Audi42LV8

How can I do a tune-up on my 4.2?

Also, what are some good spark-plugs? NGK Iridium's good? What do you use?

4Driver4

Technically, there no such thing. The only way to "tune" your car is with firmware changes.

SloopJohnB@mac.com

The air filter can be deceptive...I replaced air filter on the 00 4.2A6 even though the old one looked reasonably good, not very dirty, had maybe 22K on it.

The car woke up. Haven't checked mileage yet but the performance change was worth it. Used an amsoil air filter.

One tip...remove the entire airbox when changing the filter...it makes it a LOT easier to work the clips back onto the top of the airbox.<ul><li><a href="http://www.amsoil.com/catalog.aspx?code=EAA239-EA">http://www.amsoil.com/catalog.aspx?code=EAA239-EA</a</li></ul>

raudi6

My tune-up can also be considered general maintenance. Here are some of the things I do to keep my C5 well tuned.
-oil and filter change, including drain plug (go with a ECS tuning magnetic plug, full synthetic only, i use Castrol 5w40 for Euro
-air filter, I have a V-flow intake, so I remove and clean, recharge
-plugs, I use irridiums and have had reat results (about every 30k)
-fuel filter, easy to change and will improve mpg and throttle response.
-throttle body adaptation (with VAG-COM or search for instructions on how to do a manual adpat)
-remove and clean throttle body, be extra careful.
-remove and clean all electrical connections.
-MAF sensor cleaning (with MAF spray at any part store)
-rotate tires, check psi
-power steering flush, very simple and will save you $$$$ on a new power steering pump. Use OE fluids only.
-coolant flush, same as above.
-brake fluid flush, same as above.
-run some NOS booster or seafoam with full tank of 93octane
-consider a seafoam carbon treatment through intake (beware, you may find yourself erplacing o2 sensor if you over do it)
-pressure test
-check all hoses and tubes (replace as needed)
-if you have 2.7t, clean out ic's
-if you have Forge DVs, clean and relube, consider psi and spring pressure rating
-timing/serp belt and water pump change (dont forget the secondary pump.
-replace differential lube, go with redline gear oil (fairly easy DIY, search for instructions), hardest part is finding the rght tool)
-check and replace fuses as needed.
-adjust BOSE fx
-if you can afford it, have tranny fluid flushed with new pan and filter
-spray door hinges with white lithium grease
-top off window washer fluid
-replace wipers, bad blades can damage wiper motor i think
-fix that d*amn cup holder that keep braking
-brake pads and rotors, lube caliper slides
-if your savvy, hook up control arms with grease fittings and lube

Finally, take her to the car wash and do a full detail, its time for that spring cleaning. Then pay for a dyno and VAG map. While your there reset codes and recode tip to 00032 (sport mode with 1st gear)

Good luck and have fun getting you hands dirty. These things are not in any particular order. Budget, time, vehicle conditions, mileage, shop availability, and other factors will determine what you do first.

PEACE. J

raudi6

so obviously many of the tune-up tips are non-applicable. Hope I gave you some ideas though. How about adding a supercharger. I love forced induction! It works my friend. =)