After having the car MOT'd on monday I've keep getting the fault code of EFI-233.
The first 2 are not worth worrying about but the EFI-233 adaptive idle air trim is the one that is putting the lambda light on. So with a bit of research on the internet I came across this.
"Diagnostic trouble code (DTC) information EFI-233
Substitute value idle air trim disabled fuel shut-off conditions changed output signals to the coils are regulated with a fixed value depending on the cause of the fault leakage diagnostic is disabled. Possible source
Signal too high: short-circuit to supply voltage in the signal cable defective idle air control (IAC) valve.
Signal too low: opening and closing coil signal cables short-circuited to each other defective fuse 11B/2 (1998-) open-circuit in power cable short-circuit to ground in signal cable defective idle air control (IAC) valve contact resistance in terminals.
Signal missing: open-circuit in signal cable defective idle air control (IAC) valve contact resistance in terminals.
Fault symptom[s] idling speed low or high."
As I'm not getting a signal to low/high or missing I'm little puzzled on what the fault could be as the IAC has been running trouble free years.
So rooting around in the Bin I came across a RPM/throttle angle boundary for ZWD off (IAC valve) as you can see in standard form the IAC is still in use upto 3390rpm and 47.30 degrees on the throttle. So I've lowered both values to 1980rpm and 19.98 degrees on the throttle.
I'll upload the new values on the ECU tomorrow and see what happens.
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