7MGE into 4Runner, Sub-O2 sensor code.

[suprunner]

Hi,

I'm trying to finish up my 7M swap into my 1986 4Runner, and the computer is throwing Code 27. The FSM says that this is the Sub-O2 sensor. . . I didn't have a donor car, only the motor/ecu when doing this project, so I didn't get to see the exhaust. I'm assuming that either/or/both motor/ecu are from a California model... I'm also assuming that the O2 sensor would go after the catalytic converter. Will this be needed? I know that I could: Run without it, and constantly see a "Check Engine" light. Or, when I finish my exhaust, put in another O2 sensor after my catalytic converter. . . Or, buy another ECU, but from a Non-California model... Will I run into fuel-efficiency problems if I just run it as-is?


Thanks,

Greg

 

[bioskyline]

if it is a cali system, according to the tsrm, the 2nd 02 is in the downpipe before the cat
http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?Section=EX&P=2.

i dont see the harm in running without, as both o2s are pre cat, but could always add an extra. maybe you could just wire the sub o2 to the main 02 wires so one sensor sends both signals. im not an expert in emmisions but the 2nd 02 may be to check for exaust leaks that would make the car fail the cali emissions test, due to extra 02 entering downstream?

 

[Nick M]

You could fabricate in existing "MIL eliminators". They produce a constant 450 mv, which is very close to what it should be after the cat. I say fabricate, because they are made for Mustangs and Camaro harnesses. Or get rid of the California computer.