denraweb@yahoo.

2003 m271 6 speed manual

Do I or do I not need to relearn a new crank sensor with star after install? I've heard both being true where only one can be. Anyone know for sure? I bought a new Bosch crank sensor, but haven't put it in because I don't have access to star. TIA

RWDlifer

No. Remove old one, plug in new one. Done.
BTW the crank sensor on the M271 is a beeyatch to get to, hope you have knuckle insurance lol...

RedGray

Yes and no.
See the attached document from WIS.

According to MB, a re-calibration is required whenever the crankshaft position sensor is replaced.

Fact, that is very common for many/most manufactures.
Fact, many people replace the sensor, and never do a recalibrate.

If someone is going to do quarter-mile or dyno runs, then only a fool would not do a recalibration.

For "most" ORIGINAL EQUIPMENT sensors, for most drivers, the engine will be "fine" without a recalibration.
The firing of the spark may be a little too early or a little too late. That's similar to advancing or retarding the distributor in older cars.
So...
The engine may have a little less or a little more HP.
The engine may have a little less or a little more MPG.
The engine may pollute a little more or a little less.

Imho, unless the engine had a boarder line problem (such as being on the verge of detecting a misfire), not doing a recalibration shouldn't make much difference.

If you want, you can have an independent mechanic (or a dealership) do the recalibration procedure.

For people in America, from ebay, they can buy a china-clone STAR system for ~$700.


Good Luck.

denraweb@yahoo.

Thanks for the info! Tackling it today.