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High idle on MPFI

Featured Replies

Cant seem to adjust the idle in the ea81t to below 1000 rpm...... the adjuster screw is undone completely.

Not sure what is causing it, but i suspect the auxiliary air valve?

The valve has had its top (black plastic) snapped off at some stage, and has been glued back together. Would a hole in the glue cause the engine to rev higher than it should even when the engine is warmed up?

If anyone has a diagram of the inside of the aux air valve it would be nice.....!

any ideas?

cheers.

Cant seem to adjust the idle in the ea81t to below 1000 rpm...... the adjuster screw is undone completely.

Not sure what is causing it, but i suspect the auxiliary air valve?

The valve has had its top (black plastic) snapped off at some stage, and has been glued back together. Would a hole in the glue cause the engine to rev higher than it should even when the engine is warmed up?

If anyone has a diagram of the inside of the aux air valve it would be nice.....!

any ideas?

cheers.

 

Sounds like you are using the throttle stop screw rather than the idle adjusting screw. The idle screw is a vertical brass one that will be turned in for lowest rpm and out for higher.

 

A leak at the AAV may cause a high idle.

the aav valve introduces a "false vacuum leak" when the engine is cold, and then closes off as it warms. if it is not functioning properly it may still be introducing a leak.

 

run the motor till its warm and try punching off the hose that leads to the intake manifold, and see if that changes the idle.

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