Hello! I'm very new to this forum, but have been reading it for a while now. Today I became a happy owner of a 1997 Audi A8 Quattro, but it has a few issues. I tried researching it but was not able to find all the answers. Please answer them if you have the time.

-I have multiple misfire codes. Basically, 6 cylinders are misfiring and I have 7 codes total. The previous owner said that the car is in need of new spark plugs. Do you think that replacing the spark plugs would resolve the issue? I'm going to replace the spark plugs anyways, which brings another question - which spark plugs should I get for my Audi and do I need to re-gap them?

-The car is missing it's air bag. I found a S4 steering wheel with the bag but I don't know if it will fit on my A8 okay? Could anyone verify it, please? I believe the S4 is from 1996.

-Since the car has 139,000 miles on it, I was thinking about running Sea Foam through the engine + gas tank. Do you think that it's a good idea? I've "seafoamed" my other cars (Saabs and VW's) just fine and it seemed to make things better, but I'm not sure if Audi A8 would like the treatment or not. Has anyone tried it before?

-My brakes are barely working. Long story short, the previous owner poured the power steering fluid into the brake fluid container and now the brakes don't work properly. I have to slam on the pedal in order for the brakes to work at all. Does anyone know if I can just "flush" the brake system or do I have to replace the ABS module? Could it be unrelated to the wrong fluid and that I maybe need to replace the brake booster?

-The car is missing the front bumper. Would anyone know where I can get one? I've tried calling a few junk yards in WA but none of them seem to have them + they said that when they do have them in stock, they sell them for $1,000 (!!!)

Some General Questions:

What would be a good start as far as maintenance goes? I intend on keeping this car for many years to come. How long do they usually last? And what oil would you suggest that I use for the future?

Thank you very much in advance and have a wonderful day!!

 

UPDATE:

I replaced all 8 spark plugs with Bosch Platinum 4 and reset the trouble codes. The car is running a little better, but still not perfect + I still have 1 code which is "P0304 - Cylinder 4 misfire". The car vibrates at idle and whenever I'm roaming slowly, sometimes it vibrates like crazy + doesn't pull at all. It's very frustrating.

Also, the previous owner got rid of the air box (where the air filter is) and replaced it with the "cone" looking filter that is attached directly to MAF.

If anyone would please help - I would really appreciate it. Thank you very much!

UPDATE 2:

Every now and then the car dies but starts right back up. Also, the flashing oil light (or image, to be exact) appears on the main screen every other trip, but whenever I check the oil level, it's full and is pretty clear. I already dumped Sea Foam in the engine (the oil light issue has been happening before then) hoping that it will clear some gunk up and bought 8 quarts of Mobil 1 full synthetic oil so I will do an oil change in 200 miles. In the meantime, I want to figure out what is going on with my poor engine...

Thanks guys!

 

Hello , I recommend to move the coil to another cylinder and see if the problem move if the problem move to another cylinder you have a coil problem if not move ck the coil wire connector I know they have problems with the connector .

 

Your hydraulics in the brake system are pretty well destroyed by the power steering fluid. Flush out the old stuff completely and replace the flexible brake lines. If this does not help, which is likely, you will have to replace the master cylinder, brake calipers, and probably the ABS mechanism. Get re-manufactured parts as parts from an Audi dealer will cost as much as you paid for the car. Fix your brakes before you need to be fixed after you slam into a tree. Good luck.

 

Thanks for the input. I have moved the coil to 2 different cylinders and the trouble code have followed the coil, indeed. So there we have it - a bad coil. Going to a junk yard on Monday to pick up the part.

Also, as far as brakes go - it turned out that the vacuum line has come off the intake manifold causing the engine to run very poorly and brakes not to work. After re-connecting it, the car runs very nicely (aside from 1 dead coil) and brakes work like a dream, believe it or not.

Next step is to find the front bumper + turn signals.

 

Got additional news:

The car stalls at it's own will randomly. Could be a second after starting her up, or in the middle of the road. Mainly when I'm slowing down though. Going to look into the air lines tomorrow and see what the heck is going on.

Also, the flashing oil light that comes on randomly also - going to pull out and clean the oil pressure sensor and see if it solves the problem.

Now there's a broken sunroof motor, among other things such as sagging suspension, etc...

Good grief! More fun for me though...

 

you need to clean the sensor on the bottom of the oil pan and ck your oil pressure

 

Guys! I've managed to fix the majority of car's issues, but I still have a few more issues left so please help.

1) I need to know how to "reset" the sunroof. I've installed a new motor assembly and now whenever I turn the switch, the roof goes up and down right away. A DIY would be highly appreciated.

2) I want to do a transmission flush. Do I have to use the super expensive Audi fluid or can I get away with something similar? Also, I was told to drop the transmission pan and turn the engine on, which will drain everything, including the torque converter, then replace the filter, screw the pan back on and pump the transmission with new fluid with the engine running until there's no more room. Is this correct?

3) My car is getting TERRIBLE gas mileage - 12 mpg average, including highway - what could be the issue? I was told that my A8 should be getting at least 20 mpg average and around 28 mpg highway.

4) How can I disable my built in phone? It's missing and whenever I turn on the car, there's a loud "BEEP" and it's very annoying.

Thanks for your input, it's highly appreciated!!

 

Woohoo... After days of hard work and lots of searching for parts, the majority of the problems have been solved - the car is almost complete now. These are the few things that I need to finish before I can call it done:

1) Replace the front bumper + driver's side turn signal
2) Replace/fix the Cruise Control module - nothing happens when I try to use it
3) Find out why the rear window defroster doesn't work at all. Fuse? Wire problem? Hmm...
4) Replace the top 2 Oxygen Sensors - what a pain on this engine! Any suggestions for easier replacement??
5) Transmission flush - can't wait to see what the old fluid looks like...
6) Replace the rims with 17" Premium Audi wheels that came as an option on this model.
7) Replace the fan clutch - it's making a loud knocking noise - sounds terrible...

This should summarize it. Does anyone have any suggestions/tips on how to easy my life while I'm at it? Any help is appreciate it. This is my first Audi A8 so I'm doing as much research as I can. So far so good.

Thanks!!