Weird issue: Revving a bit higher when engaging the clutch

[Kreindler]

Guys! So I have 2 more issues with the car, and one I wanna address here.

M54b30 with a manual 5 speed tranny (getrag).

I noticed a weird behavior today and I tracked it down and could reproduce it. Sometimes I felt and saw how the engine was revving a little higher (+200-300 rpm) when i was up-shifting immediately after I engaged the clutch to change gears..

At first I just thought maybe I have a bad moment and that maybe timing between engaging the clutch and getting the foot off the gas is a little off. So it just happened again now while I was driving home so I tested it: car rolling in second gear-> foot off the accell-> immediately engaging the clutch afterwards without any touch to the accelleration pedal- the engine was revving up a bit (2-300rpm).

Some other background info:
No the carpet does not somehow press on the accelleration pedal
When I did the last engine swap- the guy who did it told me my clutch is a little “used” and I should consider replacing it. But didn’t bother as it is still engaging and switching without any issue.

Now I don’t see how this could be related to the clutch being “worn off”.. with a worn off clutch- it doesn’t make any issues when disengaging - at least not in my experience, and I cannot think of a logical explanation.

Any idea?


Sent from my iPhone using Tapatalk

[Twistytee]

Check your clutch switch. Common condition for the rpms to surge when the switch begins to fail. Will also impact cruise control.

[jclausen]

Or your clutch up is starting to slip while in 5th gear try to accelerate if the rpms go up the car does not move forward very well your clutch is worn out

[BimmerBreaker]

Had an E36 do that to me before the clutch slave failed and almost left me stranded in oncoming traffic

[Kreindler]

Thx for the reply guys, i will check clutch slave and clutch switch. But still what I don’t understand from a logical perspective: how can the clutch cause this (as it is disengaging gear)?

In another car I had a really worn out clutch, and some problems with the clutch slave and behavior was totally different-> after I burned the clutch (don’t ask, stupid me)- it had problems with the second gear when i was doing a straight line launch, and the slave cylinder- it was leaking on the pedal.


Sent from my iPhone using Tapatalk

[Xavier1072]

Not trying to call you out here....but for clarity's sake, if you have hydraulic fluid leaking onto your clutch pedal? That's the clutch "master" cylinder, not "Slave".

Thx for the reply guys, i will check clutch slave and clutch switch. But still what I don’t understand from a logical perspective: how can the clutch cause this (as it is disengaging gear)?

In another car I had a really worn out clutch, and some problems with the clutch slave and behavior was totally different-> after I burned the clutch (don’t ask, stupid me)- it had problems with the second gear when i was doing a straight line launch, and the slave cylinder- it was leaking on the pedal.


Sent from my iPhone using Tapatalk