X won't idel after replacing valve stem seals - receiving misfire codes.

[Purplefade]

Originally Posted by oldskewel

Nice work. I have a different engine (M54), but was following on hoping for a good outcome. Glad you got there.

As far as I know, there are not many plugs on these cars that can be mistakenly interchanged like that. O2 sensors are another one, so I labeled those carefully when taking things apart for the engine work last summer.

But for all the ~dozen or so connections in and around the intake manifold, not only is the cable length and bend a good clue, but the connectors themselves are keyed, so for example you don't actually need to worry about mixing up two nearby 2P plugs.

The keys in the connector will prevent that. I know you know that, but for others following at home wondering how hard it should be to take everything apart and put it back together, there is some perhaps non-obvious protection built in against problems.

So it's probably an easy mistake to make, since keeping absolute track of connectors is not usually necessary. Nice PSA for everyone that this is something to watch out for - just like the O2 sensor connections.

Thanks oldskewel



Is strange that they keyed nearly everything except the vanos, cps and O2 sensors, hmm, wonder if it was because there are 4 of each and they thought they'd really screw with us good when we finally needed to service those items...

[oldskewel]

Originally Posted by Purplefade

...Is strange that they keyed nearly everything except the vanos, cps and O2 sensors, hmm, wonder if it was because there are 4 of each and they thought they'd really screw with us good when we finally needed to service those items...

Yes, I agree it is probably due to the parts themselves being identical / interchangeable. If they wanted to key things to distinguish left vs. right, they'd need to sell different parts for left and right sensors, and left and right cables, etc. And yes, they'd surely make us pay for the extra cost that comes with that at the cash register.