Problem #7
On rare occasions I get code 67 (neutral pressure switch or clutch switch circuit failure) when doing a KOEO test. This of course prevents me from doing a KOER test as well. The code usually goes away fairly quickly, but I read some discussions on how code 67 can cause a surging idle. The transmission in the Jeep is a manual with "granny low" from an older Ford F-150 or F-250. There don't appear to be any wires coming out of it, so I'm not sure what occasionally causes code 67 or how to troubleshoot it.
This tells me the EEC is for a manual mustang. Still, i'd find it and runthe numbers to confirm.
On the Mustang, there is a harness that connects to the top of the transmission to indicate neutral, as well as to the clutch pedal. usually to run the codes requires the clutch to be pressed in, and the trans in nuetral.
Who knows if this was wired correctly in this case. This is rumored to cause idle surge issues, but hasn't been confirmed. Worth investigating how this circuit was plumbed up.