Focus 1.6 petrol diagnosis of light grinding when coasting
Discussion
Hi all,not sure how to diagnose this, any pointers much appreciated.
It is a Focus manual 1.6 2009. It has developed a noise that you can hear when lifting off/coasting with clutch in or out. If the car is under power you cannot hear the noise (but maybe it is there you just cannot hear it over the engine noise).
Have checked for anything rubbing on the driveshafts and did find that the undertray that goes under the crank was touching the driveshaft secured that but noise still present.
Put the car in the air, currently has space save on and put it in gear and went from first to 2nd and there was a heavy vibration and the traction control was activating on the dash. Turned that off and still there was heavy vibration that felt awful. Only extra thing to mention is that during the test It was on the spacesaver spare as the tyre needs changing. Note that before the space saver was on the issue was apparent. Can only really describe it as a grinding noise from the front of the car. Changed the rear transmission mount as noticed a clonk in the last couple of weeks occasionally when reversing this was completed yesterday when the test mentioned was carried out.
Bit of a catch 22 situation as MOT is due next month not sure if worth spending out on it so maybe get MOT done as it stands and see if it passes to work out next stage? Clutch was done last year Valeo brand as the first cheapo one lasted 2 weeks. Car is not driven with much mechanical sympathy (son thinks he can abuse it and things like this dont happen). Keep saying he will kill it 😞 Mileage is 156000 so quite high.
Edit wonder if the test was flawed as supported the car on the inner part of the wishbone so the wheels were hanging down a bit maybe that was causing the vibration.
It is a Focus manual 1.6 2009. It has developed a noise that you can hear when lifting off/coasting with clutch in or out. If the car is under power you cannot hear the noise (but maybe it is there you just cannot hear it over the engine noise).
Have checked for anything rubbing on the driveshafts and did find that the undertray that goes under the crank was touching the driveshaft secured that but noise still present.
Put the car in the air, currently has space save on and put it in gear and went from first to 2nd and there was a heavy vibration and the traction control was activating on the dash. Turned that off and still there was heavy vibration that felt awful. Only extra thing to mention is that during the test It was on the spacesaver spare as the tyre needs changing. Note that before the space saver was on the issue was apparent. Can only really describe it as a grinding noise from the front of the car. Changed the rear transmission mount as noticed a clonk in the last couple of weeks occasionally when reversing this was completed yesterday when the test mentioned was carried out.
Bit of a catch 22 situation as MOT is due next month not sure if worth spending out on it so maybe get MOT done as it stands and see if it passes to work out next stage? Clutch was done last year Valeo brand as the first cheapo one lasted 2 weeks. Car is not driven with much mechanical sympathy (son thinks he can abuse it and things like this dont happen). Keep saying he will kill it 😞 Mileage is 156000 so quite high.
Edit wonder if the test was flawed as supported the car on the inner part of the wishbone so the wheels were hanging down a bit maybe that was causing the vibration.
scoobydo123 said:
Changed the rear transmission mount as noticed a clonk in the last couple of weeks occasionally.
Have the person who did that check for engine flex, and also for anything close to moving parts or showing witness marks.Given that it happens while coasting, can you reproduce it with the car pushed slowly on level ground? Can you reproduce it by jacking up any corner and turning the wheel?
It sounds like you lifted the car up with the suspension on full droop, so that isn't ideal and COULD be the source of the vibration.
If you have a grinding noise then something is touching something it shouldn't be touching obviously.
It could be a suspension joint worn letting something move in an arc it wouldn't normally.
It could be the dust guard on the brake bent & touching the disc as it rotates.
It could be a wheel bearing.
Ultimately the only way to diagnose is to look for things & rule them out, if you aren't the guy to do that, you need to get it to a garage that can, or as was said above take it for it's MOT early (up to 4 weeks will get you a 13 month MOT if it passes or a month to fix it, before it runs out if it doesn't) and get them to look for it.
If you have a grinding noise then something is touching something it shouldn't be touching obviously.
It could be a suspension joint worn letting something move in an arc it wouldn't normally.
It could be the dust guard on the brake bent & touching the disc as it rotates.
It could be a wheel bearing.
Ultimately the only way to diagnose is to look for things & rule them out, if you aren't the guy to do that, you need to get it to a garage that can, or as was said above take it for it's MOT early (up to 4 weeks will get you a 13 month MOT if it passes or a month to fix it, before it runs out if it doesn't) and get them to look for it.
ok thanks everyone. I will get it up in the air again supported near the end of the wishbones so the driveshafts are at a more normal angle and also put the original wheel back on so there is not a difference in rotating mass. Will also make sure there is a second set of axle stands as back up in case something nasty happens. Will report back any findings. I think if I take it for MOT and it fails then it is off the road from that point if I understand the legislation correctly.
scoobydo123 said:
I think if I take it for MOT and it fails then it is off the road from that point if I understand the legislation correctly.
Only if there are any 'dangerous' problems listed. Still worth it I'd say as you likely wouldn't want to be driving it anyway in that condition!scoobydo123 said:
I take it for MOT and it fails then it is off the road from that point if I understand the legislation correctly.
Failing an MOT test does not invalidate any previous MOT test result that has not expired.If the test identifies a problem that makes the car dangerous to drive then it will need to be taken off the road until it is fixed, but it was already dangerous and hence illegal to drive - you just didn't know it.
Basically, taking an MOT test does not leave you any worse off than you were previously, it just means you know a little more about the state of the car.
Thanks all. Got it up in the air again supported so that the driveshafts are in the normal position still cannot run it in gear with engine on without getting traction control light so even when disabled on the dashboard menu I think it is detecting the rear wheels are not moving and maybe that's why the engine jumps around and feels rough as it is inducing a misfire to reduce power?
Here is a video of me spinning the wheel in gear is this just the diff and normal can get less knock if really smooth rotating the wheel
https://drive.google.com/file/d/1gJ5NOWKM3tnuhImWr...
Here is a video of me spinning the wheel in gear is this just the diff and normal can get less knock if really smooth rotating the wheel
https://drive.google.com/file/d/1gJ5NOWKM3tnuhImWr...
scoobydo123 said:
Thanks all. Got it up in the air again supported so that the driveshafts are in the normal position still cannot run it in gear with engine on without getting traction control light so even when disabled on the dashboard menu I think it is detecting the rear wheels are not moving and maybe that's why the engine jumps around and feels rough as it is inducing a misfire to reduce power?
Here is a video of me spinning the wheel in gear is this just the diff and normal can get less knock if really smooth rotating the wheel
https://drive.google.com/file/d/1gJ5NOWKM3tnuhImWr...
Stop chasing faults that aren't faults, you are only confusing yourself more.Here is a video of me spinning the wheel in gear is this just the diff and normal can get less knock if really smooth rotating the wheel
https://drive.google.com/file/d/1gJ5NOWKM3tnuhImWr...
If the issue is when you are coasting, why are you trying to drive the wheels with the engine? You have found something that is being caused by you putting your car in a situation it isn't designed to be in and confusing you & is misguiding you, just turn the wheels by hand.
Again, you have found something else that you don't understand & it is confusing you. You say yourself that you can keep the noise down by turning the wheel smoothly, by turning it "un-smoothly" you are causing the backlash of the gearbox/diff to be repeatedly taken up in opposite directions with every rotation.
Does it make the noise get worse or better when turning & if so how?
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