Bartenderfloyd

I'm approaching 55,000 miles and I like to do these services myself. I am going to change the spark plugs and V-belt and have some questions:

1. Spark Plugs - Should I change the coil packs as well? I'm from the school of "if it isn't broken don't fix it" but sometimes the extra maintenance is recommended.
2. V-Belt - I have searched here and on YouTube and can not find any info on how to change this belt. Does anyone have a DIY?
3. V-Belt - Are there any other replacement recommendations like tensioners or whatnot to go along with this maintenance?

Any info is appreciated.

raaizin

Here is a diy for a C6 pulley, might help with the vbelt it may be similar.

https://www.audiworld.com/forums/a6-...ulley-2884201/

there is a diy for plugs on the C6 forum as well it might be worth a look

tenspeed

1. Spark plugs. Don't change the coils unless they fail. You might want to keep a spare coil in the garage for replacement or testing.

2. Maybe YouTube has one or check in the C6/C5 sections.

3. Most tensioners should make it to 100,000 miles. The spring weakens and the belt will squeal on the alternator after start up.

Worldwidebeagle

I agree. Make sure you have some 3M silicone grease and put a smidgen on the porcelain insulator so the coil slides back on nicely and fully. Only use NGK plugs. They are the factory plugs - Bosch is just an back up supplier.

I am not sure if you need to keep a spare coil pack for 3.0 C7s. The diagnostic computer is so sophisticated, VAGCOM will tell you which coil is bad.

I use the 3M silicone grease for many things - including brakes. 3M 08946 Clear Silicone Paste - 8 oz.

Replacing the accessory belt so soon? (I assume that one and not the Supercharger).

I assume you have already done air filter

a44mark

I'm about to do the V-belt soon as well, since I too am approaching 55k miles. I also just posted a DIY on the spark plug replacement - pretty straightforward. In fact, I changed the plugs on my wife's Mazda CX-9 a week later and they were much harder to replace.

As said above, leave the coilpacks alone until they fail - they used to go often on my old 2002 A4, but once they got the recipe right they lasted several years.

I'll probably get to the V-belt replacement next weekend (I hope). I'll try to take pics and post a write up afterwards.

-Mark

a44mark

I was originally confused about this, but the schedule calls for the supercharger belt to be replaced at 55k and the accessory belt at 75k. But it refers to both as a V-belt... you have to read closely and note which is the "front" V-belt, and which is the "rear"...

I bought both, so I'll probably replace them both at the same time to save the hassle next year.

-Mark

Bartenderfloyd

I saw your write up and it was awesome. I'll be using it as a guide. I will be replacing the V-Belt (supercharger belt) as well. I was hesitant about the tensioner but from what I've seen it looks like any other tensioner I've seen. I'll try posting a DIY as well.

dshahs420

Why does Audi recommend changing the spark plugs at 55K miles? What brand are OEM plugs? If they are NGK Iridium don't most last at least 90K??

JRomulus

I had the rest of the 55K miles maint. done last week.
When the plugs were changed, I got an immediate >10% increase in MPG.

I am having the front belt changed this week (at (every) 55k miles) it says:

"– replace only the belt for the compressor drive (front belt)"

The other (rear belt) looks like every 75K miles.

BillBoost37

Lasting 90-100k miles is different than performing their best at those mileages. I have found that all plug gap will widen over time. I just did mine at 98K and assume they would have been done already.

On the belts, personally.. I plan on buying both belts and tensioners because I found the belts on mine to be Dayco and that's not cool in my book. Next time I put the car into Service Position... I'm doing a solid bit of work considering the effort it takes to get into Service Position.