Over the weekend, my car clocked 10,000km sometime on Saturday. I didn’t really drive it on Sunday.

This morning when I started it from cold, it didn’t do the usual jumpy 2,000+ RPM idle like it normally does for a few seconds, but rather a gentle 1,200 or so RPM smooth idle. The ambient temp was 27.

A 10,000km odometer switch perhaps – leaner mixture/lower RPM for starting?

I really need to see if it does it more than once, but it was immediately noticeable. Might have just been a random coincidence.

Was wondering if other "old-timers" have noticed same?

Cheers,
Hymee.

 

Coincidence I suspect. I've heard speculation of a 5000km switch, 15000km switch, 15000 mile switch, etc, etc. I haven't heard of a 10000km one yet. It would be nice though, because I should hit 10000km on Christmas day at the rate I am going. I'll report back if I notice anything.

 

All RX-7's had them so I would say yes.

Will find out for sure though

 

I've read speculation about this, too, but as I suspect I have the longest odometer reading, at least in the Australian form ( it's good to claim I might have the longest something in this forum, what with L&L around :D ) … now coming up to 18,000, and I can't say I have noticed any major change at any of these way points; I certainly still get the "usual jumpy 2,000+ RPM idle" at start.

However, Jon Waterhouse from Reliance Rotary here in Canberra, who does my interim services says he feels the motor has really loosened up a lot and feels much more powerful than those just off the ship -- and he's certainly driven it at new, 7.5k, and 15k, as well as other 8s. As I'm in it every day, I guess it's unlikely I'd notice any gradual change.

I have noticed my fuel economy is slightly better (even with more a/c use in the warmer weather), but my recently diminished licence points may be a factor there :p

Does anyone have any facts on either ECU km switches or the "learning" ECU other than the speculation I have read elsewhere?

From a programming perspective, it would certainly be possible to do, but why/to what effect/what happens to cars that have different driving patterns?

-----
Maestro, my post crossed yours, so any info you can collect would be gratefully appreciated -- I even promise no sheep jokes

 

I've just had my 20,000km service last Friday and I'm pleased to say she's running sweeter than ever.

 

Oooooh, timbo has been topped

Some days, I swear it feels fantastic, other days... perhaps not so supercar like... one thing I know it likes is air temps around 13' ambient, always feels like a rocket then! :D

 

Yeah - cool dry air is always sweet. Bit hard to find 'round here at the moment

 

Hymee,

In an earlier post I talked about increased power after 5,000klm.
In retrospect I suspect it was just a nice cool evening with dense air which promoted good power on that particular occasion.

I suspect that the RX-8 ECU does not have a flip at a certain number of kilometres as it is a "learning" device and it relies on constantly monitoring the data it is getting fed from the engine. No doubt as the engine loosens up it will lean things down a bit. I think that we are probably slowly getting more power as the ECU determines that the engine can take it.

I live in hope though!

 

ECU re-learning normally takes minutes certainly not months.

As for a mileage switch - I dont think anyone will ever know. People only know about the rx-7's because there is a seperate wire that runs from the odometer to the ECU that becomes active once a certain mileage hase been reached. The RX-8 odomoter data is held by the ECU and the display on the instrument cluster is updated by CAN data from the ECU. Thus, any "switch-over" will be triggered by a target number of pulses within the PCM being reached, not anything you can see on a wiring diagram.

Short story: Nobody will ever know.

 

RPM_PWR

I was not suggesting that the ECU takes months to learn. I was saying that unlike previous generations it does not need a flip at a certain mileage as it is constantly adapting to the conditions it is encountering unlike earlier ECUs which need this switch as they were not constantly being updated with engine condition information on the fly.

This is only my theory based on the information I have got from this forum and I stand to be corrected.

Regards,


Steve

 

My 10,000 incident was indeed not repeated this morning. Ah well. Must have been a purely random event.

Cheers,
Hymee.

 

It was a hot night the night before. Probably only got down to the low twenties as a minimum.

 

They were- it was just bad information :D You might well be right with your theory, sorry for the confusion.

-pete