J_Bigs33
04-07-2019, 08:05 PM
Current problem child is my bone stock 2012 S4. A month ago I accelerated fast from a stop light and had the ESP light come on. Got to where I was headed and parked the car for an hour or so and light cleared itself. Got going to the next place I was headed and midway there the ESP light comes on again, this time the check engine light also comes on and is also flashing at one point and now I notice between 1100-3000 RPM's I get what feels like a bad plug or coil misfire. Car runs solid in the higher R's. Noticed fuel mileage sucked. I think I put a half a tank in it that night and maybe put 80 miles on it and it was dipping into the red. Even on my hardest days of driving I don't even see it disappear that quick! I get home and it sits overnight. Call the dealership that morning and schedule to get it in and let them and the warranty company figure out what's wrong and repair. Car has been maintained to a T and always ahead of schedule as well. I replaced the spark plugs @91k. Just had the oil changed 1K miles ago. 105k on the odometer at this point.
Dealership calls me and tells me that warranty company sent an inspector to come out and take an oil sample. Audi service advisor says they got codes P262900 (o2 sensor bank 2 sensor 1), Cyl 4,5,6, misfires and P049100/P049200 for the secondary air injection Banks 1&2 Insufficient Flow. They tell me that's something Audi will cover but they can't do it until cars running 100%. They clear the codes and go out and drive it and get it to act up like it was for me. They re-scan and get a cylinder 5 misfire. They swap coils and plugs around to see if it'll misfire on a different cylinder and it doesn't so they rule those issues out. They speculate at this point that it's a bad injector or a broken valve spring at that cylinder. They need the warranty company to authorize the next step. Turns out that my warranty after 100k goes to a "powertrain only" warranty and does not cover injectors. They are convinced that it's a broken valve spring and want to pull the valve cover. Warranty wants maintenance records. I had some in car and the rest at home. They only send what's in the car so of course my warranty company denies the claim due to "lack of maintenance". I spend the next week going round and round with them, sending them all of my records I have on everything I've done and finally get them to re-open the claim and let me get a second opinion once they realize this cars been more than maintained ahead of the normal intervals.
Since the injectors wouldn't be covered and a lot of the other shops I called to pick their brains, said this definitely sounded like an injector issue. I decide at this point I got nothing to lose. I'm pretty mechanically inclined and have been in the auto industry for nearly 22 years in parts and service so I figure this is something I can tackle. Take the car to a friends shop and we decide to start at square 1. Pull the plugs, inspect them (only 13k since I replaced them) no fuel saturation, all looked good so I swap plugs/coils from bank 2 to 1 and 1's to bank 2, clear codes and go out and run it again and cyl 5 is misfiring. Pull the supercharger off and intake manifolds and remove injectors. I separate #5's injector so when I take them into the shop whose going to test and rebuild and re-test can tell me if anything's abnormal with that one in particular. Get them back and nothing abnormal on any of them on the paper work. Replace the upper and lower manifold gaskets and plastic coolant bypass, injectors back in and button it up. Go out and still same issues[headbang]. At this point I proceed to have another shop who specializes in German cars and Audi's specifically proceed with their analysis after I explain this all over to them.
Have the car towed to the shop, they start it up, no lights on the dash and car runs smooth. They drive into the shop where it's gonna sit over night so the next morning they can compression test and leak down test it cold. They get 178 psi out of bank 2 cylinders and no signs of anything abnormal until they take it out and put a hard test drive to it and get the EPC light to come on and the miss between the lower RPM's. Now it's showing a cylinder misfire on #6. They pull the o2 sensor on bank 2 cat and inspect the inside of the catalytic converter and tell me they see deterioration and carbon build up. Not un-common at 105k i'm thinking. They tell me from everything they're seeing it points to that being the culprit and they say this should fix it. At this point I've been without this car for a month, countless hours and frustrations and speculations from 2 very reputable shops on what the cause "may" be and about a $1000 in diag time, parts and to have the injectors rebuilt. Now the repair shop says 11hrs of labor @ $120 an hour to drop the tranny because that has to come out to do the cats on this car apparently and $1000 per cat (my cost thru Audi is around $750 each and then whatever for hardware and gaskets). I don't cut corners so I'd do both at the same time if the tranny does in fact have to come down. Anyone know if this is in fact the case on replacing them? Anyone ever use the Magna Flow direct fit cats (part number 49135/49136)? I don't know how much longer I'm going to keep this so I don't wanna be into it a ton if at all possible. I can't afford to keep speculating either and just want this fixed so I'm hoping someone on here has either dealt with this or may have other suggestions. I think the valve spring issue has been ruled out. The cars runs well when driven conservatively other than crappy fuel economy. As soon as you push it it'll get that rough misfire feel until you hit 3k rpm's and smooths out but still doesn't have the flat out power that you get when you put your foot into it. Can a cat really give me this much grief and be the culprit?[confused]
Looking for any suggestions at this point
Dealership calls me and tells me that warranty company sent an inspector to come out and take an oil sample. Audi service advisor says they got codes P262900 (o2 sensor bank 2 sensor 1), Cyl 4,5,6, misfires and P049100/P049200 for the secondary air injection Banks 1&2 Insufficient Flow. They tell me that's something Audi will cover but they can't do it until cars running 100%. They clear the codes and go out and drive it and get it to act up like it was for me. They re-scan and get a cylinder 5 misfire. They swap coils and plugs around to see if it'll misfire on a different cylinder and it doesn't so they rule those issues out. They speculate at this point that it's a bad injector or a broken valve spring at that cylinder. They need the warranty company to authorize the next step. Turns out that my warranty after 100k goes to a "powertrain only" warranty and does not cover injectors. They are convinced that it's a broken valve spring and want to pull the valve cover. Warranty wants maintenance records. I had some in car and the rest at home. They only send what's in the car so of course my warranty company denies the claim due to "lack of maintenance". I spend the next week going round and round with them, sending them all of my records I have on everything I've done and finally get them to re-open the claim and let me get a second opinion once they realize this cars been more than maintained ahead of the normal intervals.
Since the injectors wouldn't be covered and a lot of the other shops I called to pick their brains, said this definitely sounded like an injector issue. I decide at this point I got nothing to lose. I'm pretty mechanically inclined and have been in the auto industry for nearly 22 years in parts and service so I figure this is something I can tackle. Take the car to a friends shop and we decide to start at square 1. Pull the plugs, inspect them (only 13k since I replaced them) no fuel saturation, all looked good so I swap plugs/coils from bank 2 to 1 and 1's to bank 2, clear codes and go out and run it again and cyl 5 is misfiring. Pull the supercharger off and intake manifolds and remove injectors. I separate #5's injector so when I take them into the shop whose going to test and rebuild and re-test can tell me if anything's abnormal with that one in particular. Get them back and nothing abnormal on any of them on the paper work. Replace the upper and lower manifold gaskets and plastic coolant bypass, injectors back in and button it up. Go out and still same issues[headbang]. At this point I proceed to have another shop who specializes in German cars and Audi's specifically proceed with their analysis after I explain this all over to them.
Have the car towed to the shop, they start it up, no lights on the dash and car runs smooth. They drive into the shop where it's gonna sit over night so the next morning they can compression test and leak down test it cold. They get 178 psi out of bank 2 cylinders and no signs of anything abnormal until they take it out and put a hard test drive to it and get the EPC light to come on and the miss between the lower RPM's. Now it's showing a cylinder misfire on #6. They pull the o2 sensor on bank 2 cat and inspect the inside of the catalytic converter and tell me they see deterioration and carbon build up. Not un-common at 105k i'm thinking. They tell me from everything they're seeing it points to that being the culprit and they say this should fix it. At this point I've been without this car for a month, countless hours and frustrations and speculations from 2 very reputable shops on what the cause "may" be and about a $1000 in diag time, parts and to have the injectors rebuilt. Now the repair shop says 11hrs of labor @ $120 an hour to drop the tranny because that has to come out to do the cats on this car apparently and $1000 per cat (my cost thru Audi is around $750 each and then whatever for hardware and gaskets). I don't cut corners so I'd do both at the same time if the tranny does in fact have to come down. Anyone know if this is in fact the case on replacing them? Anyone ever use the Magna Flow direct fit cats (part number 49135/49136)? I don't know how much longer I'm going to keep this so I don't wanna be into it a ton if at all possible. I can't afford to keep speculating either and just want this fixed so I'm hoping someone on here has either dealt with this or may have other suggestions. I think the valve spring issue has been ruled out. The cars runs well when driven conservatively other than crappy fuel economy. As soon as you push it it'll get that rough misfire feel until you hit 3k rpm's and smooths out but still doesn't have the flat out power that you get when you put your foot into it. Can a cat really give me this much grief and be the culprit?[confused]
Looking for any suggestions at this point