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I'm having a bit of an idle problem. on cold start it idles at 850rpm and as it warms up the revs increase instead of the other way round. So at normal running temp it idles at about 12 to 1300 rpm, but if i turn on headlights or fan the revs drop instead of increasing. The idle adjustment screw is all the way to the slowest idle setting. I took the air valve off and froze it then hit it with the hair dryer & the piston moved about 6 - 8 mm. Also a couple of small flat bits of rubber fell out of it. Am I right in thinking that with the TEN & GND bridged, the ISCV is taken out of play, therefore leaving the Air valve as the likely culprit? I have replaced the TB gasket and the injector insulators.

Any help will be greatly appreciated.

Cheers
Andrew

Hope you solve it.
I am dealing with a similar issue.

Yes, with TEN GND'd the ecu isn't controlling the idle via the valve (IAC)

Check that the little gasket for the IAC - cost $7 from Mazda and completely renewed my idle when replaced.

G