Need Help!!! DSC, Brake lights, Stalling, limp mode, you name it.

[Brianben95]

Hello, this is my first time ever using a forum, I'm desperate, so I hope i posted this in the right spot please bare with me. I'll be as detailed as i possibly can. I've seen similar symptoms to the ones I'm having and I've read countless forums but they usually have different symptoms and solutions, if anyone has seen this before and can direct me to the right place I will forever be grateful.

Ive had this car for about 2 years now, BMW 2005 325i 5 speed and when I got it, it didnt have AC. So eventually some shit with my AC messed up and my car overheated pretty badly and the AC unit in the hood caught fire, I dont know dick about cars so bare with me with my explanations. I ended up getting the whole AC unit replaced. After that my car I started to get RPM surges whenever i pressed down on the brakes, like if i was hitting the accelerator, regardless if i was in gear or neutral. drove like this for a few months after a mechanic told me it was the brake pump and not to worry about it. But i recently started to go to a new university thats 25 miles away from my home, 5 days a week.. so i started to put alot more miles on the highway and I started to get weird symptoms, when on the highway at 60mph on 5th gear it would sometimes jerk and the rpms would spike down and back up and then my EML DSC and brake light would come on and she would go into limp dick mode, giving me a hard time accelerating. So i went to another mechanic and they told me it wasnt the brake pump that it was a sensor, so i changed the sensor, i dont know which off the top of my head but i can find out. The next day after changing the sensor i got in and it felt amazing, i would put my foot on the brake and the RPM wouldn't rise. So i went to school, in the morning and everything was fine. When i got out of class right before i could even exit the university i came to a stop and the car stalled, I tried getting her back on and nothing, the engine would start to turn with little success and i had the same lights DSC EML and brake. I had her towed home and waited for the mechanic to come see it, I didnt touch the car. when the mechanic got there he tried turning it on and it turned on like nothing. nothing on the dash either. we ran the computer and got a crankshaft sensor code, which i can find out exactly which. he spent about an hour turning it on revving the engine driving around the block and nothing. so i didnt touch it the next day cause it was the weekend and i had nowhere to go, but then Monday came around and it was time to go to school. got to class fine. omw back home on the highway on 5th gear 60mph, it stalled. I put it in neutral and back to fifth and it came back to life, the engine didnt turn back up or anything lights just came back on and it kept driving. But the DSC light and brake light came on and i could feel a loss of power, felt hesitant to accelerate. got home, turned her off and immediately back on cause this seems to clear the codes but she had a hard time turning on. so i turned it off and left it for a few hours, after a while i tried taking her out again around the blocks and nothing.. next day same thing, omw to school, its fine. omw back on the highway same thing. I also noticed that if im on any gear and go straight to neutral instead of down shifting the RPMs get right under 1 and the car starts to rattle ever so slightly like its going to stall then stabilizes, and this is constant, i can repeat it 100 times. The car has gas, oil change is up to date, any maintenance is up to date as far as i can think of.

I live in south Fl, and usually in the mornings the car runs fine i get to school no issues, after class which is usually 2 hours or so, i get on to the highway immediately cause the uni is right next to the highway and not even 5 minutes into it my symptoms manifest. sorry for the long post, i tried to be as detailed as i could, i want to fix this im too invested into her lol and i need a car to get to school everyday. thanks in advance.

[Brianben95]

Update, so i ran a computer and I got the code P0335 could the crankshaft sensor be responsible for all my symptoms?

[Brianben95]

If anyone is having a similar issue, I ordered the crankshaft position sensor to change, and while i was working my way in to put it in i noticed my air intake hose was torn to shreds... I held off on the sensor, with hopes that changing the hose would fix my problem and thus far... no stalls. moral of the story, look for torn hoses.

[dworthy]

Welcome to the Forum!

Yes you did post this in the correct place, seems I missed it.

So whom ever you took it to in the first place, I would not go back to them. Ever.

For me, it sounds like the Crank Position Sensor, as you do have a code for it. Now what brand did you buy? If it was the cheapest "Made in China" you could get, well I would return it ASAP. Only 3 brands are worth the bother when it comes to sensors on a BMW: Hella; Bosch; and Siemens.

Lastly you need to get all the codes from every ECU in the car, from the DME to the ABS. If any light is coming on, a code will be stored, and sometimes the same code will be stored in multiple ECU's. You have to check and clear them all. It would help if you can post up the exact code and wording.

[Brianben95]

Thanks for the reply. So as I was changing the crankshaft i noticed my air intake hose was torn up, i replaced that first instead of the crankshaft to see if my problem was really just a vacuum leak and so far, fingers crossed, its been two days and I haven't had any issues. I would get the codes but the mechanic who had the computer tried charging me 300 dollars to replace the crankshaft so i told him to fuck off.

[dworthy]

I hope that 300 bucks included the sensor too.

But yes, these cars are very sensitive to vacuum leaks and at times all kinds of funky things happen.

[Honolulu]

Find someone with a generic scanner and clear all the codes. Drive around the block and see if any codes come back, or which ones re-appear. That will instruct what you do next.

Sometimes one fault can trigger multiple codes, making you thing the sky is falling, when it's only one fault and the others are "just along for the ride". So it's important to start clean, and check frequently, and look to the first code that comes up. This isn't foolproof, but a logical sequence to pursue. Some shops will read/clear codes for free. Call around, and don't drive with an unsafe car. Your life, and/or someone else's, may depend on it.