In Reply to: Re: conclusion (m) posted by Neil Deshpande on October 25, 2001 at 20:55:53:
I didn't know the spark plug wires unscrewed, the ends look to be molded on. My repair was completed with the sensor on the cable.
My pickup was broken where the cable enters the donut shaped (encapsulated ferrite) part. I carefully carved all of the plastic away on the cable side until the wires were exposed (yellow and black). Then I carved plastic away from the ferrite until the fine wires were exposed, being careful not to scratch or cut them. Then I re-soldered the yellow and black wires to the enamelled wires. In order to solder to the enamelled wires, their coating needs to be scraped off using fine sandpaper or an exacto knife.
After the solder process, I checked the circuit with a DMM, dressed the repair to approximate the shape of the original sensor, then placed some epoxy over the repair for strength.
If the fine wires are too short to re-attach, I suppose you could re-wind the core with some new wire. A bit more carving on the housing would be required. Just make sure to use the same number of turns around the ferrite.
This repair was a "what the hell, let's see if it fixes the problem before throwing more money at it" solution which turned out better than expected. My main motivation was to avoid replacing a good set of plug wires just to fix the sensor that now I discover isn't included anyway!
Please let me know how you repaired the inductive pickup. Mine is broken. Did you remove the enamel on the wire and then some on the coil and just solder them together? I agree that a few ohm will not matter on this. When I said that I meant the crank sensor and that too I was tentative about. The inductive pickup that you repaired should be quite resistance insensitive.
Also, you can actually buy a new pickup and slide it onto the old #6 wire by unscrewing the plug end of the wire. I'm not 100% sure how it comes off, but I know it does so non-destructively. A new plug set will not have the pickup installed. Seeing that the pickup is $100 and the wire set is $280 or so this is not surprising.
I am surprised to hear the engine does not have sequential injection. I have no information on the injection pattern you describe, but it seems reasonable.
I am glad your problems went away, particularly the catalyst 'blowing out' so quickly.
The inductive pick-up on #6 plug wire was the part I repaired. Immediately after the repair, the car was much better but not 100%. Since a few days of driving have elapsed, the car is back to its old self and runs perfectly. The sulfur smell has disappeared.
As for the repair changing the impedance spec of the pickup, I'd be suprised if I lost more than a couple of millimeters of the original assembled length of the harness and certainly didn't lose a turn around the ferrite core. I suspect if you made the repair without changing the number of turns around the core there would be no difference in the sensor's function.
The M5 doesn't actually have sequential injection, it is a bank firing type. There are 2 electrical circuits only and they fire odd and even cylinder's injectors alternately. Repairing the sensor did make a definite difference to my engine's smoothness and I would recommend the repair to anybody with a desire to repair without spending $$$ on new plug wires.