Question for you guys as I am a little worried.
I have noticed that the VTEC step on my car had all but dissappeared it is an MY00 with 30,000 miles on it. I also noticed that (as a test) from cold I revved it from standstill and there was no rev limiter cutting in and it would have gone all the way round to 9000rpm. It also ran badly at idle but a few times on one trip but all is ok here too. So I have been to Honda they say it is ok they changed the oil and tested the ecu for error codes there weren't any. There has been no lights on the dash - I have not over revved it or mis shifted. Honda drove it and confirmed that it was all ok. I have driven it since and the VTEC is back but not quite the same as it was before. I also tested the cold rev limiter at 6000 and again it carried on.

So my questions are why is this rev limiter not working?
will the 9000rpm rev limiter cut it even if the 6000 one doesn't? - I don't have the bottle to check it.

Any help would be great

Cheers chaps

Rob

 

Sorry chaps I am really worried about my car and need some help - unfortunately I have no mechanical knowledge at all and so feel well out of my depth in this forum - you guys are talking another language most of the time. Honda say my car is okay and I hope / believe and trust them but surely that is foolish - right!

Think that I will take it back to Honda and ask them about my rev limiter

 

There is no "cold rev limiter". The only thing you're accomplishing by revving a cold engine to 9k is ensuring a quick death.

The "cold rev limiter" you're mistakenly referring to is simply a VTEC limiter that won't allow VTEC to engage if the engine isn't warmed up to 3 bars. That doesn't mean the engine won't run all the way redline.

And yes, there's an actual rev limiter at 9000 rpm or so. I really suggest you don't bang off it on a cold engine

 

heffergm, you are in correct. There is a cold Rev limiter. The ECU will not let you rev past 6500rpm when the oil/coolant temps are below a certain temperature.

Why anyone could care to rev their engine cold anyways ....gets me????

 

not only is it bad to rev a cold engine to 9k, it is also bad to rev even a warm engine to 9k at a standstill with no load. A combination of both is very bad. Tugz is right, however, the engine does not let you rev up based ONLY on coolant temp (meaning how many bars you have on the temp gauge) It takes longer for the oil to reach operating temp so give it at least a few minutes of driving with 3 bars before you rev the heck out of it.

 

It can take over 20 minutes for oil to reach optimum temperature. And what does that mean, exactly? It has to do with the anti-wear and anti-friction additives, which do best when the oil is at least 200 degF.

Plus, any racer knows that the engine should be good and warm before anywhere near 9K is attempted - all those different metals expand at different rates, and the engineers go for the normal operating temperature when spec'ing tolerances. In engineering it is known as homeostasis - on the street, it is known as common sense. Let your baby get good and warm before you jump on her.

 

Right it all seems pretty good now I have covered a few hundred miles in the last few days and the VTEC is just right. I still do not have the lower rev limit when cold but will not try it again. don't /won't have the balls to check the upper red line limiter

 

I believe the "cold" rev limiter is tied to the vehicle speed sensor. If you are not moving, I think the ECU will "let" you rev it past 6000 rpm - NOT a real smart thing to do to a cold engine and NO LOAD, but you've heard this already, right?
The degree of VTEC "kick" is dependent upon several factors, some of which include oil viscosity used, oil level, throttle position, which gear you're doing it in, etc.
If you are not mechanically inclined, you should not be testing things like this out on your car. I'm talking about revving the crap out of it when cold, sitting still. You should perhaps get some reading material and learn some basic automotive knowledge before finding things out "the hard way". The next thing you "test" out might not end up so well.

 

, it surprises me how people lack common sense. i see far too many people daily that just turn on their cars and rev the crap out of their cars. doesn't matter if its a s2000 or pinto(well who cares about pintos) but anyways, yeah you need to give your engine time for the oil pressure to reach operating temp. its like a jogger in the morning, he won't just wake up and start doing sprints. he's bound to pull a muscle, same deal with an engine.

 

[QUOTE]Originally posted by Road Rage
It can take over 20 minutes for oil to reach optimum temperature. And what does that mean, exactly? It has to do with the anti-wear and anti-friction additives, which do best when the oil is at least 200 degF.