Platinum5

Hi I have a 09 A4 2.0 TFSI CAEB, car was running great and then all of a sudden now I have a real rough idle and misfires. Could not find any intake leaks. Here are the codes maybe one of you have had this problem, I just replaced the pcv valve and am still having problems.

4515-P1950 Radiator Fan (V7) Movement Restricted Jammed - Mechanical Failure

5646-P2279 Intake Air System Leak _

2811-P0171 Fuel Trim; Bank 1: System Too Lean - Open Circuit _

5658-P119A Fuel Pressure Sensor - G247 - Malfunction _

4007-P0507 Idle Control System RPM: Higher Than Expected - Short To Ground


Once I replaced the pcv valve these codes came up right away.


5646-P2279 Intake Air System Leak _

4010-P0506 Idle Control System: RPM Lower Than Expected - Open or Short to Plus

4054-P0301 Cylinder 1: Misfire Detected - Short to Plus _

4060-P0303 Cylinder 3: Misfire Detected- Electrical Fault in Circuit _

4063-P0304 Cylinder 4: Misfire Detected - Cannot Be Tested at this time

4057-P0302 Cylinder 2: Misfire Detected- Open or Short To Ground

4051-P0300 Random Multiple Cylinder Misfire Detected - Mechanical Failure


Does anyone have any tips or know what I should look for?

Thank you in advance.

motoguy128

Maybe it's not the PCV. Maybe another vacuum line after the throttle body is leaking. Maybe throttle servo body itself? Fuel pressure sensor malfunction???? Seems like more systemic electrical issue. Maybe a battery ground cable is loose? Or bad connector on the engine ground. blown fuse?

Donald Kaufman

Check for oil leaks at front of trans. Likely a rear main seal due to faulty breather. Replace both. Rear mains can also be faulty inversely without leaking oil. Special tools required to install.

Allan Francis

It might need a vacum pump mine did the same thing I would start it in the morning and it would missfire and run like a bag of crap but once it warmed up a bit it was fine turned out the seals were going in my vacum pump

Allan Francis

The 2.0 have a unique way of pressurizing the crankcase there could be an external pressure leak. Example if you pull the dipstick out while it's running itll missfire and run terribly but if you simply put your finger over the hole itll run fine again. So it could be as simple as the o ring on your dipstick is dead.