2007 Audi S8 172k miles - Audi Forums
Audi A8 and S8 Forum Discussion area for every generation Audi A8 and Audi S8. (Audi A8 Forum, Audi S8 Forum)

User Tag List

LinkBack Thread Tools Display Modes
post #1 of 2 (permalink) Old 03-16-2018, 07:10 AM Thread Starter
Join Date: Nov 2017
Posts: 2
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
2007 Audi S8 172k miles

I recently had my car in the Audi shop. It was misfiring and they replace the driver side valve cover and Gasket and the passenger side gasket for the valve cover. After $1,600 my car was still misfiring. They suggested that I get intake valves clean new spark plugs new coil packs and gaskets for another $1,600. Still afterwards cylinder 10 was still misfiring they suggested a new intake manifold cover because of the leaks causing the fuel mixture to be off causing the car to be in the lien position?? And to replace the fuel injector and cylinder 10 but would like to do all fuel injectors and seals for another $2,300. Is this car worth another $2,300 in the engine.
Kd5vip is offline  
Sponsored Links
post #2 of 2 (permalink) Old 03-27-2018, 09:54 PM
Join Date: Mar 2018
Location: Pittsburgh, PA
Posts: 4
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)

That's a lot of money to throw at a car to maybe fix the problem. My impression is that your engine hasn't had much care over its life.

I would recommend getting either a gadget that plugs into the OBDII socket and gives you some actual data, such as the fuel trims and other readings OR a VCDS cable from Ross that will attach to a laptop and let you have more control over the engine management. I use this one for convenience:

Actron CP9600 U-SCAN OBD II and CAN Wireless Smartphone Interface

If the engine is indeed running lean then you can readily suspect an air leak somewhere. These can be easy to find or they can be hard. You can check every hose and connection yourself. If a vacuum hose looks the slightest bit cracked, replace it. Next, search for the location of your PCV valve and it's associated brittle plastic parts. If cracked, you can swap them out. If your gadget still shows a lean condition, then get the engine "smoked" by someone that has the knowledge to do it right. If the intake is leaking, the smoke will show you. All this that I have said so far should cost you about $100 and a little time.

Plugs and coils are well worth the cost on an engine with your miles. Fuel injectors? I would first change the fuel filter, then use good fuel injector cleaner in 2 consecutive full tanks of gas. I did that with my S4 and felt the difference immediately.

If you are sure the injector for cylinder 10 is bad, it's not too hard to swap out. In fact, you can pull all of them out, send them away to be rebuilt, and reinstall them. They cost about $12-$20 each to be rebuilt that way. Watch some youtube videos and see if you can do it.

Good luck, my friend!


2008 S4 Cabriolet 6-speed manual 1 of 2 in US
iselinzilla is offline  
Sponsored Links

  Audi Forums > Audi Models > Audi A8 and S8 Forum

Quick Reply

Register Now

In order to be able to post messages on the Audi Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome