To josh or anyone else, my 93 legacy automatic is giving error code 42, just started now that the temp is below 35 degress. Car runs fine and the idle is at 800 or so. Do I wait for any symptoms and just keep driving?

thanks

You may want to check the TPS. The idle switch is built into the TPS.

 

This procedure tells how to set/test the idle switch

http://www.main.experiencetherave.com:8080/subaru_manual_scans/FSM_Scans/TPS_testing3.jpg

 

If you test it and it tests ok, or if you readjust it, and the CEL doesn't go away, you may need a new TPS.

will test sometime in the next week. I reset the ecu and the code hasn't come back in the last day. I 'm the guy who put the (1990-1991) 65k motor in a 93 legacy (378,000 now). Had the tranny fixed and still am getting 21 mpg on the highway and 15 mpg in the city (was getting up to 30 and 23 before engine swap) totally stumped. Plugs are not rich looking.