Was it the VW MAFs or wasn't it? - The Unofficial BMW M5 Messageboard (m5board.com)

gtobynj · 4th July 2006, 05:58

And should I put them back on?

The usual MAF type problems, hesitation, rough running when cold, yada yada, etc.

Bought some Radio Shack electronics cleaner and cleaned my MAFs. Night and day difference, or at least night and dawn - much better, but not quite 100%, so ordered the VW MAFs.

Installed 'em and got my 100%. 250 miles later, SES light and I am on reduced power (not limp home, but boomy and a bit under the weather). So I swap the BMW MAFs back in and after 200 miles or so, the SES light goes off.

In the meantime, I had booked her an appointment with the quack. They pull the codes and get something they told me they (said) hadn't seen before "caused by 0000005/4 1214710/4" which relates to a pre-CAT O2 sensor.

BMW SIB 12-07-04 related to this particular error code and required re-programming of the DME, which was carried out.

SO:
Was the error caused by installation of the VW MAF?
Was the error triggered by the VW MAFs "NEW" status, but not going to be an ongoing issue?

Do I put the VW MAFs back on - they seemed (butt dyno) to smooth out the engine a provide more linear power.

Opinions please?

gsfent · 4th July 2006, 06:05

Quote:

Originally Posted by gtobynj

And should I put them back on?

The usual MAF type problems, hesitation, rough running when cold, yada yada, etc.

Bought some Radio Shack electronics cleaner and cleaned my MAFs. Night and day difference, or at least night and dawn - much better, but not quite 100%, so ordered the VW MAFs.

Installed 'em and got my 100%. 250 miles later, SES light and I am on reduced power (not limp home, but boomy and a bit under the weather). So I swap the BMW MAFs back in and after 200 miles or so, the SES light goes off.

In the meantime, I had booked her an appointment with the quack. They pull the codes and get something they told me they (said) hadn't seen before "caused by 0000005/4 1214710/4" which relates to a pre-CAT O2 sensor.

BMW SIB 12-07-04 related to this particular error code and required re-programming of the DME, which was carried out.

SO:
Was the error caused by installation of the VW MAF?
Was the error triggered by the VW MAFs "NEW" status, but not going to be an ongoing issue?

Do I put the VW MAFs back on - they seemed (butt dyno) to smooth out the engine a provide more linear power.

Opinions please?

Unlikely it was the VW MAF's. Lots of folks here have used them with good results. I would guess you have a CPS starting to go bad. That will give a bunch of different false codes, including a bad O2 sensor, and sometimes a bad VANOS. I would reinstall the VW MAF's. It may take the car a couple hundred miles to adapt to the new MAF's.
Regards,
Jerry

Mattkins99 · 4th July 2006, 12:12

Well, if your O2 sensors were bad, it would make sense that the bad MAFs would mask the problem.