!! FINALLY FIXED !! - well mostly
Finally fixed at least one of the faults on my A2
After much effort, at least one visit to the local Audi dealer (they couldn’t find the fault after an hour of fiddling) and a few expensive new parts I have finally fixed one of the fault codes I have been getting;
17912 - P1504 Intake Air System: Leak Detected
Well would you believe it,... it actually turned out to be an air leak!
Feel really embarrassed
I checked the car over so many times, checked all the hoses (all in really good nick), for other reasons I replaced the MAF, the lambda probe, 2 coil packs (getting misfires), air filter, spark plugs and removed the inlet hoses up to the throttle valve many times with no success fixing the rough idle, error code or poor performance.
My mistake (and possibly the Audi engineer's too) was to take too much notice of schematics. Elsawin is a great source of info on what hoses connect to the inlet manifold - except the one that had split on my BAD engine. Its just not identified on the drawings of the inlet manifold!!!!!
There is a hose connected to the lower manifold at the back low down where you can’t see it. In fact I could only see it by getting right under the engine (the drivers side and looking up at it). I can’t remember what it does but it’s connected to a valve that uses the vacuum to do something. Anyway in my case the hose had split at the top and the split was not visible until the hose was actually removed from the manifold so even if you were looking up at you wouldn't know it was split without feeling all round it.
When I went to Audi to get a replacement hose (its not available separately - all part of the valve assembly £67 inc vat) it didn’t appear on their ETKA system either. We had to search under the breaking system to finally identify it...
Managed to cut off the split end and reconnect without replacing it so job done...
Morale of the story;
Don’t believe the diagrams!!!, spend time really looking and in my case blow down the inlet manifold and listen for the hiss.......
Still not fully fixed all the issues - my lambda readings are still out, but a nice way to close this chapter
