itchiie

Hello! I've been a long time lurker, so I've done a fair bit of research already but I'm at the end of my amateur malfunction analysis here. The car is a 2007 Audi A4 3.2 Quattro with about 70k miles.

I'm getting intermittent CEL codes for
0031 - heater control circuit low bank 1 sensor 1
0051 " " bank 2 sensor 1
0037 " " bank 1 sensor 2
0057 " " bank 2 sensor 2

On occasion I get 2009 - intake manifold runner control circuit low bank 1 and the one for evap system but I failed to write that number down.

In terms of frequency - maybe 1 out of 5 times that I start the car, I get the 4 aforementioned and maybe 1 out of 10 also includes the intake manifold and evap code. When the codes occur, it runs with a rough idle. Applying more than let's say 25% throttle results in sputter sputter cough, poor acceleration and fuel economy as presumably it's failing to utilize a bunch of fuel. Resetting the code makes all the problems go away and the car runs perfectly.

Steps completed: replaced spark plugs, all 6 ignition coils, o2 sensor bank 1 sensor 1 bank 2 sensor 1 (The two accessible from the engine compartment, upstream). Plug and ignition coil wires appear to be intact with no noticeable frays, melts, etc.

My most recent bit of research and super basic applied knowledge is perhaps the fuel pump relay through which the evap system is fed could be the issue.

Thoughts?

itchiie

bump