The service manuals don't explain how the fuel injection system works. Here's a book that does. It was recommended to me by two other list members. It covers all the different types of Bosch injections, including CIS, L-Jetronic and LH-Jetonic.
"Bosch Fuel Injection & Engine Management" by Charles O Probst
$24 + $4 shipping from amazon.com
Very detailed theory of operation explanations, and lots of pictures and figures, too.
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