[OliOC]

So I just want a bit of reassurance I haven't done any long term damage.

Took a friend out for a quick spin earlier, got the engine warm then thought I'd put the 'box in sport mode (auto) whilst having the car also in sport.

Excellerated off an a road onto A quiet B road and must have accidentally changed up a gear, into second, putting the gearbox into manual.

Obviously I was flooring it and waiting for the gearbox to do its thing as the engine sat at the redline for a few seconds. Maybe 2 or 3, before I twigged what had happened and pulled a paddle.

Obviously the car and engine seems fine - just wanted other people's take on what failsafes the car has got built in? I'd assume it would be quite happy with redlining for a short period of time?

 

[Sustanon250]

I wouldn't worry about it at all , as long as you don't bounce off the redline in nuetral . Just don't do it on a regular basis .

 

[Toonshorty]

Most/all modern engines these days are fitted with a rev limiter which will stop you over-revving the engine, however on downshift this doesn't always work - after all you can't electronically limit the laws of physics. If I accelerate up to 100mph in a manual and then drop it into 1st, then I'll probably find myself looking for bits of engine down the A1. However, as far as I'm aware, the auto boxes will always ensure that it's safe to drop a gear before actually letting you - so if you keep clicking that downshift paddle, it won't let you go into a gear that would damage the engine. At least, that's always been my interpretation. However, that only applies to the auto - since the manual is purely mechanical, it is technically possible to do serious damage.

 

[AndyKnight]

That does not apply to the kick down. I dropped a few gears by the paddles the other day for an overtake and then accidently pushed the pedal too far so it kicked down as well which bounced me straight off the limiter.

 

[OliOC]

Thanks guys.

Indeed my car is an auto - from my understanding Toonshorty this is one of the reasons more and more high end cars (I'm not saying an M135 is high end here!) are available auto only.

From what I can gather if you floor it with the auto box in sports auto mode it redlines every gear change. It just doesn't hold the engine there for any amount of time.

 

[OliOC]

That does not apply to the kick down. I dropped a few gears by the paddles the other day for an overtake and then accidently pushed the pedal too far so it kicked down as well which bounced me straight off the limiter.

Funny you say that.

In my previous M135 I tried that a few times - throttle to kick down then pulled the down paddle, and yes the car will select the lowest possible gear, but I always found you essentially had to change up 1 gear immediately as it was at redline.

You would only really want to do this for an overtake, but I quickly realised you're better off pulling 3 or 4 downshifts and having control of where you are in terms of revs.

 

[pitbull666]

Doesn't pulling the left shift paddle for a few secs result in it rather then drop one gear it automatically drops to the lowest gear so in essence the same as kick down?

 

[nickfrog]

I didn't think it was possible to buzz an engine with an auto tranny.

 

[frazzle]

I'm sure its fine. Many of us will have done the same. It will have felt painful but the rev limiter is designed to ensure we can't break our cars.

 

[nickfrog]

How can the rev limiter do that on a downshift ? I thought the box was the fail safe by not letting a "buzzing gear" do its thing.

 

[Penetrator]

Probably will explode very soon

 

[OliOC]

Cool, I'll look forward to it ;-)

 

[br0wny]

Cars ****ed now you may aswell get rid

P.s it's fine

 

[OliOC]

Doesn't pulling the left shift paddle for a few secs result in it rather then drop one gear it automatically drops to the lowest gear so in essence the same as kick down?

When in manual mode, if you push the pedal to the kick down then pull a downshift the gearbox will change to the lowest possible gear. So if you're cruising along at 50 in 7th, in manual, floor it to the kick down then pull a downshift, the box will change to 2nd or 3rd.

The downside as I said above is you've got your foot to the floor, so maximum throttle, and not a great deal of revs left, so when I've tried it you tend to redline almost immediately unless you change up a gear.

 

[scrounger]

At least you'll have cleared all the crap out of it.

I wouldn't worry about it. As mentioned, that's why they have a limiter.

 

[AndyKnight]

Doesn't pulling the left shift paddle for a few secs result in it rather then drop one gear it automatically drops to the lowest gear so in essence the same as kick down?

When in manual mode, if you push the pedal to the kick down then pull a downshift the gearbox will change to the lowest possible gear. So if you're cruising along at 50 in 7th, in manual, floor it to the kick down then pull a downshift, the box will change to 2nd or 3rd.

The downside as I said above is you've got your foot to the floor, so maximum throttle, and not a great deal of revs left, so when I've tried it you tend to redline almost immediately unless you change up a gear.

I was doing it in the exact opposite order. I had changed to the gear I wanted and then kicked down by accident putting me right on the limiter :-(

 

[pitbull666]

It does state in the manual the auto won't allow you to drop into a lower gear which is not suited for engine and car speed!

 

[nickfrog]

I wouldn't worry about it. As mentioned, that's why they have a limiter.

Which is not going to prevent buzzing the engine on a downshift.

I still don't know if the ZF has a fail safe preventing such downshift in "manual" : I assume so. Does anyone know for sure ?

PS : just saw pitbulll has answered that one - not surprising. Cheers.

 

[pitbull666]

Taken from the manual phone app

http://s834.photobucket.com/user/pi...0B8E1B87-49E5-4152-B4E6-953EFE9EF597.png.html