Help please...AYC Problem

[vr4terry]

Hi there,

When moving off from standing still the ayc will light up with one green light and then go out....is this normal....if its from a junction (after driving) sometimes there can be 3 lights on with a clonk from the back but then they will go out and car will drive normal. Red AYC light has never come on.
Also one green sometimes three greens will come on with clonking if I reverse.

Another thing....car seems to surge/hunt on idle (sounds like it is) but will sit at 650-700 rpm all day on idle when warm. When cruising will splutter/hesitate at 2000 rpm in 5th but when given boost will accelerate normally.

I have replaced the plugs, leads and idle control sensor. I have purchased but haven't yet fitted a brand new emission control solenoid valve and plan to replace all the vacuum lines.

The car is standard apart from a full 3" fujisubo exhaust system with de-cat. 1st 02 Sensor is still fitted. Wheels were recently changed from 16" to 17" but problem was there before the wheels were changed.

Any help would be grateful.

[Nick Mann]

Does the red ayc light come on when you start the car? Like the airbag light, engine check light etc.

A boost leak test would be worth doing too, lots of little issues can be caused by little boost leaks.

[vr4terry]

Does the red ayc light come on when you start the car? Like the airbag light, engine check light etc.

A boost leak test would be worth doing too, lots of little issues can be caused by little boost leaks.

Yes red AYC leak goes come on when ignition is turned on along with engine, srs etc and then all go out as normal.

Will be replacing all the hoses boost and vacuum anyway so hopefully will cure it.

[TAR]

'Clonk' sounds mechanical. Mechanical things associated with AYC are - AYC pump, rear diff, abs sensor rings on drive shafts.
Other things that can make the AYC light up are - unequal tyre pressures, unevenly worn tyres across an axle, rear brakes sticking on.
:happy: