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Is it possible to adjust the fuel mix at idle? -

I don't think I'm talking about the idle adjustment screw, which I understand is throttle related -

I'm talking about adjusting the fuel mix - mine seems to be running rich after the new motor install.....

Any assistance available?

you have a piggyback for fueling don't you? wouldn't that be adjustable ?

yes and no...

You can tweak the air flow meter (at least you can on a 1.6 with a hidden screw) to alter the meter output signal at idle, hence the fuel mapping will change.

However, with the O2 sensor warmed up (ie, engine not cold), the ECU will operate closed loop and bring the mixture back to stoich.

Matty wrote:yes and no...

You can tweak the air flow meter (at least you can on a 1.6 with a hidden screw) to alter the meter output signal at idle, hence the fuel mapping will change.

That will be the hidden screw under the raised metal cap????

The issue is that the car idles ok initially (when cold albeit with raised revs) and then slowly startts to fail - it did it this morning and I could smell the fuel, so she's rich. I also had to wait a little bit for it to start again.....

There's some info on the web here and there about the idle control valve - I'm presuming that's the 'attachment' on the engine side of the plenum on the 1.6?

I'm thinking with it having been off the car for a while it may be sticking - anyone here got any experience with checking/fixing this part too?

Yes it is under a little metal plug. To remove this just drill a small hole through it then screw in a self tapper and use this to pull the plug out with.

I'll get a pic tonight if it helps(and I remember )

Tim