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Massive vibration can't find fault

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3.8K views 21 replies 9 participants last post by  dgmayhead  
#1 ·
Someone please help I'm out of ideas as to what is wrong with my car!well what 3 things are wrong :/ firstly occasionally when car is warm and I have been driving a while I get a loud squealing sound I think from the drivers rear tyre. I press the brake it's gone. It's persistent for about 30min then just stops for no reason garage can't find anything break pads and calliper all good had my camber tracking and balancing done still does it. Secondly when in 2nd and accelerating at about 3500rpm just before I change gear I a scraping sound from I think passenger side. Again garage can't find anything from anywhere. And finally the big one. Sometimes and I mean once a month maybe I'm going in the motorway and about 60mph I get a massive vibration the whole car shakes violently. So much so it damaged my upper suspension wishbone. Put the clutch in and decrease speed it stops I accelerate it starts. I get towed to a garage and boom it's all better in its own no faults can be found and when we take for test drive it's fine then few weeks later it happens again. The only thing I have noticed about all the times this has happened is that I have been in or recently been in the red for fuel and it's always on a slight hill or dip. Car feels more wobbly and really stiff when going over bumps generally but I don't know if that's the new suspension. Plus I have in the last 12 months has a clutch, flywheel, can belt thermostat and water pump. Any ideas I love my GT but I'm gonna have to get rid if I can't find the faults before it breaks my suspension again or worse damage
 
#3 ·
first issue is sticky brakes or caliper, if caliper is fine it might only need cleaning and copper greasing of the base the pads sit in,
second--need more detailed description coz scraping sound can refer to few issues
third issue is related to fuel system, i think your fuel tank and system needs cleaning out and the fuel filter might need changing assuming you have a diesel car
 
#6 ·
Your "massive vibration" issue seems like it would have something to do with the fuel system. Does the engine sound change during this vibration, or does it remain the same? If it changes, it's likely some issue in the fuel system. If not, I'd say a clutch system issue, though it would be weird that it would manifest itself so intermittently.

On the squealing, as others have said, the only thing it can realistically be is a sticky caliper. Get someone who knows what they are doing to strip and refit it properly. The only other thing it could be at the rear wheel would be some issue with the bearing, but I can't think of any way a bearing issue could produce a squealing sound.

The "scraping sound" issue needs more description.
 
#7 ·
Ok so fuel system problem I'm gonna drain my tank as that's what I thought it was water maybe. And the back wheel when its squeals I once stopped and threw water on the calliper and it stops so I wil get that checked cheers. And the scraping sound at the front sounds like something going round and round and catching but I only hear it at high rpm in 2nd gear and not all the time. More so when I'm going up a hill change gear and it goes away
 
#9 ·
Yes all cambers tracking and balancing done tyres are perfect. It's actually started vibrating again today. Listening to the engine it sounds louder and dirty even. It also feels like it's struggling as soon as I'm up to 50mph I put it in 4th and massive vibration if I ease off the accelerater or put the clutch in vibration stops pull the clutch out if I'm above 50mph and it starts shaking violently again
 
#12 ·
Squealing brakes, that starts after you've been driving a while, and goes away when you press the brake is most likely sticking rear pads - very common problem on these cars.

Can't really help with the "scraping noise", but may be worth checking that the brake backplates are not touching the discs; this can sometimes occur due to a build-up of rust on the inner face of the disc, and they can also easily get bent (when changing the clutch, for example).

As for the vibration, I'm going to assume that the car is a diesel, and suggest that you have a problem with your inner driveshaft joint - this is also a common problem. The reason it starts after you've been driving at higher speed for a while is because the joint gets hot and starts to seize.

Finally, as others have suggested, you need to find a competent mechanic who is more familiar with these cars - this will save you a lot of time and money.
 
#13 · (Edited)
I'm fairly sure (if your car is diesel) that your problem is a blocked/stuck EGR valve. As it sits at the rear and top of the engine (well it does on my 156 2.4 JTD) it's relatively easy to access. It should also show up on a diagnostics, but the cleaning and freeing of the valve would probably be cheaper than running the diagnostics. If you're reasonably handy with a spanner it is possible to DIY.

I had to perform a manual ECU reset to obtain the benefit of the valve cleaning, because the ECU was still running on the 'bad memories'.
 
#15 ·
I'm fairly sure (if your car is diesel) that your problem is a blocked/stuck EGR valve. As it sits at the rear and top of the engine it's relatively easy to access. It should also show up on a diagnostics, but the cleaning and freeing of the valve would probably be cheaper than running the diagnostics. If you're reasonably handy with a spanner it is possible to DIY.
Agree: blanking egr is a worthwhile thing to do but sticking egr will not cause "massive vibration". The original post is describing symptons of sticky rear calipers and warn driveshafts/inner cv joint.
 
#18 ·
Ok so it's deffo no my egr valve because I had the vibrations for a few weeks then my alarm came on whilst I was away for my egr I rang the RAC they blanked off my valve a week later I went to garage and got a new egr for free as the one I had was 7months old and stuck open I had the vibration before during and after the blanked valve. And btw i was only getting 28mpg with it blanked doing a steady 30mph where normally I get 45mpg so it cost me a ÂŁ15 to get to my holiday destination and ÂŁ30 to get home. Blanking is only advised if you get re-mapped at the same time
 
#21 ·
Some years ago, I had an Alfa veloce sprint as a company car. When I accelerated hard or went round corners, the car would shudder/vibrate as yours appears to. I was told to take it to our local "mechanic" who dealt with all our company vehicles. He diagnosed the shockers for some reason, and gave a price to my boss. I wasn't happy with this, so asked if I could take it to a main dealer. This was ok'd and I took it in. About 2 hours later, I had a phone call...Your car is ready sir for collection...Whaaaaat? "There was some muck in the fuel filter being moved around, which occasionally caused the problem, we have now cleaned it out and it is now driving fine again, and ready to collect"........Amazing how the silliest thing can cause such shuddering/vibration. I would check your fuel filter!!!!