair), 2005 C230 Sport Eurocharged, 2003 C320~sold
Originally Posted by krinderhagen
2003 Mercedes C240, just replaced the Maf air flow, the engine starts sometimes after sitting for a 30 to 40 minutes, though only runs for 20 minutes. I checked for fuel at teh rail and there was good flow and pressure. However there was not getting any spark. Going through teh fuse box revealed no help as all fuzes were fine. I am interested in checking the Crank Shaft position Sensor and teh wireing to and from as it works sometimes.
There's no checking it....usually there isn't a code and is common for them to go bad. They are also cheap enough to replace as a maintenance item and less than a MAF.
RE: Ignition Spark Fail stall no start works sometimes
Originally Posted by krazzdav
There's no checking it....usually there isn't a code and is common for them to go bad. They are also cheap enough to replace as a maintenance item and less than a MAF.
Thank you Krazzdav
Yes, I just referenced the CPS for $71.00 at NAPA, Though the strangest thing just happened.
I was leaving the Walmart after the customer turned the car over to me and he walked home, because it stalled while leaving the first time.
1. I let set 30 minutes and it drove to the intersection were it stalled again
2. I pushed it to a parking spot and walked home. Came back an hour later and drove it to my house 3 miles.
3. I turned it off put OBD tester on it and turned key on No codes.
4. I removed the engine covers, and fuse box covers and checked it again. it gave a P0335 code and would not start.
5. The Battery acts dead wont do anything
I am sure it is a bad wire connection somewhere. i will clean teh battery cables and keep a close eye on teh wiring
Also the pressure sensor on the fire wall keeps clicking
Last edited by krinderhagen; 12-28-2014 at 01:04 AM.
Reason: spelling
2017 GLA 250, 2011 C63 P31 (p30 w/ lsd) (in repair), 2005 C230 Sport Eurocharged, 2003 C320~sold
That price at Napa is high but if u need it right away u don't have a choice.
Well since u do have a code then it def is bad but you should still be able to turn your car over/crank but just wont start.
How you describe it starting after sitting is classic symptom of a bad CKP but not how your describing the battery acts dead. While checking things you might have unplugged something or blew a fuse.
RE: Ignition Spark Fail stall no start works sometimes
Thank You Krazzdav
While i was writing this post the engine stalled again
Originally Posted by krinderhagen
Thank You Krazzdav
Yes, I just referenced the CPS for $71.00 at NAPA, Though the strangest thing just happened.
I was leaving the Walmart after the customer turned the car over to me and he walked home, because it stalled while leaving the first time.
1. I let set 30 minutes and it drove to the intersection were it stalled again
2. I pushed it to a parking spot and walked home. Came back an hour later and drove it to my house 3 miles.
3. I turned it off put OBD tester on it and turned key on No codes.
4. I removed the engine covers, and fuse box covers and checked it again. it gave a P0335 code and would not start.
5. The Battery acts dead wont do anything
I am sure it is a bad wire connection somewhere. i will clean teh battery cables and keep a close eye on teh wiring
Also the pressure sensor on the fire wall keeps clicking
UPDATE
After the battery appeared dead and i had a P0335 code, i came inside and wrote the previous post.
I then went back outside and checked OBD II codes again. It said No codes and started right up. No problem. I then went under the hood and wiggled the wires battery terminals and plugs to everything. The was no change whats so ever. I pushed and pulled and no change. the wires look new no problems.
Thought:
While i am checking for shorts and bad connections. Does the alarm act this way as such that no spark cranks a few times then battery acts dead. then after it sits everything works fine
I will test battery too
Last edited by krinderhagen; 12-28-2014 at 01:03 AM.
I had thought the ignition timing for the spark of each of the dual cylinder plugs, was not part of the closed loop calculation.
I am thinking that when the 02 Sensors heat up and it goes from open loop to close loop is when it reads the Crank Position Sensor. in which case a malfunction of it causes it to of course shut down.
1. As dangerous as it is and how much i hate temperamental parts
2. Why would work for a certain amount of time
3. I was surprised to see the code clear its self after it cools downs or sits for a while
4. though if it should a part failure when going into closed loop why wouldn't it return to open loop and keep running.
Also with the code present when it's failed is a good indication that is the fault so go ahead replace it and see what happens
That make's sense ! Autozone offers offers
1. Duralast/Crankshaft Position Sensor Price: $96.99
Part Number: SU13243 Warranty: Limited Lifetime
2. Bosch/Crankshaft Position Sensor Price: $48.99 No warranty
With any luck it will be the Bosch that fits
I will put when it gets hot it quits working, and i back that up with the fact after running for period of time it quits !!
Thank You Right-On!!
At the Autozone
Duralast/Crankshaft Position Sensor
Price: $96.99
• Part Number: SU13243
• Warranty: Limited Lifetime
Bosch/Crankshaft Position Sensor
Price: $48.99
• Part Number: 0261210170
Last edited by krinderhagen; 12-28-2014 at 01:07 AM.
2017 GLA 250, 2011 C63 P31 (p30 w/ lsd) (in repair), 2005 C230 Sport Eurocharged, 2003 C320~sold
Originally Posted by krinderhagen
That make's sense ! Autozone offers offers
1. Duralast/Crankshaft Position Sensor Price: $96.99
Part Number: SU13243 Warranty: Limited Lifetime
2. Bosch/Crankshaft Position Sensor Price: $48.99 No warranty
I will put when it gets it it quits working, and i back that up with the fact after running for period of tie it quits !!
Thank You Right-On!!
I forget where I got mine from but go with the Bosch one as that is OEM. The new OEM part# is A0031532828 for the M112
You can save about $10 if you want to wait and order it online -- a quick search has them from $33-$38 @ rockauto, autohausaz and amazon -- there are many more places you can get them from too
I forget where I got mine from but go with the Bosch one as that is OEM. The new OEM part# is A0031532828 for the M112
You can save about $10 if you want to wait and order it online -- a quick search has them from $33-$38 @ rockauto, autohausaz and amazon -- there are many more places you can get them from too
yea i will talk to the customer see if he will wait he has another car he is using now
06-10-2015, 01:23 PM
I had thought the ignition timing for the spark of each of the dual cylinder plugs, was not part of the closed loop calculation. 
