Ok,

Can someone explain how the rev limiter works on the itr?

It seems like it is controlled by the ecu, but what does the ecu do once it decides you are about to exceed the rpm limit it has set?

Does it cut fuel? Do something with the timing/ ignition?

Just curious, because I have heard that on some other cars the rev limiter works even on a downshift...

And I have also heard that hitting the rev limiter causes a lean condition on the itr!?

TIA.

-ken r0cker

Its cuts fuel to the injectors. It is not too good in the fact that it really leans out the mixture

When it reaches the preset rev limit, it goes into fuel cut mode. This cuts off each injector in a cycle to prevent it from going over a specified RPM.
This is a bad way to do it on a high performance engine. For example.. go lean with high compression and BOOM!
MSD utilizes an ignition cut which is much safer. Kills spark instead of fuel. Sounds cooler too. LOL.

Ok, so running into the stock rev limiter is causing my lean condition and thus the whiteness on my plugs? (What I was afraid of...)

I wasn't sure where that lean condition evidence was coming from. I previously thought it was due to the AEM...

Thanks again.

In my GS-R, first, there is the fuel cutoff... but if you keep your foot in it, it'll switch to what sounds like an ignition cutoff (rap,rap,rap)...

The fuel cutoff seems to just be the attention-getter (Ack, I killed the car!) and the ignition cutoff keeps it from over-revving for things like a pulled throttle cable, etc.

Anyone else experience this?

Andy

Unless you have an aftermarket ignition system with an ignition cut built in
then you only have a fuel cut.

Fuel cut isnt as bad as you guys think it is. Its only really bad when you are running
a direct port or single wet nitrous system where fuel is still being injected into
the engine.

As far as your plugs being white, unless you cut the engine off immediately
after hitting fuel cut and then checked the plugs, then you cant accurately
diagnose anything by looking at the spark plugs.

I dont know of a single car where a rev limit will do anything on a downshift.
If the tires spin the motor farther than its supposed to go, nothing is gonna stop
that.

Ok, so what is doing differently when it starts bouncing? There is one big cut and then it starts bouncing much more rapidly. Just the frequency of the injector cut?

At X rpm computer cuts fuel, then when rpm drops to Y rpm then it reengages
fuel. over and over and there is the rev limiter

Yeah, I get that but it's different than, say, a BMW rev-limiter which starts bouncing immediately. This is more like, cut, *pause*, rap-rap-rap...

I dont know where you are getting the pause from.

A newer VW limiter will let the revs drop a few hundred rpm (pause) before the power picks back up. It is not possible to keep the car banging off of the limiter.

I would think that BMW would use similar Bosch electronics... maybe?

Will

New VW's, Audis, and BMW's (and others) have drive by wire, and the rev limiter is alot less violent than in my ITR.

Warren