Shabbeh

Well, I would like to enlighten you guys on some history on my car. I live in Singapore so the driver seat is on the right side and mileage is calculated in KM. I drive an 04 Audi A8L 3.0L V6, right driver seat, mileage ~140,000KM (86,600MILES). I am not really a car expert...

Back around in April I allowed my friend to drive my car and he pretty much caused a gearbox failure, in which I cannot start the engine at all (I think he probably shifted the Gearstick into the "P" position before the car fully stopped but he still denies this till today), anyway the gearbox was replaced at the local workshop (which costed a bomb) and shortly after my engine suffered from some overheating issues, (making alot of noise) and upon inspection, it appeared that the fluid had escaped and the cap of the coolant bottle was loose (so probably my engine had suffered some damage as of that).

Anyhow after fixing all these problems and the damage that my car has gone through, a small problem has emerged, in that the car jerks whenever
1. I press the accelerator hard
2. When the car is moving around ~20KM/H (12MILES/H) and I move the Gearstick to the "N" position
so far I have avoided doing these 2 things so as not to exert any more stress on my car.

Additional things that I have noticed :
- When I accelerate from 0km/h, I have to lightly step on the accelerator initially. As the car speeds up, only then can I slowly increase the strength that I step on the accelerator, so as to avoid any jerking of the car
- So basically the car jerks when there it experiences a large ACCELERATION of speed
- I can still reach high speeds on the highway without any problems with the car jerking. So far the fastest I have dared to go is 140KM/H (86MILES/H)
- When the car is stationary, the car does not jerk when I move the gear stick to the "N" position while the engine is on. Apparently it only jerks when the car is moving, and I push the gearstick to the "N" position.

I am deeply grateful of anyone who might have any advice, or have previously experienced a similar problem and got it fixed by replacing a particular part or two. I am only willing to spend up to 2,000 as I am looking to get a new car next year or the year after. I am also aware of being able to purchase parts from ebay or have them repaired/remanufactured. So these are options that I am looking for if anyone could shed some light on the part that needs to be replaced!!!
Thanks so much in advance and thank you for reading my lengthy post , I just wanted to be precise so that you can understand my situation fully.

Regards,
Shawn Ng.

Midwestuser1

Check your coils as there's a thread in the D2 a8 area where a user had similar symptoms to yours and it was the coils in his case.

Midwestuser1

Read through the thread started by "Adjuster" titled "fuel pump blues". As you will see he determined it was the coils.

Shabbeh

damn, so hard to understand it! so many foreign words.
ahhh, trying to figure out from that post which piece did he replace then the problems went away. o_O

mishar

Welcome.

Car should be VCDS (VAS) scanned. If it is only under high acceleration it could be misfiring, caused by faulty coils or simply bad spark plugs. Scan will detect that.

Part with shifting to N is even less clear. Why would you shift to N while going ~20 km/h at first place?

Edd W

I suspect your car will have the same engine as many of the 3.0 V6 A6's -= there were no 3.0 v6 A8's sold in the US so there is not that much experience of that engine here in the A8 D3 forum.

As others have suggested, I would say most likely fault is spark plugs folled by ignition coils. Each plug has its own coild so a misfire will only due to a coil fault will only effect that plug. The faults should logged and these should be read using an ODBC scanner such as VAG-COM - if you do not access to this then you need to use a mechanic with VAG experience who has the correct equipment - I would suggest a different mechanic than the one who fitted your gearbox - if he returned it to you with faults it is not good sign!

Shabbeh

Ahhh, maybe I was not clear enough. When reaching a red light I tend to push the gear to N to let it drift, even though I'm too scared to try it now since the car staggers when I push the gear to N at low speeds I like how the car drifts at high speed on N gear.

Anyhow back to the main problem, so what I get from u guys is see the VAGCOM scan and see the corresponding faults and replace the parts?

(on a side note I had an earlier issue with my ABS system which the mechanic quoted a 4k repair bill, and found out later you can buy remanufactured/repaired for ~100USD or ~400-500 for a new one) So I guess there's a cheaper way to fix my car...

Shabbeh

Because I'm not a car expert at all, but I have done a little extra reading on the net mainly to fix that ABS problem, now I'm basically looking to fix the hard acceleration issue!!! My dad is just tasking me to fix up the car in exchange for more drive time with the car hahaha.

So basically you guys are suggesting to replace the ignition coils? Ok, I will look at the error codes at the mechanic soon!

Once again thanks everyone who has given advice on the subject. I am deeply grateful!!! :>

Shabbeh

Anyway guys I have read his posts countless times and did my own side reading. I think I am pretty sure about how to fix the problem! Thanks so much everyone.

However, I do have a question : in the thread, the thread started mentioned an external fuel pump or something in which he did some minor surgery on his car, how relevant is that to my case? Can anyone shed some light?

Shabbeh

Regarding the corresponding part numbers for the spark plug and ignition coil replacement, (because my dealer is a bitch about providing information about my part numbers in my car #) can I just get any coil/spark plug online that claims it fits a 3.0L V6 engine "universally"?

on a side note, my dealer is a serious s*n of a beeeeeeeeeech, he keeps refusing to provide part numbers, do I really have to open up my car to have a look?