I've got a working MPGuino, and when I uploaded the OBDuino rev 32 code I got this exact same thing:
(Except that you have the LCD upside down in this pic
Gotta be something in the initialization code. Did you see that dcb updated his initialization code w/ Yoshi's suggestion for his v0.67? Maybe that's worth a shot. I'll read through the code later to see if anything stands out.
This definitely doesn't have to do with the 511ohm vs 510ohm resistor. Where do you see that its 511ohms? Did you measure that? Because the gold stripe on the resistor indicates 5% tolerance (+/- 25ohms), so you most likely have a 510ohm resistor that's actually quite w/in spec. 510ohm should be green-brown-brown (
51 * 10^
1).
The difference between a 2n3904 and 2n3906, however, is a big one. The 3904 is an NPN transistor, and the 3906 is PNP. These run in reverse polarity to eachother, so I would change that out for the correct one.