Rattle clunking noise when revs drop to idle

**pugs,signum** · 29th September 2009, 22:29

Hi,

Im wordering if anyone can shed some light on an annoying sound i get when the car is ticking over and i give it a rev and let it settle to idle i get a rattling/clunking/knocking sound, iv had a look under the bonnet and had someone give it a rev and release to see if i can find the problem, if the clutch is fully pressed it makes the same sound also get same sound when starting the car in morning but this is only from time to time, its a signum 1.9 cdti (150) all runs fine except a slight jerk just after 2100 revs when cruising at those revs, i think this might be the third injector problem or a faulty temperature sensor that might be reading incorrect temperature resulting in an alteration of fuel to air mixture that in turn gives a slight jerk?

found this thread and will try this out as it wont even cost £2
http://www.vectra-c.com/forum/showth...exhaust+rattle

thanks in advance
pugs

**gav_embo** · 30th September 2009, 09:04

i have the same problem i think it sounds like the exhaust nocking in it brackets let me know if u find what it is

**pugs,signum** · 30th September 2009, 18:18

Originally Posted by gav_embo

i have the same problem i think it sounds like the exhaust nocking in it brackets let me know if u find what it is

What engine you got mate?
After doing a lot of reading on here lastnight, it pionts to the DMF (dual mass flywheel) hoping this is not the problem as it costs around £1000 to do, i paid more attention to the sound today while driving home from work and i found that the sound stops when clutch is fully pressed to the floor eventhough i said otherwise yesterday! its been doing this for over a year but only now wondering what it is

**plasma** · 30th September 2009, 18:34

Yep sounds like the DMF to me too. It will probably rattle a bit with your footing resting slightly on the clutch pedal and also on the rundown to idle

**gav_embo** · 1st October 2009, 00:25

1.9cdti 150 hope it not the dmf ive already had to do the inlet mani

**pugs,signum** · 1st October 2009, 18:06

Originally Posted by gav_embo

1.9cdti 150 hope it not the dmf ive already had to do the inlet mani

Same engine as mine and your not alone there mate i did my inlet manifold in january costing over £600

thought about getting rid of it but i looked on auto trader and be lucky to get £4500 but i owe £5500 still so think id be better off sorting the dmf out in the new year n splash out a grand at least that way i know iv got a car with new swirl valves (inlet manifold) and a new dual mass flywheel that should last me so i can keep it for many years and run it into the ground.

Or am i just

?

**gav_embo** · 2nd October 2009, 08:08

cost me 470 for manifold to be done as for the dmf that can wait a long long time to be done got to put 4 new tyres on it this week oh the joys ov motoring