RPMs rising while at a stand still

[kpamir]

Hello all

I picked up my 2015 fr-s over the weekend and have spent the last couple of days driving around as much as I possibly could in order to be prepped for my traffic jammed commute to work. This is my first manual transmission car.

On my way back home this evening I noticed something very weird.

While stopped in 1st gear in gridlock and with the clutch and break engaged, foot is completely off of the accelerator, and I notice my RPMs rising to around 2k or so and staying there.

This happened a few times throughout the gridlock portions of my commute.

If I put the car in neutral the RPMs would go down to do 1k or there abouts, but since I have the clutch fully down there really should be no difference right?

Any thoughts?

[pushrod]

I would give it some time before worrying about it.

Don't sit there with your foot on the clutch. Put it in neutral and take the clutch in whenever reasonably safe to so.

[civdaddy]

Originally Posted by pushrod

I would give it some time before worrying about it.

Don't sit there with your foot on the clutch. Put it in neutral and take the clutch in whenever reasonably safe to so.

Agreed

[chaoskaze]

Actually mind if I ask something on the side. when I drive I tend to have clutch in most of the time at stoplight & cruse in neutral. Is it a bad habbit that can lead into stuff prematurely breaking apart?

[zkv476]

The ecu knows when the clutch is and isn't depressed so it's doing some strange behavior. I've never heard of that before. Did it just start doing that or always did (or you just noticed)?

Originally Posted by chaoskaze

Actually mind if I ask something on the side. when I drive I tend to have clutch in most of the time at stoplight & cruse in neutral. Is it a bad habbit that can lead into stuff prematurely breaking apart?

When you keep the clutch depressed you are constantly loading the throw out bearing and shortening its lifespan. You are also stressing the pressure plate by keeping it loaded. There's debate as to whether these two issues are significant at all. Most say those parts will last longer than the clutch disc regardless, but why test that theory when leaving it out of gear and not pressing the clutch in is certain to be safe.

[Ultramaroon]

Originally Posted by chaoskaze

Actually mind if I ask something on the side. when I drive I tend to have clutch in most of the time at stoplight & cruse in neutral. Is it a bad habbit that can lead into stuff prematurely breaking apart?

If I'm first in line I usually leave it in gear and keep an eye out for sleepers in my rear view mirror. If I'm stuck in between people no sense in putting extra time on the throwout bearing.

Apparently it's illegal to coast in neutral. I don't understand why. Someone will educate us.

[Ultramaroon]

Originally Posted by kpamir

While stopped in 1st gear in gridlock and with the clutch and break engaged, foot is completely off of the accelerator, and I notice my RPMs rising to around 2k or so and staying there.

This isn't normal. I don't understand the wait-and-see approach here. Anyone care to elaborate?

[kpamir]

Originally Posted by zkv476

The ecu knows when the clutch is and isn't depressed so it's doing some strange behavior. I've never heard of that before. Did it just start doing that or always did (or you just noticed)?



When you keep the clutch depressed you are constantly loading the throw out bearing and shortening its lifespan. You are also stressing the pressure plate by keeping it loaded. There's debate as to whether these two issues are significant at all. Most say those parts will last longer than the clutch disc regardless, but why test that theory when leaving it out of gear and not pressing the clutch in is certain to be safe.

Ive been driving the car since Saturday (when I picked it up) and last night was the first time this happened. Ive been paying very close attention to the sounds the car has been making since they are a helpful cue for me when shifting gears.

Just to clarify, at stops what I have been doing is putting my left foot completely on the clutch (it is down to the floor), my right foot is also on the brake, and I have it in first. Doing that is damaging to the clutch?

On hills I end up releasing the clutch a bit untill it semi engages so I dont roll back when I release the brake and hit the throttle.

What you guys are recommending that when I am at a stop, i put into neutral let go of the clutch and have the brake held down correct?

Im gonna take it into the dealership this weekend to get it looked at.
I've been driving it a lot the past couple of days since getting it but I havent jacked up the RPMS past 4k

[jvincent]

I'd definitely take it in to the dealer ASAP since that isn't right.

When you start it the RPMs are higher for a couple of minutes but once you are warmed up it should stay at the idle setting (700 RPM).

[kpamir]

I will definitely give them a call and set something up.

I did notice this morning that when I started the car the it was idling at around 1500rpm for about 10 or so seconds before coming back down to about 700ish rpm. Like you said Jvincent.

On my commute to work I did not have any issues with the RPM rising when at a stand still. I was also making it a habit of shifting to neutral at stops instead of having my foot on the clutch

I am definitely gonna keep an eye on it regardless. I dont think I am doing anything truly damaging to the transmission, as this is my first manual car I have some issues here and there, and my take offs definitely need work, but I am not flogging the car by any means.

[FT86JC]

I use to have this problem in my last car, a 2003 mustang, it was the throttle positioning sensor that was messed up and kept my rpms constantly fluctuate at red lights.

[Ultramaroon]

Originally Posted by kpamir

Ive been driving the car since Saturday (when I picked it up) and last night was the first time this happened. Ive been paying very close attention to the sounds the car has been making since they are a helpful cue for me when shifting gears.

Good job on paying attention to sounds but don't worry too much. You'll kill yourself sweating every little hiccup.

One thing that hasn't been mentioned yet is the idle control while coasting. It's normal for the idle to get kicked up to 1000 RPM while coasting. It should relax to 650-700 when you stop rolling.

Originally Posted by kpamir

Just to clarify, at stops what I have been doing is putting my left foot completely on the clutch (it is down to the floor), my right foot is also on the brake, and I have it in first. Doing that is damaging to the clutch?

Not at all. No worries.

Originally Posted by kpamir

On hills I end up releasing the clutch a bit untill it semi engages so I dont roll back when I release the brake and hit the throttle.

Handling it like a boss. No shame in using the e-brake. That's why it's not just a pedal on the floor.

Originally Posted by kpamir

What you guys are recommending that when I am at a stop, i put into neutral let go of the clutch and have the brake held down correct?

It's a judgement call. Find your comfort level. Again, if you stay in gear you are prepared to make an evasive manoeuver but it can get old.

Originally Posted by kpamir

Im gonna take it into the dealership this weekend to get it looked at.
I've been driving it a lot the past couple of days since getting it but I havent jacked up the RPMS past 4k

Not the end of the world if you have an oops moment. There's a school of thought that the variable valve timing components also need to be exercised and that timing shift doesn't max out until about 5K.

[kpamir]

Yeah once the car has settled, it idles around 700ish rpm.

On that topic, I haven't had the RPM rise on its own since my commute home on Monday, don't want to speak too soon but hopefully that was just an isolated incident.

I actually find the e-brake hill start more nerve wracking than doing it with the clutch.

[pushrod]

Originally Posted by Ultramaroon

Apparently it's illegal to coast in neutral. I don't understand why. Someone will educate us.

It's illegal because if you're in neutral, you're not in control. The throttle doesn't do anything useful while in neutral, meaning that you can't use it to control the vehicle.

I put it in neutral under braking where the speed change is significant, but even then, I have my hand on the lever, ready to grab whichever gear is suited to the speed I've braked to so far. It's not even really "being in neutral" in this case, it's more like a prolonged downshift. If I make it to a complete stop, I leave it in neutral "for real", unless I know I'm about to take up again, or if there's no one stopped behind me and I need to be able to bail if I think I'm going to get rear-ended.