Car revs too much when changing gear

messy tessy

I drive a Peugeot 207 and both yesterday and today I've noticed when I change gear the revs counter goes up to 4 despite not having touched the accelerator before changing gear. I haven't noticed this problem before yesterday.

Just wondering is this serious and should I get it checked out before driving again? I don't know much about cars but don't want to be making this situation worse. Has anyone experienced anything similar?

Its 2012 and diesel.

greasepalm

if revs stick it could be dangerous when in gear,get it checked for safety sake.

chicorytip

The problem is either clutch related or a vacuum leak.

YbFocus

Throttle position sensor possibly, does it idle ok?

beauf

Clutch?

This thread suggests alternator, but I don't understand that.

http://www.peugeotforums.com/forums/207-36/207-revs-fluctuating-i-think-18492/

mullingar

chicorytip wrote: »

The problem is either clutch related or a vacuum leak.

I really doubt on both.

Op states pedal not being touched, so clutch slippage out of the equation.

Vacuum? On a diesel? there is a vacuum generator pump, but used to assist the brakes and to power the turbo actuator.

beauf

mullingar wrote: »

...Op states pedal not being touched, so clutch slippage out of the equation....

Which pedal do you mean because I understood the OP meant the accelerator. He has to touch the clutch pedal when changing gear. Maybe I'm not following you though.

beauf

Could anything demand more electrical power when he changes gear? or put more load on the alternator when not in gear.

YbFocus

beauf wrote: »

Could anything demand more electrical power when he changes gear? or put more load on the alternator when not in gear.

Not for 4k revving.

It can't be the clutch, it has nothing to do with the revs of the car.

messy tessy

I don't think it is related to the clutch - when dropping down gears I don't get this problem. It seems fine to me when idle also. I just wanted some indication prior to going to the garage with it. And to have an idea of cost of repair.

Thanks for all the suggestions!

YbFocus

Are you coming off the throttle completely before clutching?
Just something you may not notice yourself doing.

beauf

Ok its not always when changing gear then. So not the clutch.

YbFocus wrote: »

Not for 4k revving.

It can't be the clutch, it has nothing to do with the revs of the car.

Not with you. A slipping clutch lets the revs rise no?

YbFocus

beauf wrote: »

Not with you. A slipping clutch lets the revs rise no?

It will of course, but the OP says before touching the accelerator.
He/She will need to throttle up before it could slip.

messy tessy

YbFocus wrote: »

Are you coming off the throttle completely before clutching?
Just something you may not notice yourself doing.

I thought this myself when it first started happening and made myself put my foot on the ground prior to even touching the clutch when changing up gears - it didn't have any impact.

YbFocus

messy tessy wrote: »

I thought this myself when it first started happening and made myself put my foot on the ground prior to even touching the clutch when changing up gears - it didn't have any impact.

Does the car slow properly when you come off the throttle? Or is it holding it's speed/Accelerating?

Strange thing to happen!

messy tessy

YbFocus wrote: »

Does the car slow properly when you come off the throttle? Or is it holding it's speed/Accelerating?

Strange thing to happen!

I checked this also, it holds the speed for a bit before slowing. But it does slow down.

Other question was do you reckon its safe to drive home (2.5 hours) before getting it seen to?

YbFocus

messy tessy wrote: »

I checked this also, it holds the speed for a bit before slowing. But it does slow down.

Other question was do you reckon its safe to drive home (2.5 hours) before getting it seen to?

I think myself it's a dodgy Throttle Position Sensor misreading where your foot is.
I'm really not sure on driving it home, I would think it's ok for now but if it was to get any worse to definitely stop and get it checked asap.

Interslice

I'd say it's either injecting too much diesel because of a sensor gone or burning oil for one reason or another. Do you have an engine light on? Maybe a problem with the accelerator getting stuck or just going dodgy. I'd get it to a decent garage anyway.

beauf

YbFocus wrote: »

It will of course, but the OP says before touching the accelerator.
He/She will need to throttle up before it could slip.

I would have thought a slipping clutch would slip regardless of using the accelerator.

beauf

messy tessy wrote: »

I don't think it is related to the clutch - when dropping down gears I don't get this problem. It seems fine to me when idle also. I just wanted some indication prior to going to the garage with it. And to have an idea of cost of repair.

Thanks for all the suggestions!

So it only does it on accelerating?

Seems fueling related? Something electronic, sensor or fuel rated?

Let us know what it is when you find out anyway.

YbFocus

beauf wrote: »

I would have thought a slipping clutch would slip regardless of using the accelerator.

No you need to apply torque for it to slip, a car can idle around and be driven gently for quite a while before it finally gives in.
You will first start to notice a slipping clutch during full load situations and as the clutch gets near the end of its life the need for throttle will get less and less to the point it won't even move.

beauf

Sorry for being pedantic. I'm trying to understand this. An Engine running with no foot on the gas has torque even at idle no? Many diesels will pull of from stopped without using the accelerator, just put it in gear and it will move forward. With a slipping clutch it will just do, this later. All with no foot on the gas.

A smaller engine especially petrol doesn't have the the torgue to do this, so you'd only notice the clutch slipping on accelerating. But even with a small petrol engine, if you were engine braking (granted minimal effect) you'd have no foot on the gas and the clutch will still slip.

Sorry for dragging this slightly off topic.

beauf

What is surging?

YbFocus

beauf wrote: »

Sorry for being pedantic. I'm trying to understand this. An Engine running with no foot on the gas has torque even at idle no? Many diesels will pull of from stopped without using the accelerator, just put it in gear and it will move forward. With a slipping clutch it will just do, this later. All with no foot on the gas.

A smaller engine especially petrol doesn't have the the torgue to do this, so you'd only notice the clutch slipping on accelerating. But even with a small petrol engine, if you were engine braking (granted minimal effect) you'd have no foot on the gas and the clutch will still slip.

Sorry for dragging this slightly off topic.

Not pedantic at all Beauf

The torque within an idling engine (be it petrol or diesel) will not be fit to overcome the beginnings of a slipping clutch, it will towards the end get to a point where it will and the car will simply sit there doing nothing.

But at the beginning, as the clutch first begins to slip (it can take many months to finally give in depending on the driver and his/her ability to nurse it) it needs to be under full load.

For example in your top gear, already doing 100kmh and now you go full throttle. Your loading the engine completely and also adding the hardest gear to accelerate in and also there is a drag factor to take into account.
This here is a situation where the clutch is under max load.

This is where you will see the first tell tale signs of a slipping clutch, not on take off as it really isn't under massive loads unless you are burning off from traffic lights or whatever.

From takeoff you are in the nicest gear to move in (think of the ease of cycling in the lowest gear on a bike compared to the highest) and you won't be anywhere near full throttle, there's little to no drag to consider either so your clutch will be happy

corktina

It sounds to me like badly described clutch slipping.

arthur daly

Well it's not the clutch,the clutch and accelerator are different units.
If the car is reving when the clutch is pressed down it is a accelerator problem so something is sticking where it shouldn't or a sensor.

If it's a clutch problem the car will rev higher in gear while driving.

I would be inclined to wd40 any moving parts both at peddle and at engine first then maybe start looking at sensors.

beauf

Floor mat? - I have no idea. When you look up the 207 forums theres so many different reason for things for revs rising. I'm as curious as heck now though.

messy tessy

My own thoughts were that it can't be the clutch - as only happens when increasing through gears...but as I said I don't know a huge amount about cars.

Spoke to the garage guy so will bring it in next time I'm home. When undoubtedly it will work perfectly and make me look like a raving lunatic! Will let you know.
Thanks again

pippip

If it is the clutch wearing, and slipping, then you should be able to test it by putting it into a higher gear than needed and putting your foot down. If the revs go up but your speed doesn't then its the clutch.

Row

Get it plugged into some decent diagnostic equipment and get them to check the accelerator position when this is happening....don't go spraying wd 40 on the pedal as these units are "drive by wire" and are totally electronic not like the older "cable" accelerator pedals.
Post your location and maybe someone on here maybe able to help out.