KEVOZS8

Recently my engine is began to make a clicking noise when accelerating above 2500 rpm the mechanic said that this noise is from the Rods probably .does anyone had such a problem knowing that I replaced my S8 engine with code AHC to ABZ engine on 2007 because it was dead too due to oil pump failure (I replaced to ABZ because I couldn't find any engine with AHC Code) .
Is it normal that an engine will go out if I regulary change the oil and filter each 5000 km (5W-40) after 75000 Kms with regular service done (Oil change & Belt replacement etc...)
I am 99 % positive that's its not the lifters because in my last 5000 kms interval I added 2 kilos of engine oil 5w-40 .and there is no clicking noise when its cold .please advise what to do because I love this car and its is been 10 years that I have it .

Prospeeder

Timing chain tensioners is a possibility. They are common failures on 4.2s and make a very horrid rattle.

silverd2

ABZ engine is a 32v WITHOUT cam chain adjusters ("tensioners")...and failed cam adjusters only cause rattle at start up and, in advanced stages of failure, ONLY at very low rpms and warm idle.

So, look elsewhere for the problem:

Belt timing off, bad fuel, bad knock sensor, etc...

Read codes...it would also help if you could post a good recording (video) of the sound.

Cheers

KEVOZS8

Belt timing off, bad fuel, bad knock sensor, etc...

Read codes...it would also help if you could post a good recording (video) of the sound.

Cheers[/QUOTE]

My Timing Belt is done more then 68000 km. its time to de the service but I want to be sure if its the noise its coming from the Rods so no need to spend time and money and change the engine afterwards .
Does the timing belt do this type sounds I will upload the video .

Thank you

KEVOZS8

This is the video please Advise what's this sound.

pocketchange

Is this (noise) something that occurred all at once? pc

silverd2

Sounds just like a stuck (collapsed) hydraulic lifter.

Not being there to pinpoint the exact location of the noise, sometimes an exhaust leak very close to the head (manifold) can sound more like a loud click...rather than the usual downstream exhaust leak noise that usually sounds just like a louder exhaust.

A much more unlikely cause (esp in an Audi motor) can be a head gasket breached next to one cylinder allowing clicking exhaust noise...that should be easy to see and locate, though.

Cheers

KEVOZS8

I supposed that at the begining we have remove the valve covers and my mechanic said everything is normal so next he decided to remove the oil pan to see if there is small debris from the rods and he informed me that there were small pieces of metals.
My first question is this possible and my engine starts right away no oil light ,normal temperature (always run with g12 50/50 mixture)regular oil and filter change and the rods fail ?
My second question is there any difference between the internal of an ABZ vs AHC/AKH . My original was AHC (s8 32 valves) in 2007 i swapped it to ABZ due to oil pump fail in my original engine .
Please advise before spending a budget on a used engine purchase .

pocketchange

Seems like your mechanic found the problem. I've yet to see anything positive come after finding bits of whatever in a pan. I'd locate another engine or part out the car. pc

KEVOZS8

I can not find an S8 engine with 32 Valves (AHC/AKH) or even an S6+ Engine (AHK) So My question can I fit a 32 valves head on a 40 Valves Short Block Because 40 Valves engine are easier to find in my opinion Engine Code ( AQH AVP AYS). Please advise me if I can or give me an alternative because I love this car and I don't want to scrap it .