Bill109

Hello,
I've come here in desperate need of help.
My 05 m54 has been in shops the last three months and nobody has been able to properly diagnose this car. Even the dealer is going on three weeks. I've spent almost 2k at the dealer trying to fix it and we'll over 1k at other shops.

The car keeps going into limp mode.
Here's what happens. (Manual transmission)

If I Drop the rpm's then, stomp on the gas.. It goes into limp. The rpm's rev rapidly between 0-1k and the car gets increased emission, stability control, and engine malfunction, and sometimes cruise control faults. Then it loses all power and MUST come to a stop so I can turn the key on and off. The car then "resets" and will drive off until the next fit.
Sometimes the codes will disappear, others it won't.


So far;
New pcv (oil separator)
Oil level sensor and new retrofit wiring harness. New MAF and dme update, new intake boot, new manifold gasket.
Air box filter
Vanos has been considered as well... However I'm waiting for BMW to double check it.
Any insight here? BMW wants another 900 to keep going on the next guess.. I mean diagnosis.
I need any help you could give me!

gjeoc

Sounds like an electrical issue, use a voltmeter and see what voltage the alternator is putting out, also measure the voltage of the battery as well.

E60Japanese

I had a similar issue and it was electrical.
Noone knew what mine was. The RPM would sway between1,500 and 1,800 while holding the pedal still.
I could also flatten the car and it would hiss and go flat and sometimes stop

in the end it was a frauctured wire connecting to my 3rd cylinder coil due to heat
when the car was idling the wire made a good enough connection but under load it failed

I found the wire by accident and all my problems went away

E60Japanese

did you get any fault codes?

seanjordan20

Do not let he stealership rape you. You brought it in for a specific reason they guessed at it and did not fix the problem. In that case they replaced the part for free or will put my old part back on. I had the same issue with a dealership with my starter they replaced everything but what I told them to. In the end it was the starter and they reimbursed me for everything and replaced the starter under a good faith warranty. It only cost me $150 out of my pocket. As long as you let them take your money they will. Be firm and tell them the problem you initially brought it in for is not fixed and you are not paying them a dime until it is. Throwing parts at a problem is what BMW is good for. Do not let them do it at your expense.

You are paying for a service and if it is not done correctly they do not get paid!!!

Andrew06

+1 on all of these points, they are using the "diagnostic" skills of a high school with his parents credit card. Lets replace this, no? Just replace this. Get your car and hopefully money back asap and find an indy shop that will focus on fixing your issue, not just running up your tab at the parts counter.

Bill109

After everything, my Indy thinks it's a clogged catalytic converter.
They think there's to much back pressure because it Can't flow freely causing unmetered air to go back into the crank case.

Going to Try fixing it one more time and then it's trade in time. I've had my eye on a nice 09 red on red e92. I'll keep Eveyone posted on if this is the issue or not. Really Hope this fixes it.. I think

BostonJon

have you looked under the car when this happens? i've had a clogged cat on another car and it was literally red hot when I got home and looked under the car.

rice_rocket88

+1 on the bright glowing red on a clogged cat.. it started to make my carpet... squishy.. that was nuts!

BostonJon

you know, if it does turn out to be the cat and the dealer missed that all along and just continued to throw parts at the problem, i think you've got a pretty good case to make to BMW NA and ask for a refund.

as someone else mentioned, this is one of the reasons that I always ask for the old parts to be left in my car when the work is finished. obviously, i want to ensure that the parts were actually replaced and verify that the part was from my car. but also for the reason that your situation has highlighted. if they replace a bunch of parts and the problem is not solved, its a lot easier to go back and tell them that you arent paying for the new parts and they can put the old parts back on if you actually still have the old parts.