titanmike

144K miles, just swapped the crankshaft position sensor yesterday, no codes, no check engine light still not fixed. Car starts fine but hesiatates or sputters upon take off not every time either just times like when traffic is stopped on the interstate. When up to speed vehicle runs fine I guess I am looking at maybe a fuel filter next????? Any help would be appreciated.

Thanks,

TM

DBAAlek

Did you get this resolved? I'm having the same problem and without an engine light no one can say for sure what the deal is. Any help is appreciated.

Thank you.

Neanicu888

MAF most likely.
Take out-clean-CRC MAF cleaner or similar.

art_arev

Just replace your MAF . Dont try to clean etc.... buy a new "Bosch" Maf sensor.
The fuel filter change is due every 60000km. If you can change it as well.

Neanicu888

Why replace if it's not throwing any codes? An OEM MAF can get expensive,probably around 300$. Sometimes cleaning them is enough...

art_arev

It might or it might not throw codes...You can get a bosch for around $150. The question is how long is cleaning going to last? Its just like the CPS sensor when it starts acting up its matter of time when you will be stuck in the middle of the road. Best is to change it.
PS. There is a resistor soldered inside the MAF sensor. Very often ( I've fixed 2 of them) you get a dry joint. Try resoldering the resistor connections. If you are lucky it might be as simple as that

Maj. Dundee

Art, the MAF Sensor is the most maligned component on the ML. Whenever there is a performance problem, the first thing that everyone mentions is the MAF Sensor, including M/B techs.

So many techs. have replaced MAF's with negative results, that M/B generated a 27 page document to stop the practice.

Secondly, the cleaning of the MAF Sensor hot wire is only to remove soot and deposits, which in fact works. It is not meant to miraculously repair an electronics problem within the MAF.

And lastly, the MAF circuitry is encapsulated within the plastic housing and repair or re-soldering is impossible. The only thing visible is the Intake Air Temp. Sensor (green arrow). The MAF Sensor wire can be seen through the small opening (red arrow).

Maj. Dundee

Problems like this are usually attributed to a small vacuum leak, probably at the rear of the engine.

Inspect all vacuum hoses everywhere but concentrate on the rear.

art_arev

Thanks for the info Maj.
The picture of the MAF you have sent clearly shows the "resistor" I was talking about ( I didnt know that was the intake air temp sensor ). The dry joint happens at these points were the sensor is soldered.
As per your advice I will try in the future to clean the deposits. Thanks again