I've spent many hours pouring through threads about smog on here, 4x4wire and pirate4x4.
Truck is a 93' with a 22re ~ 170,000 miles. Timing is set at ~ 7* (I could dial it back a bit, and it was set with the advance jumped). It has a recent tune up with new plugs, wires, cap & rotor. Failed initial smog on HC's at idle with 617 ppm (didn't give me a complete print out on their new machine, only listed where I failed
).
I put in a new O2 sensor and changed my oil and here are the results.
RPM----------HC ppm-----/-------CO%-----/-----CO2-----/-----O2%
2500 ----- 195 (limit 220) - .26 (Limit 1.2) --- 14.50 --- .6
Idle ----- 1025(limit 220) - .96 (Limit 1.2) --- 15.00 --- .3
With the new O2 sensor (a denso) HC's actually went up (wondering if the new o2 sensor is good?). Obviously I'm running very rich at idle. Would you suggest that I turn the AFM screw to adjust? Also, my rig is running a little rough at idle, almost feels like a miss (when I threw the timing light on it it jumped around about a degree to a degree an a half). It seems to run well off idle though. I'm assuming this could also have bearing on the readings. It hasn't thrown any codes either.
I'm broke right now (just moved and looking for a job) but I can throw a compression gauge and multi-meter on a credit card if you think I should diagnose further (I have access to a FSM but am fairly new at fixing fuel injected vehicles).
Any help is greatly appreciated. Thanks!
