Hot Start Fix
 

Has anyone used Mazdas new plugs for a hot start remedy yet? I order a pair. They are supposedly much hotter plugs to insert in the Lead plug spot. Wondering if anyone has tried them yet, I just came across them. Hadn't seen them before.

More?

wut?

the hot stare issue is a sign of bad compression, plugs will not help...only premixing can save you now.....lol

What is it? Never heard of it...

These plugs which Mazda made to remedy hot starts do not make much of a difference. I purchased a pair (you buy them in a set of 2 for the lead position) a long time ago and they made no more difference then having fresh plugs (well, and that they were more expensive too). I want to say the plug part number was the 1 ending with a 9.

Regardless, I saw no big improvement and swapped them out when winter came with fresh plugs and saw no starting performance drop. But maybe if your engine is healthier than mine it will make a bigger difference; Not sure.

I was told this is absolutely not the case by a rotary head (who has RX7 and RX8 owners visiting him as if he's Rotary Yoda).

He said "hot start" issues are more likely to be indicative of spark plug/wire, starter motor or battery issues than anything else, in that order.

(I can see the spark plug/wire and starter motor logic, but the battery suggestion throws me for a loop).

I'm not claiming he's correct or incorrect, but the guy knows more about rotaries than anyone else I know or that I've met.

Well, if I may ask, if you've made up your mind why are you asking? You obviously have decided he's correct because you've dismissed the replies you're getting here.

I'd say buy the plugs then let is know how you're hot start problems were cured! All the people that have had to get remanned rotaries here will love to hear it.

Read the last sentence of my response above.

I was merely reporting what he had told me.

FWIW, my 8 would take longer to turn over when warm/hot for the first 2 1/2 years, and when Mazda replaced the starter motor and battery (from a Panasonic to an Interstate) under a TSB free of charge, the problem went away.

Again, I'm not saying this couldn't have been coincidence, but it would have been an odd coincidence.

Hot Start Plugs
 

Well, it appears that it really did not help the problem. Just so everyone knows. It did runs a little better because the old plugs needed changing, but still have hot start issues.

And that's exactly what we said.

Hot start problems are caused by weak ignition coils, feeding into leaky spark plug wires, that then fire fouled worn out spark plugs, into a combustion chamber that doesn't have enough compression, spinning at too slow of a speed.

Having a hotter grade of spark plugs helps absolutely none of those issues.
But it does allow the dealership to charge you several hundred bucks, and gets the mechanic who worked on your car an extra tank of gasoline that day.

BC.

Sorry guys, and Sorry RadRed & Bruce - Bladecutter just reminded me IT WAS bad coils that were causing my hot start issue -

- the dealership replaced two of them (I think) at the time the starter motor and battery were replaced.

I had completely forgotten about that.

Before getting those replaced, the motor was misfiring at idle and having longer starts when completely warm.

I had hot start issues for about 4k miles. Then under normal driving the Apex seal came apart. Just my 2cents

the hot start plug is better for city driving because it can retain heat longer than stock 7 heat range plug. So it will less likely to foul. but you will lose maybe 1% of hp which ur butt dyno will never notice

another problem is that u can only get these plugs at mazda, ngk, for some reason dont offer them as aftermarket plugs

Just to highlight our different experiences, when my battery, coils and starter motor were replaced (the one and only time I've had any non-regular maintenance done; my 8 has been rock solid), my odometer had 68,000 fewer miles on it than now, and my motor is literally as strong as ever.

Are you certain about it, nycgps? I'd like to know, I may just look into purchasing those plugs since I drive mine in the city 80% of the time.