Vibration At 3500Rpm

[ALake]

I've noticed a bit of extra engine noise and some vibration that can be felt through the seat, at 3500 rpm but independent of road speed. So it seems to be engine or exhaust related. It would be at about 60mph in fourth, 75-80 in fifth etc.

I know petrol engines can have a spot where they can become boomy, but the vibration I can feel (through my backside basically!) suggests something else. I don't get any wheel wobble either. Is the exhaust mounted underneath the drivers seat by any chance?

[igormus]

I've noticed a bit of extra engine noise and some vibration that can be felt through the seat, at 3500 rpm but independent of road speed. So it seems to be engine or exhaust related. It would be at about 60mph in fourth, 75-80 in fifth etc.

I know petrol engines can have a spot where they can become boomy, but the vibration I can feel (through my backside basically!) suggests something else. I don't get any wheel wobble either. Is the exhaust mounted underneath the drivers seat by any chance?

have you inspected MAF sensor ? what is an air filter condition (enginie's)?

whether you feel it when driven up-hill?

[ALake]

Filter looks new but I haven't looked at anything else (still has some warranty left!)

It doesn't make any difference uphill, downhill or road surface it just comes in right at that rpm and disappears within a few rpm up or down of that!

[igormus]

Filter looks new but I haven't looked at anything else (still has some warranty left!)

It doesn't make any difference uphill, downhill or road surface it just comes in right at that rpm and disappears within a few rpm up or down of that!

it looks like possible contra pressure on an exhaust or sparks (???) no offends matey - but whether you shift gears at correct speed giving no overloading to the engine? I can not see other reasons now. Check with MAF condition -- may be a lack of an air is a simple reason.

[ALake]

I tend to change up early if anything. You can feel it even under gentle acceleration, when on the motorway and gradually building up speed to where it hits that rev point. It's not worse or better under genteel or hard acceleration really!

[igormus]

I tend to change up early if anything. You can feel it even under gentle acceleration, when on the motorway and gradually building up speed to where it hits that rev point. It's not worse or better under genteel or hard acceleration really!

what about co-ordination of gas pedal with throttle service motor ? may be motor gets late signal to accelerate engine even though you ve changed gears in time

regards/Igor

[ALake]

I don't think its the way I drive - it comes in at 3500rpm when I'm in fifth on the motorway so no clutch action involved at that point.

[DjRav]

If it does it whilst stationary that will rule out wheels drive/prop shafts and transmission etc.

Still leaves a whole lot more though!

Clueless Dave

[anchorman]

I know what igormas is getting at. If there is the beginnings of a misfire it will come through as a vibration. Have you noticed any fall off in fuel consumption?

It could be a vibration dampener on the crank pulley so worth a check there. Don't let your brain run away with it though!!!

[ALake]

Fuel consumption seem steady at the 30-32mpg average over my commute.

Never even thought of crankpulleys etc,Now I'm worried! With it having some warranty left on it I suppose I'd better get it booked in!

I was hoping my rav was going to be a paragon of toyota build quality and reliability, the avensis I had a few years ago certainly wasn't!

[bigend]

Yeah the pully damper issue happened on my punto jtd about the 150,000 ml new one cut a lot of noise and vibration out, the worse thing is because these things happen over a period of time you tend not to notice

Keith

[anchorman]

There might be nothing wrong but just get it looked at to check.

[ALake]

I've been out so I had a chance to check. With the car stationary it seems to be ok at 3500 (albeit noisy!) so it seems to be only when moving.

I assume the propshaft is turning all the time,even if the 4wd isn't engaged?

[anchorman]

Yes.

[ALake]

Could be propshaft bearings then, as I can feel it through the seat?

[anchorman]

There are UJs at the front, middle and back. There is also a centre bearing with rubber cushion. It is easy to check.

[ALake]

I'm guessing centre one, I'll have a look when the weather is drier! If I see anything untoward it's back to the garage.

[Big Kev]

That was my first unpublished guess, Alake for which apologies.........suspect transfer box gearing or bearings/ UJ.......

[ALake]

Well I foolishly thought a toyota warranty was worth the paper it was written on, but it seems not. The selling dealership want to charge me £80 or so just to look at it before they can say whether its covered by their 'comprehensive' warranty.

What a crock - thats put me off straight away. So much for customer service.

Never had this issue with the 3 Fords I have had with Ford approved used warranty -booked in, job done under warranty , no bother. Even when one was a wheel bearing which technically wear and tear they covered it out of goodwill 6 months into the warranty!

[Davrav]

Just tell them you expect the investigation charge to be waived should the issue indeed be covered by the warranty.

[ALake]

Tried that - no go. Needless to say they won't be getting any repeat business from me. They will waive the fee IF the issue is covered by the warranty, but I still have to pay it upfront. Sad misguided fool that I am I thought the toyota approved used warranty was solid gold and designed to give the buyer confidence in a used car.

I'll take it to an independent, if its a serious fault its getting p'xed straight away for something else. I had all this rubbish with an avensis years back and I put that down to just bad luck or a friday car!

[Davrav]

Frustrating but say the dealer sets aside an hour or so of workshop time to investigate what may or may not be the cause of a vibration based on what you have told them. In the event that no fault found or not covered by warranty, do you expect that investigation for free?

The warranty covers remedial work, not investigation.............

[ALake]

Like I said though, I've not experienced this in the past. Normally the dealer has checked, fixed the fault (or in the case of my old Vectra gave me a quote as it was stone damage to a condensor)

I went to toyota to avoid these sort of cowboy tactics, sounds too much like a chance to grab £80 for 'diagnostics' while I have to wait for the warranty to be decided. I have little faith in Mr T's warranty if the dealers are told to charge just to have a look.

[ALake]

Well to update this, one dealer agreed to look at the car for free. In one day and out with a new engine mount but no difference. So back in again and now they can't find anything wrong!

It's obvious to me that the vibration and noise that comes at a very specific rev range is not normal, it comes and goes at such a precise point regardless of road speed,surface or gear that it must be engine,driveshaft or exhaust related. Engine mount seem unlikely to me as I've had one go before at a much higher mileage and it resulted in knocking on corners.

This all reminds me of my old avensis which spent 35 days of my ownership in the dealer, seems that main dealers are stuck if they can't plug a laptop in and get an instant answer!

So my next job is to have a good look around myself and see if there's any loose exhaust mounts, etc. I never bothered with manufacturer warranties in the past as they have a vested interest in not pulling out money on your car and I won't bother with one again!

I did think of the propshaft, but if there was wear in there would not make a noise all the time, increasing with road speed? I can hear some drivetrain whine at lower speeds but I put that down to the engine being pretty quiet at that speed. My previous kia sportage had less whine but that could also be down to the noisier diesel masking it!

[gjnorthall]

Vibration through the floor of a car is often caused by the rear wheels being out of balance. I know that this doesn't entirely align with the observations but it may be worthwhile getting the wheels balanced for the modest cost involved. Presumably the prop-shaft UJ's and support bearing have been checked and that all the exhaust mountings are in good condition. I'm not suggesting that these items may be the sole cause of the vibration but quite small deficiencies can often be the cause of setting up a harmonic which is then magnified by another issue.