Thoughts on code the car has thrown...

So my A4 has thrown this code twice now in a 2 week period… Both times it seems to happen if I start the car and let it run w/o driving it for 10-15 minutes while it warms. I’d think it runs rich when in that state not lean?

Anyway, car has 123K miles and is fairly well maintained. Coils and plugs have less than 5K on them. Fuel injector? I’d think I would see more issues than the below. Could it be an emissions thing? Car drives fine… I just cleared it again and we’ll see how long it take to come back… lol Thanks!

1 Fault Found:
008583 - Bank 1; System too Lean at Idle
P2187 - 004 - - Intermittent - MIL ON
Freeze Frame:
Fault Status: 10100100
Fault Priority: 0
Fault Frequency: 7
Reset counter: 255
Mileage: 197898 km
Time Indication: 0

         Freeze Frame:
                RPM: 744 /min
                Load: 22.0 %
                Speed: 0.0 km/h
                Temperature: 62.0°C
                Temperature: 3.0°C
                Absolute Pres.: 990.0 mbar
                Voltage: 13.081 V

Readiness: 0000 0000

That code is most likely caused by a vacuum leak. So there is probably a damaged vacuum line somewhere. I would start by looking at the PCV hoses and then check the vacuum lines. If you have some starter fluid or carb cleaner then spray that over the PCV/vacuum lines and watch for the short term fuel trims (should be mvb 33) to go really negative, like -25%. When the fuel trims go really negative then you have found your leak.

Which engine do you have? The 1.8T or 3.0?

Jimmy, Thanks! Was hoping you’d chime in and actually thought about pm’ing you… lol Yeah, sorry it’s the 2.0T motor… So a vaccum leak, eh… sigh, it’s cold out I don’t want to go look… lol I’ll see what I can find…

Not a problem man.

If your A4 has a 2.0T engine then it isn’t a B6 A4 unless you have heavily modified it. Is it a B7 or a B8?

Try loosening the oil filler cap and removing it while the engine is running at idle. If you can’t open the oil filler cap then your PCV value has likely failed. That was a very common problem with the B7 A4 2.0Ts and the part was revised from revision C to revision P. They go in alphabetical order so that is a lot of revisions!

prime. Do you leave the car outsde and start it when its cold and let it sit outside to warm up

LOL! Nah it’s the beater… Sorry, I always thought it was a B6, but it’s a 2006 A4 with the 2.0T so I guess that makes it a B7, my apologies…

I’ll give the above a try… I did look at the vacuum lines and didn’t see anything all though I spent about 5 minutes looking… It’s supposed to warm up a little this weak so I’ll look closer and try the above… I cleared it yesterday and drove it to the store and then to the bus stop this morning and it hasn’t come back on… yet… lol Thanks man!

Yeah the car sits outside… I usually don’t start it in advance of leaving but it was really bad a few days the past couple weeks so I had to shovel so my wife could get out and I started it those days and it seems like those are the days it popped up, at least I’m fairly certain…

Again, not a problem man. I just like to be sure when I give out advice because the same fault code could be caused by something totally different from one chassis to another. Since I work on everything from B5 A4s to the latest B8.5 A4s, it can get confusing. For example, there is a fault code for boost pressure negative deviant (I forget the P code number). If it is a B7 A4 2.0T then the diverter valve probably failed because they revised those things like four times. However if that fault code comes up on a B8 A4 2.0T then the turbo itself probably failed because they came with the most up to date revision diverter valve from the factory.

Back to your car. With that P2187 fuel trim too lean at idle then I can almost guarantee that the PCV valve failed. I have replaced a couple hundred B7 A4 2.0T PCV valves because of that code. If you do replace the PCV valve then also get the updated line that goes with it too. There is a U shaped hose that goes from the PCV valve to the intake manifold.

OFF TOPIC EDIT: I was actually looking for a B7 A4 2.0T manual as a beater for work. Most 2.0Ts get like 30 mpg on the highway. That is fantastic compared to my current vehicles.