Bambam7

I'm sure the geniuses at Mazda have the foresight to avoid this problem, but it just occured to me as I was wondering why premix engines have gotten the rep. to have much less wear inside..
OK- The S5 OMP is controlled by a plunger off the TPS. The more throttle, the more oil is injected.
BUT What about high rpm downshifts??? I do it all the time- I regularly let it rev down from 6000 rpms to idle... (OK, it sounds cool) and it saves brakes...
Is any oil getting injected during this period of 0% throttle position, yet 6000 rpms???

dre_2ooo

Nope, it runs at idle settings... both fuel and oil. Premix doesn't help either here. I'd rather wear brake pads than apex seals (shift to N).

There was already a thread on this a while back....

SaabGuy

Wow that is the simplest reliability thing we can do every time we drive.

I really never thought about it. I also never really downshift, but on the highway you know people cruise a lot with their foot off the throttle.

Thanks! I'll probably get another few thousand miles out of my motor now.

hanman

Downshifting doesnt' help much in a rotary anyway. Not enough compression.
hanman

peacekeeper

so should we do pre-mix or no?

NZConvertible

Where did that little nugget of misinformation come from?

NZConvertible

At zero throttle, the fuel injectors are shut off until revs drop to below 1500rpm.
I highly doubt the MOP does this though.

Bambam7

OK- this isn't a thread about running premix.
Anyways.... well, that's not good news. I spend a lot of time at mid-rpm with no throttle.
That's going to change. I can't beleive that very little oil would be injected no matter what the rpm. Well, hopefully the idle setting as at least to prevent major wear...

dre_2ooo

Yeah, at zero throttle the OMP runs at idle setting. Just look at the mechanical linkage in an S4, when you let off the gas, it snaps back to the position it's in at idle.

Same goes for the S5 ones but it's electrically monitored. Get a measuring cup if you dont beleive me.