UPDATE: VIDEO! VW Golf 1.4 aex knocking sound, can you offer me some advice?

[AlexMozza]

The problem is that if it the bearings then there is no real way to tell, bar the sounds, and as wayne said, they will eventually go, and that would  be a complete rebuild :/

Only way to find out for sure it to look :/

[Leon27]

Have you determined where it is coming from? i.e:

Rocker cover
Head
Upper block
Lower block
Sump
Tensioner/Rollers
Pumps

Get a long screwdriver and put the tip on each component above and place your ear on the handle. Wherever the sound is louder you'll know what area to target.

As said by everyone - you cannot be sure until you have a look and ideally you don't want to drive it incase matters are made worse.

Don't stress just yet dude - until you know what you are dealing with there is no point. Been there with my Mk2 tappets, one sounded like it was hitting the rocker cover.

[01664gti]

Can you make a video of it??It may help us to help you a bit more.Many of us have been around these engines for years so you never know

[Rmachines]

Hi, your engine is a short block A series engine,   Its piston slap!  Its when the piston rocks from side to side slightly on the up and down strokes.  Its pretty normal to be honnest, all the later 16v engines in the polo and MK4 golf also do it.

My Old 1.4 did it badly, very heavy knocking under load, Worse when cold,  Almost totally goes away when decelerating, Sound about right?

Anyway before i did my engine swap for a 16v gti engine i ragged the living crap out of my 1.4, i had it on the limiter for 10 mins at a time, After taking it out and stripping it down there was only very slight ovaling of the bores and the pistons looked fine, so its nothing to worry about.

Its almost certainly piston number 3, The only cure is a new piston,  and the only time to start woryying is if its a clackety banging noise and missfiring or a loud clicking noise/burning oil badly.   Any to be honnest it would take a lot of hard abuse to get it to that point.

I recomend living with it, and keep up regular oil changes as per service schedule.

Hope that helps a bit. 

[joehb10]

Rmachines, your spot on with the part about not knocking on deceleration. Thank you rmachines for that reply, by the way, ive taken a video with audio of the engine today. The engine was run for about 40 mins while driving home so this is the normal idling sound really of the car...thanks

check out video link below...! What you think...

http://www.youtube.com/watch?v=FA0e-Eeh9bs

[01664gti]

sounds like top end to me

[Rmachines]

Yea, it sounds a bit top end ish in the video there but its deffo the typical AEX piston slap there,  and that's not a bad case of it by any means

http://www.youtube.com/watch?v=-_bOFOy-3Ic&feature=related

I know that vid is a different engine but that is the typical piston slap noise, and even when that loud its still not going to suddenly fail   Its less chattery and more of a knock if its just the one piston like in your case.

[Wayne]

I think your mad to keep running it sounding that bad.

[Rmachines]

Since working for honda i must have serviced 10  accords with the F20Z1 engine and some of those have just sounded awful!   Honda dealer technical say "Its due to the manufacturing process and does not require attention"   And that's coming from honda!  Never heard of one failing, doubt any of the master techs have either.

Anyway, same case with the golfs.   Mine did it,  my brothers 1.4 16v does it  several i have appraised at work have done it,   and i hear polos and other golfs regularly with heavy piston slap (all AEX AEE and AE series blocks)  None of those are going to blow up any time soon.   Mine did 40k miles and never got any worse, and after stripping it down, there was only very slight play,  More than anything its down to the design of the block making it louder than what it really is.  So unless its burning oil or misfiring it aint worth forking out for.   And 90% chance a 2nd hand engine will sound exactly the same!   Just keep up services and watch for lack of power/slight misfire and heavy oil usage.

[AudiA8Quattro]

Out of interest, have you had the oil pressure checked?