1998 M44 O2 Sensor question

[Peter12345]

Should a Feb 1998 Z3 have one or two O2 sensors ? My son got me a new CAT (Eurospare), and it has two sensor holes. The old Cat only has a single sensor.

I did wonder if someone had hidden the rear sensor somewhere, but surely that would trigger a fault code ?

Pete

 

[jonco]

Should a Feb 1998 Z3 have one or two O2 sensors ? My son got me a new CAT (Eurospare), and it has two sensor holes. The old Cat only has a single sensor.

I did wonder if someone had hidden the rear sensor somewhere, but surely that would trigger a fault code ?

Pete

There is only one on M44 European version.

 

[Peter12345]

ok thanks. Gotta return the CAT anyway, because after tightening the manifold flange, the angle is wrong & makes the rear pipe sit against the chassis. Compared it more closely to the old cat, and the flange is a degree or three wrong.

 

[jonco]

ok thanks. Gotta return the CAT anyway, because after tightening the manifold flange, the angle is wrong & makes the rear pipe sit against the chassis. Compared it more closely to the old cat, and the flange is a degree or three wrong.

B***er! Is your cat back a single section. Mine is two piece so has adjustment to correct.

 

[Peter12345]

It's one piece pipe with 4-bolt flange to manifold, and then a clamp joint after the cat for the rear box.

Got replacement cat yesterday (single sensor version), but it has the same issue where the cat sits slightly high, so rear box fouls chassis. Tried the old cat, and that sits straight, but now two replacements have this issue with the angle. Now wondering if the manifold is bent, and prev owner put a bend in the cat pipe to compensate.

Gonna look for longer rear box rubbers which should lower that and stop the fouling.

 

[NZ00Z3]

Can you turn the Cat up-side-down? Might have to cut the exhaust and fit clamp joiners.

 

[Peter12345]

Pipe is all one piece, so would require cutting. Wondering if there's a custom exhaust place nearby, that could put a few degree bend in it to lower the rear joint.

Otherwise a clamp band like this, with plenty of sealing paste might work. worried it will develop a leak though.