P0068 maf/May throttle position correlation C250
#1
P0068 maf/May throttle position correlation C250
The dreaded check engine light appeared on my dash yesterday. Scanned the code and found the problem to be p0068 (maf/map throttle position correlation). I’ve seen this problem with the C300 and c350 but not a whole lot for the c250. Car runs normal, nothing noticeable has changed. I’m no mechanic but I’ve taken out a couple sensors, cleaned them, and reinstalled them and that was unsuccessful. Not sure where to go next besides the dealer and I’m not looking forward to that
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phandes (12-14-2023)
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2014 c250 M271.8
After more than a week of looking for cracks in hoses and ducts, spending ~$80 on 3 new MAP sensors and removing the throttle body for cleaning (thanks to FlexxAlexander for the YouTube video) I finally found the cause to be an extremely worn seal ring (part# 0219976545) that had shifted out of it's groove. I'm referring to the pipe leaving the intercooler going to the throttle body. Just an FYI that you might have to remove some ducts and hoses if you're chasing this code.
#3
Hope that is what it is, as I have replaced MAP and Intake control sensor.
Not a big deal as I have 140,000 miles and it is running smoother now, but no throttle response until it revs up takes awhile!
Thanks
Not a big deal as I have 140,000 miles and it is running smoother now, but no throttle response until it revs up takes awhile!
Thanks
#4
After more than a week of looking for cracks in hoses and ducts, spending ~$80 on 3 new MAP sensors and removing the throttle body for cleaning (thanks to FlexxAlexander for the YouTube video) I finally found the cause to be an extremely worn seal ring (part# 0219976545) that had shifted out of it's groove. I'm referring to the pipe leaving the intercooler going to the throttle body. Just an FYI that you might have to remove some ducts and hoses if you're chasing this code.
#5
My Car C250 2012 M271 evo,
I have P0106 & P0068,
Car run perfect with no issue at all, NO ROUGH IDLE
The only issue some interment loos power when push halfway accelerate then car run good with no issue
Replaced two map sensors and other Map sensor locate on intake pipe including Temperature sensor, clean throttle body also test all MAP sensors by multimeter and all good
Run the car for over 300 miles but the two fault back after one day driving especially no vacuum leaks at all,
Short term shows Zero % and long term shows 26%
Any idea to solve this issue.
I have P0106 & P0068,
Car run perfect with no issue at all, NO ROUGH IDLE
The only issue some interment loos power when push halfway accelerate then car run good with no issue
Replaced two map sensors and other Map sensor locate on intake pipe including Temperature sensor, clean throttle body also test all MAP sensors by multimeter and all good
Run the car for over 300 miles but the two fault back after one day driving especially no vacuum leaks at all,
Short term shows Zero % and long term shows 26%
Any idea to solve this issue.
#6
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2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
LTFT at 26% is over the max limit of +/-25%. It indicates too much air for the amount of fuel, or a lean condition. Lean is NEVER good with turbo cars. So, do NOT push it hard until you fix this problem.
Here is a good video to review. You say there is no vacuum leak, but how did you determine that?
Here is a good video to review. You say there is no vacuum leak, but how did you determine that?
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antboii (07-02-2024)
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2013 w204 c250 coupe & 2001 Dodge Ram 2500 24v Cummins
My Car C250 2012 M271 evo,
I have P0106 & P0068,
Car run perfect with no issue at all, NO ROUGH IDLE
The only issue some interment loos power when push halfway accelerate then car run good with no issue
Replaced two map sensors and other Map sensor locate on intake pipe including Temperature sensor, clean throttle body also test all MAP sensors by multimeter and all good
Run the car for over 300 miles but the two fault back after one day driving especially no vacuum leaks at all,
Short term shows Zero % and long term shows 26%
Any idea to solve this issue.
I have P0106 & P0068,
Car run perfect with no issue at all, NO ROUGH IDLE
The only issue some interment loos power when push halfway accelerate then car run good with no issue
Replaced two map sensors and other Map sensor locate on intake pipe including Temperature sensor, clean throttle body also test all MAP sensors by multimeter and all good
Run the car for over 300 miles but the two fault back after one day driving especially no vacuum leaks at all,
Short term shows Zero % and long term shows 26%
Any idea to solve this issue.
You confirmed no vacuum leaks with a smoke test ? Sometimes there could be a hair line crack in one of the plastic intake piping/PCV system.
If you're getting excessive oil in your intake system clogging the sensors, throttle body, and intake piping, and intercooler, it could be choking out the engine and trying to over compensate for the lack of flow in the system. This would lead me to double check your PCV system.
How often do you change your oil?
Ant
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C250 W204 Chassis, M271 evo engine
Hey @PHILOMINA , were the MAF/MAP sensors covered in oil when you took them out to clean and test them?
You confirmed no vacuum leaks with a smoke test ? Sometimes there could be a hair line crack in one of the plastic intake piping/PCV system.
If you're getting excessive oil in your intake system clogging the sensors, throttle body, and intake piping, and intercooler, it could be choking out the engine and trying to over compensate for the lack of flow in the system. This would lead me to double check your PCV system.
How often do you change your oil?
Ant
You confirmed no vacuum leaks with a smoke test ? Sometimes there could be a hair line crack in one of the plastic intake piping/PCV system.
If you're getting excessive oil in your intake system clogging the sensors, throttle body, and intake piping, and intercooler, it could be choking out the engine and trying to over compensate for the lack of flow in the system. This would lead me to double check your PCV system.
How often do you change your oil?
Ant
thank you for your reply,
I just Changed the oil with filter,
Two months ago, Deassmble intake manifold and test all PVC hoses located at the bottom of intake Manifold by handle vacuum pump then put new PCV Valve,
yesterday testd purg valve hose going to intake manifold and good,
also checked PCV hose comes from valve cover going all the way down to PCV hoses tree,
I attempted several different methods but Code P0068 come after one day driving,
I don't know if bad Intake manifold control sensor or something else,
otherwise I Have LTFT 26% & STFT zero,
LTFT doesn't go less than 18% whatever RPM 900 or 5000,
I don't know this is bad fuel delivery cass very high LTFT or other reason ?