S8 started running like crap.
12-13-2017, 03:56 AM
#11
AudiWorld Member
Thread Starter
Will do.
Waiting on parts to arive. I am kind of sceptial about spark plugs that all of a sudden all 3 went out. I hope so, but I think I have to bite the bullet and preform carbon cleaning in 20 degrees weathere.
12-13-2017, 09:25 AM
#12
AudiWorld Member
Join Date: Oct 2012
Posts: 145
Likes: 0
Received 0 Likes
on
0 Posts
I did mine this summer not long after buying the car, its time consuming but not difficult at all.
I am sure you have looked into it, if I can offer some advice having done it is, replace the oil filter O rings whilst your at it. They consistently fail and cause oil leaks and only cost a few $, but a PITA to replace as you have to remove the intake manifold. if your doing a carbon clean its another 5 minutes work. And if your going to keep the car, possibly look at the valve cover gaskets, again easier to do with the IM parts off and known to fail.
I am sure you have looked into it, if I can offer some advice having done it is, replace the oil filter O rings whilst your at it. They consistently fail and cause oil leaks and only cost a few $, but a PITA to replace as you have to remove the intake manifold. if your doing a carbon clean its another 5 minutes work. And if your going to keep the car, possibly look at the valve cover gaskets, again easier to do with the IM parts off and known to fail.
12-15-2017, 01:07 PM
#13
AudiWorld Member
Thread Starter
I did mine this summer not long after buying the car, its time consuming but not difficult at all.
I am sure you have looked into it, if I can offer some advice having done it is, replace the oil filter O rings whilst your at it. They consistently fail and cause oil leaks and only cost a few $, but a PITA to replace as you have to remove the intake manifold. if your doing a carbon clean its another 5 minutes work. And if your going to keep the car, possibly look at the valve cover gaskets, again easier to do with the IM parts off and known to fail.
I am sure you have looked into it, if I can offer some advice having done it is, replace the oil filter O rings whilst your at it. They consistently fail and cause oil leaks and only cost a few $, but a PITA to replace as you have to remove the intake manifold. if your doing a carbon clean its another 5 minutes work. And if your going to keep the car, possibly look at the valve cover gaskets, again easier to do with the IM parts off and known to fail.
12-16-2017, 08:57 AM
#15
AudiWorld Member
Had multiple misfires always on the same cylinders on my '08 S8, Replaced all coil packs as they are known to fail + spark plugs and noticed oil in the plug tubes comming from valve cover gaskets so replaced them at the same time. Been running smooth ever since.
12-16-2017, 10:03 AM
#16
AudiWorld Super User
I'm thinking this also. Had similar issues with my Q5.
12-16-2017, 01:37 PM
#17
Repeatable misfire ( & under load ) sure - coil pack. Just did one in our Volvo a few years ago.
The likely thing that will create a random/moving misfire is combustion issues (fuel/air mix). Fuel filter restriction is a prime example of that. Or O2 trim
The likely thing that will create a random/moving misfire is combustion issues (fuel/air mix). Fuel filter restriction is a prime example of that. Or O2 trim
12-20-2017, 05:54 PM
#18
AudiWorld Member
Thread Starter
Decided to do some investigating today before I get new spark plugs. So I have misfire on cylinder 1, 2 and 6. My first step was to switch coil packs with cylinder 3 and 4 that I know work, no change still misfire. Then I switched spark plugs, still cylinder 1 and 2 misfire. I think I have no choice but to do carbon cleaning. From reading around, some people have mentioned about clogged injectors. When I puled the spark plugs cylinder 1 spark plug had some fuel on it, number 2 was dry. What do you guys think? Thanks
12-20-2017, 06:13 PM
#19
AudiWorld Member
Only thing that's stange is that you should'nt have gas on your spark plug if it's working, should be dry as it fired and burnt the fuel. So might be plug #1 is not working or #2 injector is at fault...considering the work i'd go with spark plugs before replacing injectors,
MP am i making any sense?!?
I had the same problem on my '08 S8 and decide to replace all spark plugs + coils and it's now running better than ever...
MP am i making any sense?!?
I had the same problem on my '08 S8 and decide to replace all spark plugs + coils and it's now running better than ever...
12-20-2017, 06:31 PM
#20
AudiWorld Member
Thread Starter
Only thing that's stange is that you should'nt have gas on your spark plug if it's working, should be dry as it fired and burnt the fuel. So might be plug #1 is not working or #2 injector is at fault...considering the work i'd go with spark plugs before replacing injectors,
MP am i making any sense?!?
I had the same problem on my '08 S8 and decide to replace all spark plugs + coils and it's now running better than ever...
MP am i making any sense?!?
I had the same problem on my '08 S8 and decide to replace all spark plugs + coils and it's now running better than ever...
but i switched the plugs and still the same misfire on cylinder number 1. If it was the plug cylinder 3 would have misfire.