NicoRx8

Firstly, cheers Gomez for the info about recalls...

well my car falls in the "thermal damage/ overheating" category !!!

I rang Mazda Australia and they seemed to just rehash a prepared statement that they appear to give all people enquiring about the recall i.e will get letter if affected bla bla, still trying to find out problem and what needs to be done etc !!!! They suck!!!!

Rang my dealer who were "too busy to talk at moment" still waiting for a call back!!!

So I was wondering if you masterminds on this awesome site could help me clarify some things.

I read the info Gomez posted and have some questions

1. Basically to "fix" this problem it seems mazda will reprogramme the inbuilt computer to drop RPM if throttle held above certain RPM levels for a certain period of time to prevent overheating. That right???

i.e default to idle if +8500 RPM for >10sec or +3000-8500 for >2 minutes.

SO the questions I ask

2. will this affect performance ?
3. any problems in future ?
and most importantly

4. WHY DOES THIS AFFECT MY CAR AND NOT ALL RX8s!!!!!!- is mine built with plastic!!!!

I don't know if they are fixing the problem or just avoiding a premature deterioration in the vehicle.

We will see I guess.

NicoRx8

idolo

WTF????? Are these real figures or did you just make them up? Fair enough to the first bit of 10 secs over 8k RPM but i would think thats its likely while on a race track that the car would be over 3k RPM for longer than 2 mins at a time.

Gomez

It has to be parked and over 3K for 2 mins before that mode kicks in idolo.......

NicoRx8

nah....these figures are not whilst driving - only in neutral (i.e clutch down and revving); don't think anyone would keep foot down for >2 min though in neutral, would they???

and they are taken from pdf recall inspection procedure guide posted by GOMEZ earlier today

idolo

OK, well yeah makes more sense, on second thoughts anytime the car is driven on any decent road it usually over 3k for more than 2 mins so der i should of realised that......

BUT

If this is all they are doing it seems a pointless recall. As Nicco says who would keep their foot on the clutch and rev for 2 minutes at a time or above 8.5k for over 10 secs? It wouldn't help dyno runs as the car would be in gear clutch out and would think it was driving.

What car may not experience problems if revd hard while stationary for minutes on end.

takahashi

a hint: dyno.

Speed = 0, and RPM 3-8k for 2 minutes.

xxup

Oh... So the car knows when it is in neutral??

EZZY

but there should always have a fan in front of the car, so there must be some sort of air flow

ned351

aah yes i have had this problem too! Mine occurred late on a cool night chasing a WRX (on a racetrack ) though a number of roundabout chicanes that were spaced approx 150-200m apart. There was just enough distance to upshift briefly in to 3rd at 9000 for a short straight, then have to immediately downshift to 2nd, on to the brakes engaging ABS each time, then drive through the corner at 6000+ in 2nd gear before changing up to 3rd to repeat the process over again for about 10-12 roundabouts.

At the 2nd last roundabout i too had the ECU cut engine revs to 7000 max. For approx 2 mins i could not go above 7000. Not happy i was.

At the next service i asked about this and was told it is an inbuilt protection to basically save the engine etc from excessive stress, blah blah, blah

Dyson Rotary on the Gold Coast have verified this and have told me it is an event that can be reproduced on the dyno.

It can however, be defeated with aftermarket tuning as i'm sure you are all well aware.
cheers
ned351

NicoRx8

now thats weird - so do some 8s have a protective mechanism already built in to prevent overheating - and if it is during driving that sux.

rotarenvy

I would have guessed the rpm cut would have happened to any car that has been on a track. At the Mazda advanced drive-day no cars were affected so it must be a new update?

Gomez

Yes. The manual has a neutral switch on the LH side of the gearbox. The auto has a transmission range (TR) switch on the RH side.

sco

There are definitely software changes for that behaviour to change. No word yet on whether that will be applied in Australia but I expect it will be.

The real issue with idling the car at high speed is covered in some of the other threads on the recall, but in brief - sometimes after jump starting the car, the PCM thinks it detects a fault. In detecting the fault the car goes into limp home mode. In limp home mode, the PCM holds the engine at 2700RPM, basically to allow you to drive the car in case of a fault like both accelerator pedal position sensors failing. So what would happen is people would flood their car, flatten the battery trying to start it then the car would detect a fault and sit at 2700RPM. Thinking that's a good idea to charge the a battery, people would let the car sit still for a while.

Further exacerbating the problem is that if you flood your car then spend minutes cranking it to try to get it to start, the catalyst fills with fuel. So when the engine finally lights up, so does all that fuel in the catalyst. I've heard of the cat getting red hot due to this. Combine that with a long high idle as I've just described then you have trouble brewing.

Also I've hear some of our American cousins who don't have climate control have been known to hold the car at high revs to get the car to cool.

Hope that explains things a bit.

sco

Hymee

iTrader: (1)

The vehicle speed as measured from the drivetrain/rear wheels is still +ve. Onl the front wheels don't have speed. But we have worked around that before.

Cheers,
Hymee.

rotarenvy

but the procedure to bleed air out of the radiator requires you to hold 2500 then 3000 rpm for 5min and repeat. so why should 2700 cause a problem?

sco

Hmm... good point about the air bleed. One would think that procedure would now not be recommended and in fact it will probably not work once we get reflashed.

Don't forget I'm passing on a message... I didn't write it in the first place.

takahashi

That is right Eric, but somehow they suggest a fan in front and a fan behind. too :p