I have an 01 Suburban that gives me a P0300 OBDII code and 2 other codes, I erased them but they were for... Bank 1 and Bank 2 Sensor 2 on both banks. The exhaust smells bad but not like rotten eggs. There is no smoke out of the tail pipe. I have replaced both cats and all 4 O2 sensors about 2 weeks ago. I checked my plug wires and fuses.

I have a couple of questions....

1. I noticed someone had said that there might be trash in the fuel rails, how would I check this out??
2. How would I isolate the misfired cylinders??
3. Could those O2 sensor have gone bad that quick??
4. Is Sensor 2 the the sensor after the cat??
5. What causing that nasty smell out of my tail pipe?

I know it's alot to throw out there but I'm lost..
I need to trade this thing in for one of those new Tahoes, nice....
Any help would be greatly appreciated.

Thanks
Art

My Guess would be fuel pressure regulator.....you didnt give much to go on but the last few p0300's i have seen on these trucks were regulators