1998 BMW 540i emissions failure

HA1381

MEMBER
1998 BMW 540I
V8
2WD
AUTOMATIC
97,685 MILES

Ive done a major tune up on my bmw changed all sparkplugs, ignition coils, oxygen sensors, mass air flow meter, radiator and oil after this I drove the car roughly 600 plus miles as required by manufacture afte this I drove to get an emissions test and it failed
my? Is why did it fail doing all that I did.

3 Replies

DOCHAGERTY

MECHANIC
9,601 POSTS

What failed, tell me the numbers.

Was this

answer

helpful?

Yes

No

Saturday, May 9th, 2009 AT 5:23 PM

CHARLESTHIELE

MEMBER
7 POSTS

There were lots of problems with catalytic converter failures on these early 540i's, my 97 had both replaced while under warranty and I wound up buying another set recently as one of them started rattling. I made things worse for myself by cutting off both stock ones and trying aftermarkets (Magnaflow are junk) which burned up in < 2000 km. I changed mine before I even started having emission problems or check engine codes because of the rattling. Stock ones are very $$ but a variety of shops agree they are the only option for reliable performance on the M62 V8 engines.