My 1991 seville keeps blowing one of the two 7.5amp injector fuses. 10amp doesn't blow Does this mean
I have a bad injector? How do I find out which one? Or perhaps are there other than
half the injectors on this circuit which might be blowing the fuse?
Thanks
Potlatch

Have you inspected the wiring on the injectors to make sure none of the wires are smashed and grounding out on something or maybe frayed or cut?

If you want to invest a few fuses, you could try disconnecting the injectors one at a time, start the engine, and see if the fuse doesn't blow when a particular injector is disconnected. Then you could switch injectors around and see if the problem stays with the wiring or moves with the injector.

Seems like a lot of work, but electrical shorts can be difficult to track down. Start with a general inspection of all wiring in the engine compartment to see if it is something obvious before you start pulling injectors.

Thanks for your advice. It doesn't blow the 7.5 amp except after some driving. 200 miles this weekend with 10amp fuse and no problem; however I never really pushed it hard. And as I recall both times it blew was after a full-throttle event. The shop manual and wiring diagrams don't show anything on the
circuit than the 4 injectors. Anyone know if there'* more on that circuit? I mean it does run fine, altho
NOX emissions are very high, one injector is 0.2 ohns while others on that circuit are 1.0-1.3 ohms;
High NOX suggests lean, right? And I'd almost swear there'* a single cyl denotating on throttle tip-in..
Would all suggest one lean,dirty, failed injector? Of course, I can R&R the four suspects

I would be inclined to suspect the 1 injector that is different than all the rest. Lower ohms indicates closer to short I believe. Maybe switch that injector with one from the other side to see if the problem moves?

I agree. Switch the injector with the lower resistance to the other circuit and see if the problem follows the injector.

THANKS! EXCELLENT IDEA. i WILL SWITCH AND LET YOU KNOW