Mark A

iTrader: (1)

ECU error messages has appeared with the above problem.
Can someone please explain what this valve does & how its works
Is this a common problem & easy to fix ?
The car is a early 94 WRX with minor mods, airfilter,down pipe & exhaust.

jack

Mark, try lots of carb cleaner into the "feeder" pipe (while you keep the engine running) for a start. Should remove all the gunk stuck inside that might be causing the problem.

Mark A

iTrader: (1)

Is there a connection with above & also an error code for vehicle speed sensor2 as they both came on @ the same time.

jack

Don't ever recall one common cause for both these codes before....

Mark A

iTrader: (1)

Ok took the stepper motor off the valve & it turns no problem, disconnected the lead to valve & engine tries to dies.This must mean the valve is working.Reset the ECU and both error messages return(24 & 33) air idle solenoid & vehicle speed sensor 2.

Anybody got any britgh idea what these to messages together mean?

Is VSS2 on the gearbox on in the speedo?

Stephen Cole

Well I definely (99% certain) got code 33 when my speedo cable broke, so I would say VSS2 is the speedo input

Although I would have thought that was VSS1
(if there is such a thing)

Some other people claim to have seen a VSS2? cable coming out of the gearbox, but I think they are mistaken

PS There is another VSS or rather deceleration related sensor, on the chassis (horizontal) down near the exhaust downpipe, which I think is a decerormeter for the ABS


Stephen

Ricky Budlight

Mark

When do you get this error as my 93WRX seems to have the same problem....I only get it thou when i boot it and this in turn makes the engine idle very erraticly and the "Check Engine" light appears...if i leave it and go at a steady mph it seems to clear the fault..i have changed the idle air solenoid but the problem is still there..its only when i put me foot down which aint no good if i drive a Scooby..!!!!!!

Ricky

Mark A

iTrader: (1)

Ok that might explain something,

I had the speedo out to change the kph to mph.
I wonder if I've not fitted it back correctly.

Any idea where on the speedo the speed sensor is located ?

Steve Lawson

Hi Mark,

The speed sensor is located on the back of the head,check you tightened all the little philips screws on the circuit board.
The two fault codes you are seeing are quite common is it actually putting on the check engine light?
Usually you see the speed sensor one because of uneven tyre wear front to rear or the sensor just gets confused.
The idle speed control valve also gets a bit muddled from time to time,best thing to do is to clean it out as Jack previously mentioned.

Steve

Mark A

iTrader: (1)

Reset ECU & drove the car, after 10 mins engine check lights up & stopped car checked codes, both 24 & 33 displayed.

Steve do you know why the idle valve error occurs, is it because the valve can't open or close fully(the engine dies when the lead to the solenoid is pulled which I presume means its sort of working)

re code 33 brand new wheels & tyres but like I said had the dash & Speedo in a thousand bits, but it is working @ 100% accurate according to SVA centre. Best check it again.

Thanks for continued input.

Mark A

iTrader: (1)

dash & Speedo in a thousand bits,

And only put 999 bits back, sure enough Mr Lawson your where right,1 small screw missing from the rear of the unit. This years award for worst subaru mechanic goes to Mark A.

Dismantled idle valve & cleaned with carb cleaner. ( put all parts back correctly, I think)Reset ECU & no more error messages so far.

Thanks again to everbody who helped.