Rough idle: P1128 and P1136
The other day I noticed that when starting cold, the car would idle all over the place and misfire on all cylinders (sometimes going as low as 400 rpm before stalling out). I took it to my mechanic, and he replaced the fuel pump and two breather hoses. When I picked it up, it worked fine. Today, the CEL came on again while driving to work, and the codes are P1128 and P1136. I clear them, restart the car, and the idle is very rough (misfires are detected on all cylinders, but the CEL did not immediately come back on).
What could the problem possibly be at this point?
Both codes are lean run and generally a MAF or vac leak issue. Double check both. Has your mechanic used a VAG-COM on it? If not get one and start looking at what the sensors are telling the engine.
It's definitely running lean, the codes are P0300-0304, P1128, and P1136.





