Electrical hell yet again

A6 All/ S6 All
#1

Hey guys I have my newer audi s6 2008 120k is having electrical hell just like my 2007 one back a while ago.

The relays in the engine bay on the driver side the one for the fuel pump and ecm power supply relay were getting hot and stalling the car. It would turn off and not try to start up until it cooled. I confirmed this by immediately swapping it out and it started instantly. They no longer seem to get hot anymore.

Only the relays under the driver seat the terminal 15 relay and ecu power supply relay are both getting hot. I did swap them out with aftermarket one and it got hot again. I plan on trying genuine ones to see what happens.

I didn’t get to scan the car yet with a ross tech but the only obvious code with my hand scanner under engine 1 is engine mount on the passanger side that is open circuit. The wire is definitely fine to it but I’m pretty sure the mount is bad from the obvious shaking on that side

Ps relays act up after hour and 30 mins of driving

Screenshot_20240311_104643_Chrome
Screenshot_20240311_104643_Chrome1440×1889 192 KB
Screenshot_20240311_104656_Chrome
Screenshot_20240311_104656_Chrome1440×3088 347 KB
Screenshot_20240311_110411_Chrome
Screenshot_20240311_110411_Chrome1440×2429 305 KB
Screenshot_20240311_110424_Chrome
Screenshot_20240311_110424_Chrome1440×2770 252 KB
Screenshot_20240311_110428_Chrome
Screenshot_20240311_110428_Chrome1440×2615 242 KB

Any help would be greatly appreciated it!

#2

I’m not sure if the engine mount is causing it but I’m clueless lol

#3

Turned out the alternator was over charging the car and caused relay to burn out

2 Likes
#4

OMG… Great find. How did you come to that conclusion?

#5

The voltage was running crazy high in the car and the vcds saying the battery voltage regulator in the trunk or aka the negative was messed up from it so i tried changing that first based on me researching that it can also cause that.

After all that the voltage was still high and burning the power supply relays to the engine computer. So I decided it was the alternator. As I was waiting for the new one to come. The car started undercharging instead of overcharging so all the modules now weren’t getting enough power. As soon as I changed the alternator. All is good.

I also decided to change water pump and whatever gaskets like the oil cooler or whatever I could access with it off since I had the front off. I managed to do it without disconnecting the power steering lines or the ac condenser thankfully

1 Like
#6

It literally took me about a month and half to figure out and after fixing it I drove all the way up to Vermont to see the eclipse. It was about 800 miles total from LI NY. Everything is working smoothly so far

20240408_152831
20240408_1528312252×4000 1.16 MB
20240408_152830
20240408_1528302252×4000 1.16 MB

2 Likes