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Old 07-02-2010, 03:22 PM   #18 (permalink)
some_other_dave
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I read in one of the 1990 CRX manuals (either owner's manual or workshop manual, I don't remember which) that the CRX shuts off the injectors when the throttle is closed and the RPMs are above 2500. I am pretty certain that I read it in one of the manuals, but I have looked for the info again and have not found it.

But yes, as others have said--when you're coasting in gear, the turning drive wheels are causing the engine to turn, so cutting off fuel doesn't kill the engine. You might be able to kill it if you enter DFCO and push the clutch in, but it's also possible that the ECU will see the clutch action and start the injectors again, or that starting them up again at whatever the lower RPM bound is will get the engine running on its own.

I have heard rumors that the earlier carbureted Civics would also shut down fuel flow on overrun (coasting with throttle closed, very very high manifold vacuum), but haven't seen any documentation of it. It would be cool to have a reference for that. Those Honda automotive carbs are hideously complex things; it wouldn't surprise me at all if they have provisions for that.

-soD
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