HELP !! BMW E60 2007 codes: P0700 P0335 P1727

[bmw525i2007]

Hi everyone,
So i have a BMW 525i 2007 (E60) 150000miles

The codes I get from the OBDII are
P1727
P0335 Crankshaft positioning sensor (A circuit)
P0700 Transmission Control System (MIL request)

Every 20-30 miles or so the transmission goes into a failsafe mode and I have to stop and restart the car several times till it goes away. When on Failsafe mode, I try to restart it, the car takes around 5-10 sec before it starts and when it does that it still goes on failsafe. When restarting 3-4 times it evantually starts fast (1-3 sec) and is not in a failsafe mode.

Everytime the problem acts differently.
Sometimes it will go to failsafe when i am driving on the highway, sometimes when i start it in the morning. It can go without failsafe for a day or two and then sometimes it will bring up the failsafe 10 times in one day. so very inconsistent.

In General I don't experience any harsh shifting or any transmission issue.

When not on failsafe mode It will rev sometimes inconsistently. The RPM just goes up while on the same gear, once or twice while driving,
The car will die sometimes when comes to a complete stop.

The mechanic told me to change the entire transmission. I don't wanna believe that it's the tranny.

Any suggestions ?

The coils and spark plugs are all new. The battery is only a year old and it works really well.

Is there any chance it can be one of the modules ? becuase it's so inconsistent and the car drives totally fine sometimes for up to 30 miles, i dont wanna believe its a hardware issue.

[bmwdirtracer]

I have just finished a protracted issue with the same problem, on the same year and model car.

Step one is to replace the crankshaft sensor with a brand new OEM part (VDO Siemens). You'll also want a new o-ring. When you install the new sensor (which can be done from underneath, by braille), use a mirror on a stick to make sure that the sensor is sitting squarely in the hole, and that you can't see the o-ring.

Then clear the codes, and drive the car. If the problem recurs, you're going to need to test the wires between sensor and the computer.

Don't bother with the transmission issue until after the crankshaft code goes away, because when the engine speed signal goes away, the transmission goes into limp mode.

The p1727 MAY indicate a serious problem (Coast clutch inductive signature?), but handle the crank sensor code first.

[bmw525i2007]

Followed your suggestion !! CAR FIXED AND RUNS GREAT !! Thanks a lot man. Only changed the crankshaft positioning sensor. they charged me a lot for labor but i didnt care just wanted to get it done. it was $400 all together, 160 for a part plus 250 for labor. Anyways. if anyone has this problem make sure to do this first, and if you have a friend who can get to that sensor and change it you might get the job done for a lot less. I feel awesome now tho. all the lights were on and now every code just disappeared. even the break lights were coming on. lol for noooo reason. All just because of a stupid tiny sensor.

[328 Power 04]

That stupid tiny sensor is one of the most important sensors for the engine computer, so yes, it will affect so many systems.