SchwarzY2kS4

2000 S4...bone stock with exception of remote start system that the prior owner had installed. Just replaced bad battery as it would not turn over to find battery had bad cell. All was fine for a few days then would not start. At the same time, there was no gauges, or center cluster, radio, climate control, windows, power locks working, as well as it will not allow connection of OBD2 scanner. After fiddling for awhile, everything came back to life, started and ran fine. I then scanned and it logged a 18010 code...intermittent power supply terminal 30 voltage too low and 17866 exhaust temp sensor 2 short to ground. I also have other codes that were there prior to this problem that are related to my deletion of the EGR valves and evap system...I think I have a bad purge valve or gas cap as it hard starts after getting gas. I deleted the EGRs during a valve job/timing belt service a year and a half ago.

It continues to do this about once every five times of starting.

Any thoughts?

SchwarzY2kS4

Problem solved.....I removed the ground wires at the fire wall...behind the coolant reservoir. Although the nut securing them was tight and all of the wire ends did not appear to be very oxidized or dirty, I cleaned them, the contact surface on the nut and the ground lug at the firewall with emory cloth until they were nice and shiny, applied an electrical anti-oxidation paste, and reconnected. All is good now.