check engine light - BMW Forum

leobmw · 10-16-2003, 04:14 PM

I have a 99 528i with 51,000 miles and the check engine light just came on.
I know it wasn't coused by the gas cap....Does anybody know how to do a diagnostic on the OBDII without using a scanner? example on the OBDI u could press the acelarator 5 times with the key on position 2 and that would make the check engine light start flashing, and then u could figure out the faulty codes.
Please let me know if u know how to do it with the OBDII !!!

Ski · 10-16-2003, 08:53 PM

You sure it's not your 02 sensor??

leobmw · 10-17-2003, 08:59 AM

well i took the car to auto zone and the faulty code#P0740 thats the "electrical circuit for the torque converter clutch"
I think i would feel the tranny acting funny if that was the problem, but i dunno. Well to tell u the truth i've never had a car with a automatic transmision before so i dont know how its supposed to shift. Is It supposed to be pretty smooth when it shift in betwen gears?
Coz i can feel it shift a little hard from 2nd to 3rd at low speeds!!
Any imput would be very appreciated...

CosmosBlack · 10-18-2003, 12:03 AM

You shouldn't feel anything much during auto gearshifts, that's one of the beauty of BMW automatic transmissions! I would say, if you're not paying attention, you wouldn't even feel the gears change.

rdef · 11-28-2003, 03:55 PM

Quote:

Originally posted by CosmosBlack@Oct 18 2003, 12:43 AM
You shouldn't feel anything much during auto gearshifts, that's one of the beauty of BMW automatic transmissions! I would say, if you're not paying attention, you wouldn't even feel the gears change.

I have a '98 528i, and it shifted hard between 2nd and 3rd. The tranny finally failed after about a year of that. I had the tranny replaced by BMW, and soon after being replaced, it too is shifting hard.

Ever hear of this? Could it be a throttle sensor or other electronic component?

No error codes are being returned by the car.

Thanks.