sounds to me like your antiroll bar if the car has one has come adrift or possibly your exhaust has or is about to snap or a engine mount is on its way out if it only happens when your accelerating hard that means the engine is tipped to its (excuse the wording of this)most tipped if you know what i mean if anything is worn it may rub on a drive shaft or somthing well now ive made myself sound like a twit im going to be quiet again
the section off the exhaust that comes off the downpipe IS about to snap i know that... unless it actually has, and the sudden stop was it hanging too low and hitting a raised bit of kurb (parked up the pavement at the time) thus snapping it... dont think its an engine mount as the engine does seem quite secure never really been sure about ARB's if i dont know how it works i generally dont touch it so it could be that ill have it on a ramp sometime next week...
Possibly the gearbox mount is knackered, allowing the engine to twist when you try to drive it? I couldn't select second when accellerating hard out of a junction turning right, problem went away when I binned the old knackered hydo mount and dropped in a solid one. Just a thought!
Sounds very similar to the problem i having with my car at the moment!! Was getting a slight knocking then...... Something seemed to pop or bang and now I get a grateing/rumbleing sort of sound coming from the front off-side (by the pedals) over around 3k when going striaght and worse when cornering left at any speed? Had it picked up by the rac just after it happened and the guy hadnt got a clue what it could be? I have checked and had a mechanic check the cv joints, wheel bearings, bushes and nothing appears to have gone? Its booked in to vw this week to have it looked at!!
well it matters not anymore, see my thread in vehicle chit chat in just a minute... let me know anyway if they figure it out...
I found out that its an engine mount gone Vw rekon it was a dodgey mount cos they have never done one on the mk4 20v turbo I asked if they thought it had been thrashed and they said no definatly not So im happy cos i thought it was a gearbox fault or something and its covered by warranty