[philll]

Hi all

So the other day I was driving home and some guy behind was being....... "one of those".... so at the appropriate time, I floored it and I noticed after releasing the pedal the RPMs dropped from the sort of 7-9k whatever it is down to 4k and remained there even though I was now driving normally. It hasn't done it since... but has made me wonder why that occured and I haven't gone to those kind of speeds since as bit concerned what that was... it hasn't done that before.

Any thoughts?

 

[i860]

9k rpm? what motorbike are you driving?
1 minute stuck at 4k rpm?
jokes aside, you need a new acceleration pedal maybe.

 

[efair]

Just the gauge was stuck at 4k, even when actual rpms were much lower? That sounds llike a problem with the gauge.

Check your battery first.

 

[philll]

Just the gauge was stuck at 4k, even when actual rpms were much lower? That sounds llike a problem with the gauge.

Check your battery first.

Sorry I should have mentioned that the engine was truly reving at that 4k speed it wasn't just the gauge. But, it was like the car was in neutral as the car wasn't actualy trying to "drive" it was just coasting (as if you lifted the pedal up). Engine was roaring like it would at 4k and it maintained doing that for about a minute. Somewhere in the regions of 30-60seconds. Yet all Iw as doing was coasting along, no pedals pressed, engine roaring and showing 4k on guage. It was very weird....

 

[VAslk]

I've noticed the same thing on my '07 280 but never concerned. I don't however, remember it lasting much more than 5 or so seconds after I lift my foot from a period of flat-out acceleration. I always assumed the transmission was programmed that way to try to hit a matching RPM for the downshift. Kinda fun, though.

 

[efair]

So the situation was that immediately after some spirited driving, suddenly the transmission was in neutral and the engine was at 4K RPM, even though the shifter was at position D and your foot was off the accelerator?

 

[VAslk]

Trans had never moved but the car just still wanted to go for a brief time after I lifted the pedal. I never tried braking but I had no concern that it the inertia would jeopardize the travel. Continued high revs was such a short time anyway. I doubt I ever reached rev limiter speed anyway. Probably no more than a quick burst near 4 or 5K.

 

[philll]

@efair As @VAslk described it. The transmission never changed gears but the car revs were still high (4k or so) even though I was not pressing the pedal and was just coasting. It was LIKE it was in neutral and you were holding the pedal down ...except it wasn't and I wasn't lol. Maybe it's just how the transmission is programmed? It's a bit weird that it's only done this once but I don't know... thought it was odd is all.

 

[VAslk]

My impression, precisely. It was like the trans was programmed to stay there expecting you might return to the high K's after a pause for a perceived hazard (or momentary second thoughts). Certainly never a moment's concern that the engine was running away on me.

 

[Alex 3]

9k rpm? what motorbike are you driving?
1 minute stuck at 4k rpm?
jokes aside, you need a new acceleration pedal maybe.

I was thinking what gear was he in? Did he inadvertently downshift in which case it would hold the lower gear Ipso facto higher rpm.

 

[Berapotter]

You hadn't tapped the steering wheel buttons and limited into a max low gear had you?
I've done that a couple of times with those flappy things, pulled away and found it won't change up because fat-fingers has caught them. feel a right twit I do 💩

 

[LeonardoDaBenz]

If he had red lined it (7000 he says???) his dash would have lit up like a Christmas tree . He'd know it

 

[Alex 3]

If he had red lined it (7000 he says???) his dash would have lit up like a Christmas tree . He'd know it

I chuckled at the 9K! 🤣

 

[LeonardoDaBenz]

I chuckled at the 9K! 🤣

He did say "sort of ... whatever" but for a 280

but for a '55 :

 

[LeonardoDaBenz]

But we digress: why did it not reduce? I think the shifter must have been in manual mode and he just didn't realize it.

Has it happened since @philll or have you tried to replicate it?

 

[Berapotter]

I said that👍

 

[LeonardoDaBenz]

Great minds think alike 😁

 

[Avel Du]

I said that👍

You after Jeff's job?
Nobody listens to him either.
Especially his fellow admins.

Happened to Deb a while back. Sounded like a Scouse docker (Car and Deb).

 

[VAslk]

Gentlemen, I'm pretty sure I'd know if my shift lever was in neutral. Especially so if I had just passed some slow dolt on a busy highway. Enough of the "operator error" chat. I would agree to tech problems if the hesitation dropping revs after full throttle lasted more than a few seconds; mine never has. I just consider it to be some (probably-retired-now) engineer's whoopee cushion for us. As long as it isn't a surprise at a bad time.

 

[Avel Du]

TBH it is usually the other way around. ie at 4000rpm and goes to 7000rpm.

throttle pedal sensor can throw the odd wobbly.
Typical causes are wear, poor earth and water ingress along the wiring somewhere.

All of which can be intermittent. From the 'oh, that happened last year' to the 'oh no, not again' depending on severity.

@VAslk although you have had same problem, we do not know if the OP is as aware and it is their thread.