Hello everybody,

when i bought my car it has 0746 (P0172) and 0750 (P0175) error codes. I checked for leaks and found MAF elbow is cracked i renew it, but problem still persist. I clean maf sensor. didn't notice anything.
At this time;
- The engine is noisy.
- Acceleration is very bad.
- Cutoffs when accelerating.
- Sudden deceleration when you take your foot off the gas.
- Vibration at idle.
- Fuel consumption is normal not very bad.

And adaptation data is -6.00 % (minus six)

Then i Buy new MAF sensor Chinese cheap one it is better;
- Engine noise is better more quiet.
- Accerelation is good.
- No Cuttoffs when accerelating.
- Vibration at idle (no misfires)

but now still has fault codes but this time;

0745 (P0171) and 0749 (P0174)
and Self adaptation Range is +6.00% (Plus six)

Xentry says;
-inspect intake system leaks
-inspect exhaust leaks.

Where should I focus? How can I do a test? thank you.

Car 2007 ML350 4matic 164.186

 

You never mentioned that you deleted all codes. Have you? Read #11 in PDF.

 

Yes, i delete all codes.

I have also Xentry Software, from learning process, i do "resetting of adaptation data" and "resetting the cold-start adaptation values" process.

And today everything is normal when i drove, i go for a shopping parked then i turn back, i start the car and it shakes too much. i connect diagnosis read data, cylinder 1 and cylinder 4 is misfireing too much. i check maf and re-assemble nothing made any difference and i drove car after few minutes it get normal no shakeing no misfires.

 

I would think there is an unmetered air problem. I suggest that you remove the MAF Sensor and see if any of the seals are damaged.