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EricSilver · #40 05-15-2009, 11:08 AM

I think this will turn out to be an NSS-related problem.

As previously posted, when I replaced the old one the new one was misaligned but I ignored it. It would start in Park if I moved the shifter it a tiny bit to the right, and in Neutral if I moved the shifter a bit forward.

In the year and a half or so since I replaced the NSS, the misalignment has become more pronounced, requiring a somewhat longer rightward movement of the shifter to start in Park. I also discovered yesterday it will not start in Neutral at all – unless the car is warm (not hot, not cold) and I cycle the shifter all the way to 2, then to N, in which case it fires right up (in its normal position). I did this successfully several times to make sure it was not a fluke.

In reviewing my notes about the NSS, I saw a comment taken from member JimF’s site which said the NSS has ohmic switch contacts. If its ohmic it can be temperature sensitive and all the temperature/weather-dependent ASR fault issues I have been experiencing, and which I previously attributed to the ohmic ECT sensor, now made more sense when blamed on the completely weather-exposed NSS.

This morning I cycled the shifter several times from 2 then N to see if the car would start in N when cold, but it didn’t. However, after starting in Park, the ASR fault vanished in about three minutes, instead of the usual 5-7 (or more). Also, when the ASR fault has normally appeared, restarting would trigger limp mode immediately. Today, after shifter cycling and restarting, limp mode did not occur until after I backed out of the parking space I was in, and hit the brake. I don’t think this points to the brake switch, but rather a conflict between its signal, and that of the NSS.

So, NSS alignment is my first priority. It is as Febi switch, not OEM, so I may need to also replace it with a new OEM one in case the switch itself is faulty.

EDIT:
Also, the time span over which the variance in required rightward shifter movement increased corresponds precisely to the time span over which the low temperature ASR fault threshold has risen. In the beginning, the ASR fault occurred only in sub-freezing weather. After replacing the switch it started occurring in progressively warmer temperatures, towards its current threshold of about 55 degrees. The further misalignment is probably not natural, but more likely a result of me nudging the shifter farther than necessary when starting the car.