Loud knocking only at idle

[Damian stewart]

Hi all I went for a drive today in my ba XR6 t and put the foot down it stuttered and backfired now when. Its at idle its making a bad rattling/tapping sound but when you rev it the sound goes but as soon as it idles it starts again and  nearly stalls and doesn't want to run but weirdly enough when you rev it it's like nothing's wrong at all please help I may also add it needs vct solenoid as it's over advancing so that could be why it want to stall but really hope it's nothing major could it be a lifter or soft valve spring

Can upload a video of that helps

Edited 26/05/19 12:40 AM by Damian stewart

[k31th]

just replace the VCT solenoid and see if it helps.

[Damian stewart]

The vct wouldn't cause this rattling tapping noise at idle would it ?? It sounds like something broken but the weird thing is when you rev it the sound goes away and seems fine whilst keeping revs higher then 1500rpm

[k31th]

it's hard to know what you mean by a rattling/tapping noise if it doesn't get worse when you rev it... could just be a loose exhaust item or heat shield which moves into a "not loose" sort of place when the engine flexes as you rev it.

[Damian stewart]

Definitely not exhaust rattling seems to me like something at the top end of the engine 

[k31th]

you can use a long screwdriver as a sort of crude stethoscope to help pinpoint which part of the engine is emanating the sound you speak of.

[Damian stewart]

Ever since the sound has started today it doesn't want to rev sometimes then comes good and revs it's got me stumped

[cookie monster]

Hey I see it's been a few years. But I'm going through the exact same thing what did it end up being

[Markus1986]

Any updates chaps? 
This sounds like what’s happening to be FG F6.

my car returned from the mechanic after having a new timing chain,guides, tensioner and idle pulley.

The noise comes and goes and only seems to be at idle car runs great and the noise rarely presents itself.