Hi I'm getting a error code 24 for the idle air control valve. Intial tests (from the manual) I have carried out seem to indicate the valve is ok, before I look at sourcing another is there anything else that can indirectly cause the error code 24 to occur.

It's 94 WRX engine with W6 ECU, 3" decat exhaust, FMIC, and Pipercross cone filter. Wondering if any of the above can cause the error code 24 to appear for the Idle Air control Valve

Cheers
Guy

 

are you using a 94wrx throttle position sensor?

Simon

 

Simon, the engine's fitted in my kit/replica I previously PM'd you about. Got it on the road last week and and just starting debugging it.


The Throttle Position Sensor is what was on the donor car (jdm 94wrx saloon) from Grade-A.

Engine is stock apart from the mods mentioned, necessary to fit it in it's new home.
The VSS signal is being operated via a later gearbox sensor rather than a speedo one, but am getting over 4500rpm so guess it's working.
The blue 2 wire Throttle Pedal Switch that normally lives up by the accelerator pedal under the dash is not connected,
and nothing is connected to the aircon wiring lines from the ecu, as no need for aircon

Engine temps wise gets up to temp and just sits there happily. Getting boost etc. Just getting this error code 24, which seems to come after driving slowlyish say 30-40

Guy

 

is the sensor a 4 wire one?

the early 4wire tps have power, ground signal and idle signal.. if therefore it is only a 3wire one and you altered the wiring (cannot remember) then this maybe why it gives the code.

other reasons could be the tps is positioned wrong so at small throttle openning the ecu is trying to go into idle mode and cannot get the idle under control so then trips the code.. maybe worth moving the tps sensor clockwise a tiny bit.

the idle valve is unlikely to trip a code if the idle is actually fine..

the throttle pedal sensor is code 45 from memory? but just records in the ecu and doesn't light the CEL.

Simon

 

Will take a look Simon, think it's a 4 wire from memory.
When I modified the loom I trimmed nothing down that went to the engine itself as some is shielded cable and a pain to trim and still avoid signal interference, it was as easy just to route the loom "artistically" around the engine bay anyway. Had to lengthen some wires and shorten others but managed to avoid to the engine itself. In a past life I used to wire machinery so am ok with the wiring side of things.

Engine seems to pull fine apart from that, 240bhp+ in under 750kg it should do I guess