timekilling

First post on AudiWorld.

Arrived here looking for info on carbon buildup. RS4 (25K miles in 22 months on Chevron 91) was giving me CELs and I tried to go easy on the service advisor who admonished me to not clicking my gas cap. On inspection it was low fuel pressure in the delivery system and a sensor was out of spec and replaced.

CEL back on yesterday and I dropped it off this morning to get a phone call asking me if it was okay if they added a cleaning agent to the gas and drive it for 60 miles, then wait for a cold restart to check to see if the problem cleared. In the meantime they want to put me into a rental while they sort it out.

I just called for them to stop work to wait for an Audi loaner (they have a 07 CPO RS4 I'll ask for) because I have a feeling the car will be there a while.


In any event, good to be here. Highlights of other cars in my signature. I moderated on another forum for several years and hoping to post more often.

Last year:


Thanks

Reggie

Keep us informed of what they say You might think of getting a VAG-COM so you can read the error codes yourself

silverRS4

Hello and welcome. Nice car. The routine the dealer is going through sounds spot on. They will swap coils and plugs on the misfiring cylinder to see if the misfire follows those items. Next step is to add the VW-Audi fuel conditioner. I think its meant to clean injectors. It may do that, but it won't cure a RS4 with cold start issues. The problem is random and intermittent. Worst case, they start the car in morning and the misfire count is less than 12 and they give you the car back and say its fixed. They WILL NOT remove the manifold on a whim. I believe after the fuel additive and drive and overnight that if it still misfires they start checking the fuel system, namely injectors. They will see if the injectors can maintain the residual pressure in the fuel rails when the engine is off (about 60 psi). If one or more fail, then the next step is to replace all of the injectors. At the point when the manifold is removed, the carbon buildup will be evident and should be cleaned under warranty. Hope it gets resolved, but frankly the Service Manager has to be on the ball or you will just be visiting them again in a few weeks when it happens again.

bruised rs4

Shine the loaner. Have them put the stuff in the gas and give the car back to you so you can drive it the 60 miles. BTW, I doubt that they will give you an RS4 as a loaner.

timekilling

Update: Service Manager called me and they must be used to dealing with the typical Bellevue, WA Audi owner because I got some sighs until I pointed out that I’ve built up Honda hatchbacks for Solo 1. He explained the process (similar to silverRS4's post) that outlines the process that Audi Corp wants them to follow in order to get to the intake manifold cleaning. I'm going to let it play out. Right now the car will sit overnight at their shop after this morning’s run with the additive. I have no doubt these guys will take care of me but I need to let them do it their way.

The Service Manager chuckled at the RS4 suggestion, but if they tried to stick me in a rental I'd point out that the RS4 is my 3rd Audi (+06 S4, +07 A3) and speak to the site manager. Getting a 09/10 A4 loaner, should be fun, but it will probably be an automatic.

Will keep this thread updated.

ELEVENS

Welcome to the board. The RS4 is a really great car. Hang in there, it will be worth it.

timekilling

Update: Audi reports no misfires after 3 cold starts this morning after yesterdays fuel treatment. They made pretty robust notes to set me up for cleaning with needed. The 2010 3.22 loaner was a nice change, but that pretty much went away when I started the RS4.

In any event I'll update if I end up back for codes.

Thanks

GotRS?

I get the morning misfires often, I just clear the codes for now. I did get the injector cleaner once but the parts guy said if I uses Chevron it was pretty much the same. We have 91 octane in CA and that makes it worse for strong starting. The process to get to intake cleaning is just not worth my time right now, the car runs very well after the thunder at start up. The full exhaust adds to the issue I'm sure.

Welcome OP!

timekilling

Update: Had the carbon removed in April under warranty at 32K, RS4 woke up after cleaning, feels much better now. Worried as I approach end of warranty, but the shop foreman said "you need to drive this car like you stole it".

3.2 Q5 as a loaner, nice car, might end up with a 2.0 this year or next as the RS4 approaches 40K, would like to park it during the winter.

Side note: brakes are shot at 35K, having front rotors and pads replaced (my cost, it's a wear item). Will probably change pads every 25K to prevent them from cutting slots into the rotors. Also, service manager let me know they'd replace the shocks under the DRC recall while its up in the air, however I haven’t noticed a problem.

RS4bro

SA is right...you need to drive it like you stole it from time to time! I have heard mostly good things from folks about the DRC recall.