iSynthetixx

Okay, first the facts.

2008 S5 6-Speed 62,000 miles not under warranty
Just had all the spark plugs changed, an ignition coil changed, Carbon Clean and chemical clean of the intake. Ran the Audi recommended injector cleaner through 3 tanks of gas, alternating a regular tank in between each. I only run 93 at the pump the entire time i've had the car (purchased in August 2014), I'm the second owner.

So, about two month ago after going out of town for 2 days I came home and started my car and it started idling VERY rough. Engine was shaking (like misfires) and the RPM's were sputtering between 1200 and 600. After warming up for a while the shaking stopped and the RPM's stayed at about 1100. Check engine light was on. So I took it to the dealer. Note the car drove fine and accelerated fine once it was driving the issue was with it idling. When you turned the AC on or turned the wheel while it wasnt moving (put a load on the engine) the RPM's would drop significantly.

Fault code were for misfires on cylinders 3 &6 as well as a random misfires code. Dealer replaced all spark plugs and chemical cleaned the intake and replaced an ignition coil. $700 in total. I get the car back and its running normal again for 2 days. Two days later I start it up in the morning and all the same symptoms are back. I take it back and they want to do the carbon clean and change all the injectors ($3800 total. $1000 for the carbon clean, $2800 for the injectors). They tell me to run some injector cleaner through a few times, and I have, no luck.

So, I took it back and had them do the carbon clean (negotiated it to $850 since the first $700 didnt fix it and for the hassle). Get the car back and its running perfect for about 4 days. Idling at 600 rpms and no signs of any of the same problems.

This morning I start the car and all the same problems again. Rough idle, loss of RPM's when i put a load on the engine, and it idles at about 1100 instead of the normal 600. I dont know what to do. I'm afraid the deal has no idea what the problem is and I dont want to spend another $2800 on injectors just to have all the same problems come back. Does anyone have any idea what may be the root of the problems or can provide any insight at all or even if $2800 to do all the injectors is a fair price???

Kris Hansen

Were the only codes for the misfires?

iSynthetixx

I believe along the way (the computer was reset many times during this process) there was a code for the throttle body due to a higher than expected idle and an engine mount solenoid. I dont have the printout with me right now.

iSynthetixx

bump

Kris Hansen

You need to have the codes, and better yet, bring it to a shop that can help diagnose it..