1990 supra n/a idle problems

[cre]

Originally Posted by Scraperondubz

the resistor pack on the driver side near the shock tower is missing

Originally Posted by cre

I just noticed you're mention of the resistor pack... if you mean the injector resistor pack, 89+ N/As run high impedance injectors and as such do not use this. If you're referring to the fuel pump resistor and relay then yes, it is possible that you are running excessively rich.

The missing resistor pack isn't your issue. If you had low impedance resistors and no resistor pack the injectors' coils would burn up... but 89+ N/As all have high impedance (denoted by the green tops (which, sadly, sometimes do fade to a yellowish color)).

So this issue is only happening when the car is going into idle? I'd continue working on the code 14 (wiring and ECU remain suspect if the igniter and coil are good) and also check the Coolant Temp Sensor, ISCV and TPS when the engine is hot. Try checking the diagnostic codes when the engine is hot as the code 51 is not a stored code.... it clears once the error condition is no longer present.