I almost bought a new injector thinking I had a bad one, too. It turned out that it was really an air leak at the intake plenum. The air leak (loose hose) must have affected the #1 cylinder much more than the others (it was closest to #1) causing that cylinder to run so lean that it seemed like the injector had failed.
Here's a link to more about that issue:
embarrassing confesion
You could be right about a wiring issue. Oft times the small terminals inside the Bosch connectors loose their spring tension or get bent or move out of position. Look real close - make sure that the male spade isn't bent over (thus failing to make a connection) and that the female terminal grips tightly (you can use a tiny screwdriver - a jeweler's screwdriver - to re-bend the connectors to ensure a tight grip) . Also make sure that neither terminal is loose inside the connector. Gently tug on the wire harness and see if the terminal inside the connector moves (it shouldn't).
The connectors you mention - one 'silver' & black - might it actually be
grey & black? I think you may be looking at the flywheel sensor connections. There is info in the
Spider L-jetronic diagnosis page about them and how to test them.
Make sure you understand what's involved. Doing it wrong could fry your car's ECU (computer).
Linear Mode
