modern engines. It's more like replace that bad sending/receiving unit with a new one, after the computer plugged into the data port tells you which one is bad. So there is less to tinker with on the engine itself. Not like rotating the distributor cap to adjust timing or turning screws on a carburetor to adjust idle and a/f ratios. So the mfrs. put this extra layer of separation between the user and the mechanicals, the automobile becomes more appliance like. I think it is part of the reason the muscle cars from the '50s , '60s and early '70s are doing so well at the auctions, you can see and tinker with the mechanics without a degree in computer/electrical engineering.
