First sub-zero cold start - HIGH revs?
#26
Rotary Superstar
Join Date: Jul 2005
Location: Maryland
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Originally Posted by rotarygod
This is one of those issues that rotaries have always been set up to do. However it doesn't mean it's good for the engine. It isn't. When you first start a cold engine you don't really have an oil up in the engine. It's mostly in the pan. You start it and it takes a few seconds for the oil to reach every passage and bearing. It definitely isn't a good idea to spin the engine up faster right away during this period. It adds a small amount of wear to internal parts. The next thing is that you don't want the engine heating up too quickly as we have staggered cast iron and then aluminum housings which expand differently with temperature changes.
So why then does Mazda do this? Emissions! That's right, an environmentalist beaurocrat somewhere had enough of a say that it affects the longterm wear of your engine! Emissions standards say that your cat has to do it's job within so many seconds of starting. It can't do this when it's cold though so they need to heat it up as fast as possible but still slow enough not to kill the engine. A little wear is fine apparently. The engine revs up higher when it's colder because the cat has a greater temperature range to heat up to. They need the extra heat out of the engine. Thankyou EPA.
The RX-7's were done mechanically rather than electronically. We used to disable them and just let the car take a little longer to warm up when cold.
So why then does Mazda do this? Emissions! That's right, an environmentalist beaurocrat somewhere had enough of a say that it affects the longterm wear of your engine! Emissions standards say that your cat has to do it's job within so many seconds of starting. It can't do this when it's cold though so they need to heat it up as fast as possible but still slow enough not to kill the engine. A little wear is fine apparently. The engine revs up higher when it's colder because the cat has a greater temperature range to heat up to. They need the extra heat out of the engine. Thankyou EPA.
The RX-7's were done mechanically rather than electronically. We used to disable them and just let the car take a little longer to warm up when cold.
And that pesky little thermowax pellet in the front of the e-shaft..why don't I see more RX8 guys shim that, like we do on RX7's? I know I will be doing just that, as soon as I have money for an Agency pulley..
#27
[B]last week my 8 did the same thing on a few mornings in a row where the temp was in the single digits. yesterday it started but began to shutter, misfire with the CEL now on. the car has no power and will not move when put in gear. it would'nt even make it up the flat bed when it was picked up. It is on its way to the dealer. it has 12,000 miles on it.
NOT GOOD !!!!
NOT GOOD !!!!
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