Astra sports tourer off load rattle

[Mikey92]

Hi all, needing a bit help and advice here before i start pulling engine to bits,

I have a 2013 astra sports tourer 1.7 im sure its a a17dts, when driving then come of throttle whist car still moving the car starts making a rattle noise, give it some throttle its stops come off it again it starts again, now to me im hopping its a pulley or something but just wondering if anyone else has had issues like mine, I know the engine is quite loud anyway but this doesn’t sound natural 

[Vauxhall Owners Club]

Hi...welcome to the Forum

Its a tough one, but sometimes when a pulley is breaking up it will make an audible sound on overrun (due to centrifugal forces throwing out the components as they slow down).
So it could be a pulley, or a Dual Mass Flywheel, or a timing chain, big end bearings, etc

It would be best to take it into a good independent garage for them to diagnose the area that the sound is emanating from.
An easy way to eliminate the crankshaft pulley is to remove the auxiliary drivebelts and see if the noise disappears (when stationary off course)

Let us know what you find

[Mikey92]

Ill start by taking belt off and having a look for any odd moving pulleys and sound changes and  ill get back to you, I dont think its the flywheel as sound continues when clutch being depressed and pumped with no change in sound Ill get cracking on with it today

thanks for now

[Vauxhall Owners Club]

How did you get on with it Mikey92 ?

[Mikey92]

I removed the serpentine belt , checked for play in pulleys drove the car with no belt, and never heard any sound, however it never does it on que anyway, built car back up but sound has came back, after driving car for a bit the sound has returned and have noticed it quietens down when depressing the clutch, but dont want to say flywheel as when clutch is depressed its also taking the load off the engine. So still stuck at moment, I am tempted to jack front wheels off ground and secure it so I can drive it in place so i can pin point what it is

[Vauxhall Owners Club]

If it is making the noise with the belt on then it is the crankshaft pulley (harmonic balancer) that is breaking up.

You will need to replace the pulley with a later improved replacement one (probably dealer supplied) and usually a tensioner which will be of a different diameter possibly and also a new belt which should solve the issue.

 

[Mikey92]

Il see if i can source the parts and replace them and il get back to you hopefully by the weekend 

thanks for now

[Mikey92]

Is there anyway i can send you a video with the sound in it? To big to upload on this

[Vauxhall Owners Club]

To be fair it is always difficult to diagnose noises from video but how you describe it and also that with the belt off and it disappears then this does suggest the pulley being faulty.

Sometimes, if its recently had a cambelt then this can follow shortly afterwards

[Mikey92]

Hi again, removed the crank pulley today, removed 4x 12mm bolts , unfortunately no balancer just solid metal, check all pulleys and timing belt all fine, what i am wondering if it could be the o/s driveshaft , just by the sound of the problem and when and how it happens, so going to remove it tomorrow for inspection 

[Vauxhall Owners Club]

Well thats good news, onto the next suspect parts.

Let us know how you get on with it