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2007 Mazda RX-8 — rev up before turning off?

I replaced the engine on this car in 2017; want to keep it forever. What is your advice about reving up the engine before turning off? dealer says i should do this to burn up excess gas and prevent flooding but have gotten conflicting advice. Thank you.

Don’t listen to the dealer.

The engine is computer controlled.

Drive it as if the engine was never replaced.

Tester

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Who at the dealer says this? A certified mechanic?
I think not!

If you want to avoid excess gas etc. always run it enough to warm up the engine before shutting off…without revving up.

I’m not that experienced with Wankel engines (drove an RX-3 for a couple weeks while my brother was out of town), but if the modern fuel injected version floods with fuel then something is wrong!

The rotary engines do require some special care that normal engines don’t. In my experience you don’t want to shut the engine off immediately after starting it, as it may not easily restart. I found this link which describes some of the best practices to use.

Now here’s the real question?

Who the hell would own a vehicle where the engine must be pampered in this manner?

Tester

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People who drive sports cars. I remember the pre-turbo-timer days. If you drove spiritedly and had a turbo, you had to sit there idling for a few minutes before you turned it off to avoid coking the turbo. Royal pain in the butt, but… Turbo.

My bigger problem with rotaries is that finding people who know how (and are willing) to work on them is a lot harder than with a normal engine that does not run on witchcraft.

I expect revi’ng the engine slightly as you turn it off won’t cause any problems. So since the dealership shop says to do it, and they are the experts, might as well just do what they suggest. It’s not much of a burden. I don’t have an explanation for why that’s necessary, but I have no experience with that engine either.

These engines are known to gasoline foul the spark plugs or “flood” when operated for a very short period of time. If I had to move this car across the parking lot I would operate the engine at 2000 RPMs for 30 seconds, then return to idle before shutting it off. To “rev up the engine before turning off” seems rather vague, I question if the OP understood the instructions.