New to me RS4!... now what?

[Mistro]

So I picked up an 08 RS4 a few months back CPO'd and with a 2 year extended warranty on it. She's got about 78,000km and has been running pretty good so far... but I suspect that coming from a civic, I'm easily impressed.

The only issue's I've had are the idle is a bit rough, and third gear has a slight grind on random occasions when the car is semi warm. The old owner also got a coin stuck behind the ashtray which is kind of annoying too. Second gear clutch engagement is a bit rougher than the civic but for that I suspect that the root cause of that is somewhere between the driver's seat and steering wheel .

I guess my question is, what should I do with it now? The only mods I've done so far are to de-flap the exhaust by plugging up the vacuum lines going to it and some electrical mods.

I've been debating getting it carbon cleaned and got a quote for around $900 (CAD) at a pretty good mechanic shop here. Is there anything else I should get done while the engine is taken apart?

Also, would it be worth changing all the fluids in it just for peace of mind? The car reads 12k km's left until the next service, but I don't know if that's accurate or whether it was just reset it when I bought it. I was thinking tranny (redline?) and diff fluids along with a fuel and air filter change.

Any other words of wisdom?

[B6JoeS4]

Yeah I'd change all the fluids. Could fix the 3rd gear but unfortunately it's probably a bad syncro. Common problem on S4/RS4 transmissions
Trans/diff- Motul Gear 300

I'd suggest doing the ps fluid and brake fluid as well as an oil change. I'd get a carbon cleaning done for sure at those miles. Rough idle is a sign of severe carbon. Severe carbon can cause damage

Mods:
JHM Tune
JHM 2.75 downpipes and catback
JHM Intake Spacers
You'd have a hell of a machine with those mods

[NY07RS4]

Maintenance first so all fluids is a good idea. (engine oil/filter, fuel filter, plugs, air filter, cabin filter, trans fluid, rear diff fluid, brake fluid, coolant) be sure you have the updated coil packs. This could be the cause of the rough idle. CARBON CLEAN would be a HUGE plus. If you fo this route the first mod I'd suggest would be the I/M spacers since you have the I/M off. After all of this you will in really good shape. CPO usually means good rotor and pad life BUT we all know that can be "overlooked" from dealer to dealer.

Fluid might help the gear grinding but it sounds like you may have a worn synchro or two.

More to come but I'd suggest starting with the above.

[PolishPete]

Difficulty 1st to 2nd gear isn't necessarily you. The RS4 is know to be difficult here, however, after my carbon clean, 1st to 2nd gear was easy. Others have said the same. For whatever reason, as the carbon builds up, it makes it difficult to go from 1st to 2nd easily. Some have even thought that they suck at driving stick, when in reality, it's the car causing the problem. However, carbon clean fixes it. (temporarily of course, because as the carbon builds back up you'll slowly recognize the problem coming back).

[Krys-RS4]

Difficulty 1st to 2nd gear isn't necessarily you. The RS4 is know to be difficult here, however, after my carbon clean, 1st to 2nd gear was easy. Others have said the same. For whatever reason, as the carbon builds up, it makes it difficult to go from 1st to 2nd easily. Some have even thought that they suck at driving stick, when in reality, it's the car causing the problem. However, carbon clean fixes it. (temporarily of course, because as the carbon builds back up you'll slowly recognize the problem coming back).

How long does the "carbon clean-benefit" last for???

[dparm]

Well it's a slow process. You won't notice it much, but someone who hasn't driven it in a year or so will notice it feels a bit down on power at high RPM. Certain oils seem to be more buildup-resistant but you cannot truly "stop" it from happening, as of right now. Fuel system cleaners do not work like they would in a port injected motor (like the S4). All I can say is you should just budget to have this done periodically. Put some money aside each month for your "carbon cleaning" fund.

As for your original question, I would just do the whole shebang: engine oil, trans oil, diff oil, brake fluid, clutch fluid, coolant, power steering fluid, spark plugs, engine air filter, cabin filter. Shouldn't take more than a few hours, but before spending the time and money the dealer should be able to look up when this was all done since it's CPO.

I would get the battery tested too, especially with winter coming.

[zachf88]

For trans fluid, go with Liqui Moly 75w-90 GL4+. I was able to order some to Nova Scotia about a year ago. I also added the Liqui Moly MOS2 for gears. For the difs, go with Liqui Moly 75w-90 GL5.

Power steering probably needs to be changed, but you can do this easily yourself. Just get a plastic silicone tube (home depot in plumbing isle) and a plastic oil syringe (Walmart auto section) and just suck all the oil out into a waste container, poor new stuff in. Turn on car and do several right to left, lock to lock with the steering wheel. turn car off and extract all the fluid and start the whole thing over again. I usually do it 3-4 times, about every 5-7k miles. When I first changed the power steering fluid, it was so gross with only 15k miles on it. Oh, and use only OEM power steering fluid.

As for mods, the apikol rear dif mount is pretty good bang-for-your-buck. Doesn't add power, but does clean up a lot of dif slop.

Brake fluid should be changed every 2 years, no matter the mileage.

Hope this helps!

[Mistro]

Thanks for the tips guys. Looks like a carbon clean will definitely be on the list of things to do. How often should a carbon cleaning really be done? It's not a daily driver so I'll probably only put on maybe 8000kms (~5000mi) a year based on the rate I'm going at now. I do drive it fairly "spirited", but the majority of my trips are unfortunately quite short (10-20km). The engine oil is usually warmed up around the normal ~100-120C half way through the trips though.

zachf88 - You mention that the power steering probably needs to be changed? Is this a common problem or just something you noticed? I haven't dug through the forums in any depth about this, but I don't recall seeing anything during my daily browsing.

For Trans/Diff I'll compare:
Liqui Moly 75w-90 GL4+/GL5
Motul Gear 300
Redline

Engine Oil - I was reading up on some of the forum posts regarding engine oils. I was thinking of going with just Castrol GTX like most dealers around here do apparently, but dparm mentioned that some are more resistant to carbon build up? Are there any particular properties I should look for? I don't mind spending a bit more if it means it'll take a bit longer to gunk up again.

PolishPete - haha thanks, I thought it was just me not being smooth enough for the car. Hopefully things improve after the carbon clean.

Also, do you guys recommend getting winter wheels (tyres + steel rims) that are the full 19" size, or something smaller (18"? would still fit the brakes?) with a bigger sidewall?

[USCGTO]

carbon clean is something pretty much everyone must do ...

+1 on the battery getting tested for the winters..

[karsty]

Also, do you guys recommend getting winter wheels (tyres + steel rims) that are the full 19" size, or something smaller (18"? would still fit the brakes?) with a bigger sidewall?

Winter wheels are a good idea. Save yourseld the cost of switching tires on your stock wheels in the Spring and Fall every year. I doubt you'll find a steel wheel that will fit over the front calipers, plus it would loook ugly. I would find a low offset 18" wheel that will fit over the front calipers. An 18" tire will provide a bit more cushion in the winter and if you get an 8" wide wheel and a 245mm wide tire, you'll have a bit of wheel protection as well.

[zachf88]

zachf88 - You mention that the power steering probably needs to be changed? Is this a common problem or just something you noticed? I haven't dug through the forums in any depth about this, but I don't recall seeing anything during my daily browsing.

No common problems, but in the long run, it'll pay off. Steering pumps go prematurely on vehicles like these. Just preventative, and especially since the oil gets pretty damn dirty!