zhang@netscape.com wrote in
news:1107394002.114145.262850@f14g2000cwb.googlegr oups.com:

>
>> > No. It is a part of one of the rotational sensors in the
> base/housing.
>> > The rotor part of the topmost sensor has a color indicating of
> going
>> > through a very high temperature, and the stationary plastic part
> with a
>> > metal contact (I do not know the name) has small cracks. I don't
> know
>> > how these rotational sensor work. It would be wonderful if someone
> can
>> > explain it.
>>
>>
>>
>> Have a look at these drawings:
>> http://www.tegger.com/hondafaq/distrotor.html
>>
>> What number is it on the LOWER drawing?
>
> It is #4, the housing. Did you see there is a smaller rotor fixed on
> the shaft, and to its left there is a bigger bent plastic piece. They
> are one of the CYL/TDC/CRANK sensors in the distributor. Do you know
> how they work? Can a misreading from these sensors cause no sparks?
>
>


Maybe.

There are three of those sensors:
1) Cylinder (detects #1 cyl)
2) TDC (used at startup)
3) Crank angle (rpm sensor & timing)


All these are just Hall-effect sensors. They use the small voltage created
by the proximity of a magnet to signal to the ECU.

Normally, failure of one of these three would set a 4, 8 or 9 code.


A few questions here:
1) What started all this anyway? (pun not intended)
2) What symptoms did you experience prior to complete failure?
3) Were there any ECU trouble codes?
4) Did the engine misfire, or the tach act oddly?
5) Had you replaced the timing belt just prior?

--
TeGGeR®

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/