blowing ignition fuse

[carpenter_jai]

I thought my fuel pump was shot, but now I'm not so sure. I know very little about electrical in cars per se, but I think I can apply my know-how from other dc stuff (the grounding is different correct?). So treat me bit like a kid please.

The ignition fuse blows when the key is turned to the on position. The car does crank if I turn past ignition. The engine vibrates more if I give throttle while starting, but absolutely no ignition of gas. I had thought that the fuel pump was in trouble, but I guess that if the ignition fuse goes, than the circuit that turns on the fuel pump, usually with the key in the on position, would not operate. Is this correct?

What are possible causes for the fuse to immediatly blow? Could the wiring insulation be deteriorating? Could it be a wire that has grounded or made contact with another wire?

Any tips for me to find the info I need from the Haynes Manual?

Thanks for any tips on electrical!

I will be out under my hood seeing if I can guess...

Jai

[carpenter_jai]

-And I wonder if the melted headlight connector may be getting worse and the cause of this problem. I have been meaning to redo that whole mess as my last attempt to clean up the common melting headlight connector in the fuse box as it was not exactly a roaring success. I think it was good for two months. That was over a year ago.

Jai

[Mike_Van]

I once had a short in a wire that was part of the FI circuit. It was causing the 20A fuse to blow anytime I tried to start it.

I expect such a wire-short in the IGN circuit could yield similar behavior.
Finding it will be a PITA, but the circuit diagram in the manual (Chilton's, I think) I left with my non-Geo-specialist mechanic allowed him to find my issue after a few hours. It was just a case of a wire with abraded insulation going to ground. It got abraded due to some PO (or PO's mechanic) attaching the wires to a clip that vibrated with the motor, rather than the original (factory) location.

And yes, Geo electrical troubleshooting really sucks.

[metroleum]

I have a 1997 lsi 4cyl auto had the exact same problem it turned out to be the fuse box in the engine compartment .The FI fuse (15a)terminals were not making good connection so I had to squeeze the female ends inside of the box together to make a tight fit.The fuse was arcing inside the terminals blowing the fuse immediately when I tried to start.Try replacing the fuse box in engine compartment very easy to replace these go bad often