Nissan Repair: 89 Nissan 240sx intermittent miss, crank angle sensor, throttle position sensor

Question
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Followup To
Question -
The subject car now has 199875 miles and has developed the intermittent miss at around 3100 - 3500 rpm.  Occurs at times through up shift (feels like engine cuts out completely then back on) and also at highway speeds (might last fraction of a second or several seconds).  No backfiring.  Might not happen for days and then a lot.  Now also at times after highway drive doesn't want to idle (shuts off), but only rarely (twice in the last week however).  Have replaced plugs, wires, coil, cap rotor, throttle position sensor, fuel filter.  Injectors replaced about 50k miles ago.  No trouble codes on ecu.  Ambient temp or engine temp doesn't seem to affect it.

Thanks.

Dave
Answer -
David,

Check the distributor for oil.  That is what it sounds like to me.  All the usual suspects have been addressed.  If you take the distributor apart you will find there is oil on the optical pickup and that is what causes the intermittent problem.  The RPM range is a give away.  I would think that a rebuilt distributor will correct the problem.

Von:

I removed the cover on the crank angle sensor and no oil.  Remvoed the degree wheel and all slots open.  Cleaned sensor with cotton swab anyway.  No change.  Next thought?

Why was the RPM a clue for you on your original answwer?

Answer
David,

If the car has a distributor I would check under the cover to see if it has the optical pickup.  If it does check for oil on the pickup and LED.  If not I would be checking the coil for output and make sure there are no wires grounding in the primary or secondary ignition circuits.  From memory the crank angle sensor is for firing the injectors.