What is your question?
1999 jetta 2.0 AEG MKIV stalls, bucks, stumbles and runs great, in that order. When I come to a stop it is likely to stahl and is doing so more and more. But then it starts right back up and runs perfect for maybe a second maybe for the rest of the day. The part that is confusing to me is the ignition timing is usually around 25 to 30 btdc while cruzing and then it jumps to 4 to 10 atdc and I have no idea why. I am car savy and know my way under the hood but this one has got me stumped. The only DTC is for the catalytic converter (which I already replaced) and it won't clear for more than one day. VW dealer says a universal cat. is going to trigger the code, I wonder if it has more to do with the exhaust that I made and where the tip of the downstream O2 sensor sits in the diameter of the pipe. I am running a stock exhaust, no mods, for all intents and purposes the car is all stock. New MAF, Throttle body, and Cat. converter. I can monitor the timing with both an OBD2 code scanner with live data and I bought a cable to hook up to my PC and I watch the timing that way. If you can offer any suggestions then please........I am all ears and would greatly appreciate it.
