Hello,

So I've had this worsening problem for a while now, and it's getting to the point where it's hard to drive the car.

Started a year or so ago with a camshaft position sensor error, ok, replaced that. Got the same error, replaced the sensor again and then got a crank sensor error. Ok, replaced that. Got the error again, replaced again, always with NTK sensors.

Car was ok for a while, then late last year the engine started randomly shutting off/cutting out while driving. It almost always started right back up again. So, knowing I had a new sensor on the block, I started researching and asking around other r53 groups what might be going on. Someone in a Facebook group suggested replacing the crank sensor pigtail as they can get oil soaked and might affect the wiring after years of driving. Well, the only one I could find online without cutting one off of a parts car came from Ali Express (I know, I know). So I ordered it and the quality seemed good enough, so I installed it with solder crimp connectors. All was fine for about 3 months until it started acting up again, and I removed the crimp solder connectors and physically soldered the wires with heat shrink tubing.

Fast forward to now and it's started randomly cutting out for a couple seconds while driving, then comes right back to life. Most of the time, even though I get the EML and service engine soon light when it dies, once it comes back to life it doesn't keep any of the triggered DTCs, but the times it has it's always the crank sensor. Now it's gotten even worse to where sometimes the car won't even start, or I'll be driving it and it just constantly stutters before it stalls. Earlier this morning it stuttered and stalled, triggered DTC codes p0335, p0336 with my traction and tire light on, until the next time it stuttered, and then it's like it clears the codes stored and the whole thing starts all over again.

At this point I'm not sure what to do, maybe it's the cheap pigtail I installed, maybe there's something else going on, I took it to a shop once and of course it didn't act up for them so they had nothing to work with. Battery charging voltage seems to be fine, usually 13.7 to 14.1 volts. Replaced the coil pack a year or two ago with an OEM replacement.

Could I possibly be looking at something else? Other than the sensor? I checked the battery connections, they seem fine, it's just weird that no codes are being stored like the system is shorting out or something. Could I be looking at the DME?

I don't want to just throw money at it, but it's also my primary vehicle so it hurts a little bit to not be able to trust it, and I'm limited in my own ability to do troubleshooting due to lack of anything other than basic tools, etc.

Hoping someone can guide me in the right direction, thank you.

 

Have you got anywhere with this? been forum absent so no help here....

P0336 indicates you have signal, but inconsistently / not within spec
P0335 is straight up CPS circuit malfunction.

I would lean towards that pigtail causing both, as i personally run NTK CPS without an issue, i doubt NTK would send you 3-4 duds. The BeijingExpress pigtail likely has weak pins inside, or loose connections to the pins.

The throttle body is somewhat known for having issues like this with the OEM mini connector, mine acted up, swapped throttle bodys to no avail. Then found someone talking about the pigtail, took a little pick and closed the pins, added some dielectric grease and it hasn't returned in years. It may be scrapyard time for yourself, or if needed i could likely source one from my stash up here in canada.

 

A charging battery (when car is running) should be 14.2V minimum or a bit higher (14.6V max). R53s are notorious for having issues with weak batteries. Test your battery and alternator.

 

I totally forgot to update this post, it turns out it was just a faulty crank sensor. I had thought that ntk would be a trusted brand, but apparently not, I went with an oem factory BMW sensor and the problem immediately went away. Sad that I went through all this trial and error and trouble for a stupid sensor LOL

 

Thanks for the update. Interesting find, did you source these from the same place each time? Currently running the NTK EH0347 personally without issue. Purchased mine through rockauto.

Happy your motoring along again!

 

Same and same, went through two of them. Can't understand it honestly LOL.

 

Hah what a good time... good to know and keep in mind though!

 

Indeed.

Had I just taken the car to a shop in the first place for proper diagnosis, I could have saved myself a lot of time, money and headache.