I've tried everything that everyone on this site has suggested to figure out what the issue with my MPG's could be and I'm still only getting 15-20 mpg in my '87 EFI. The only thing left is to hook the thing up to a code reader, so... I've decided to pick up a code reader and figure out if the car will tell me what the problem is but I'm not sure which one to buy? I'd appreciate anyone's input on which one they bought and why they like it. Also, where in the heck do you plug the thing in? I'm thinking on the cluster on the driver's side shock tower but I really don't know. Thanks!