Hello everyone. I am interested in purchasing a code reader, and I do not know where to start. Based on previous posts here, I am fairly certain that all cars built after 1996 are OBDII compatible.

1. Would an OBDII reader from any manufacturer (Actron, Autozone, Pep Boys) be the right choice for my vehicles (Mine-1998 E300, 1999 E320 4-M, 2002 Cadillac Escalade; Grandfather's-1995 E320, 2001 E320, 2000 Oldsmobile Bravada)?
2. In some other threads, I read about the very expensive Mercedes Star tool. If Mercedes requires this special code reader, what kind of codes can the OBDII tell me for a Mercedes model (MAF?, O2 Sensor?)?
3. Finally, is the 1995 E320 OBDII compatible even though it was built before 1996, and...
4. will the same code reader work appropriately for both Mercedes and General Motors models?

Sorry for the super-long post and many questions!!!



Happy Holidays!

Try and see if you can find one that will diplay live data in addition to codes. I just bought a used Matco OBD II scanner off ebay, and it gives a wealth of live info. I used it to diagnose a bad maf sensor in my '97 Cadillac Eldorado, using the live data stream. It was flowing too few grams per second and leaning out the mixture, causing terrible pinging. The dealer wanted $100 just to begin diagnosis.

It was a big step for me, as I grew up tuning cars with a vacuum gauge and a dwell meter. This was the first time I fixed a car without having to wash my hands. It took ten minutes to change the maf sensor and air filter.

Btw, the first thing that parts guy at the dealer asked was if I was using a K and N filter, he said the oil contaminates the maf sensor.