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Blueskev · Alfasud Joined: 12 Jul 2012 Posts: 33 Location: Kent

Im keen to check the timing on the ie to see if it is causing the poor low speed running (clutching at straws really, I think a compression test will show all is not well...)

What should it be, and under what conditions should it be checked, vac advance connected/disconnected etc?

Many thanks,
Kev.

LoneWolf33 · Posted: Thu Oct 03, 2013 8:44 am Post subject:

Hi,

Poor running at low engine speeds could be caused by vacuum leak,
defective lambda sensor, or just the idle speed is set too low.

To test the basic ignition advance the hose must be disconnected from vacuum advance chamber.
I'd recommend to seal the loose end of the hose.
If your 33 is manufactured between '90 and '92, disconnect the throttle position switch connector
as well during the test. (This will provide fixed advance value below 1050 RPM).

You can try to disconnect the signal wire of the lambda sensor at warm/hot engine,
to see does it makes any difference.