replaced cam sensor, still code P0340

[Buzzfish]

It threw the same code the second time i started it after I replaced the cam sensor and cleared out the codes. Any ideas of what else could be throwing this code? I'm also getting the P1519 VANOS malfunction code, which i had assumed was because of the bad cam sensor.

Another thing, when i did the job I didn't detach the battery cable, but I did do it after i finished up to "clear the computer" and it was only for a short amount of time, possibly not long enough. For these cars, is there a certain amount of time that you need to disconnect the battery in order for the computer management junk to reset?

thanks in advance..

[Buzzfish]

I'm already off on page 2! I'm going to give this a bump since I'm somewhat desperate to get this fixed.

[GrifM3]

Buzzfish

I'm not too sure why you chose to replace the cam timing sensor when you read a VANOS failure code. 2 seperate things. VANOS has been known to fail on these cars, even at low mileage. Any good dealer or independent should be able to check the VANOS function very quickly. Then you'll know for sure.

Also, I don't know that disconnecting the battery will do much for you. I noticed in your description you have a 97, which makes it an OBDII car. OBDII won't reset the light without going through a few "drive cycles." Basically, it's looking, over a period of time, for the signal from the failed component. If it doesn't see it again after few drive cycles, then it will turn the light off. If you want more info on how OBDII goes about its business, do a search here and elsewhere. Even after it turns off the light, the code(s) will still be in the ECU. You will have to use your reset tool again to clear those.

HTH,

GrifM3
Dinan S2

[Buzzfish]

Thanks for the response.

I replaced the cam sensor because I was getting two codes: one was P0340 which is a "Cam Position Sensor Circuit malfunction" and the other was the VANOS failure code, i think P1519? I can't remember exactly. But, my thinking was that the cam sensor was failing, and that was causing the VANOS to give up, thus throwing the other code.

I'm still trying to figure out the OBD2/ECU interaction in the car. I still get the obd code immediately after startup and after clearing it with my tool, so I gave up trying to clear that out BUT last night I disconnected the battery cable for an hour and the difference int the way the car ran was noticable. I believe i reset the main ECU? Now it feels fixed by the way it runs, but the OBD code is still there.

Are you saying the OBD code will clear out after a while if no no codes are thrown out to it? Will the codes in the ECU ever clear out without a proper scan tool?

I'll do some searching around, as you said. I hadn't found anything before but maybe I'ms earching for the wrong thing.

thanks again

[GrifM3]

The codes will not clear on their own, only by tool. However, as previously stated, the light may go out. If the problem has been fixed, the light will go out after a few drive cycles. But, not if you have multiple codes that haven't all been addressed. The only thing you will accomplish by disconnecting the battery is resetting OBDII adaption.

Go get your VANOS checked out. It's a very basic system. It shouldn't cost a lot of money for diagnosis. Replacing it on the other hand is a different issue.

HTH,

GrifM3
Dinan S2

[Buzzfish]

Allright I'll just let the freaking OBD alone for now then, what a pain.

Thanks for your help, since i just bought the car 3 weeks ago I set up an appt with a BMW guy next week to give it a once over and tell me what he thinks.

[Buzzfish]

Update - VANOS was toast, the little piston in there was sticking. I had it replaced and all is well.

lesson be learned - when the vanos goes, have someone look at it because it throws every code in the book it seems like.

thanks for all the help.