RX8 difficult to start when hot

[was8v]

Mate has an RX8 that starts on the button when cold.

When hot (e.g. after filling up) it takes over 30 secs of constant turning over before it fires up.

This is after its properly warmed up (he is aware of short trips flooding).

Will a new (allegedly faster) starter motor fix this?

Edited by was8v on Wednesday 28th July 12:21

[was8v]

Wadeski said:

I think this is a classic RX8 problem? probably a FAQ on the owners club...

Yeah, the classic answer is "faster starter". But I'm not convinced- the old starter spins just as fast as when it was new, so my thinking is the root cause is elsewhere.

Badrotorfinger's experience supports this.

[was8v]

Hi guys thanks for all the replies.

How would I go about testing the coils - or is it a case of "suck it and see" and buy new parts?




I had a corrado VR6 with a failed coilpack once, it used to missfire when hot, I just swapped it for a new one but it showed no visual signs of failure.

[was8v]

wolves_wanderer said:

Or about £250 for coils and leads if you don't mind doing it yourself (very easy even for a mechanical halfwit like me)

We pulled the existing coils to inspect. They are all very very slightly discoloured in the middle of their bottoms. No white spots just slightly discoloured.

The bit of engine they touch had a corroded patch in the middle of where the coil touches.

Apparently the previous owner told my mate the coils were replaced a few thousand miles ago- no confirmed date or mileage as there is no receipt. The coils do not have a Mazda logo anywhere. The PO no longer answers the phone to my mate (odd, he just wanted him to confirm the date/mileage they were done to eliminate the coils).

Edited by was8v on Wednesday 4th August 08:35

[was8v]

nottyash said:

My Dad has just bout the coils for his on the net from the good old USA for just £128 delivered. About £100 cheaper than the cheapest aftermarket UK ones (Same company in fact)

Any chance of a link to the site he bought from? Cheers.

[was8v]

lilwashu said:

I would not spend any more money on the car before getting a hot compression test done at a rotary specialist.

Plan is to do a hot compression test at the weekend.

Anyone know the figures for a healthy engine?

[was8v]

Thinking about the way a rotary engine works, my conventional pressure tester will only give the overall max compression, rather than the value for each tip. Also there's little point in moving the tester between plug holes.

Some people suggest removing the relief valve from the tester and watching the needle bounce for each rotor tip.

Hmmm. I suppose a basic test using my tester this way may indicate if there's an issue. This will perhaps rule out the coils.

If compression is a little low then the newer faster starter (which by nature creates more compression) may fix the issue. This seems a bit of a bodge by Mazda to me as surely eventually the tips will wear meaning the thing needs an even faster starter......