Ignition switch failure can be notoriously intermittent. The problem is the switch contacts are worn and burnt. Sometimes make connection and other times no. Switch is about $30-$50, depending on source. Check ebay and rockauto for good deals.

good luck

 

Thanks again for walking me thru this. My neck cant take anymore upside down afternoons testing harnesses!!

 

Can anybody tell me why I would blow a 50 amp fuse, IGN/SW as I first put my key in to test my brand new electrical ignition switch? Looked like it sparked out of the main harness that plugs in the switch. No places open to get one of those so I'm dead in the water tonight. I had neg batt off until install was complete and plugged everything in. Baffling!!

 

Sounds like maybe a loose connection id start lookin for broken loose or chaffed /pinched wires

 

The 50A fuse is on the ignition switch circuit. I would suspect either damaged ignition harness wiring, damaged connector pins when you mated the switch to plug, or defective switch. I would remove and test the switch contacts looking for a permanent short and inspect harness and connector carefully.

Looking at wiring diagram check under dash fuse box for blown fuses. It's unlikely since they would have failed first and protected the 50A fuse, further indicating the problem is in the ignition switch harness, connector, or switch assy.

good luck

 

Ok, new 50 amp fuse installed. I think my problem might have been that I tested the switch without having tightened down the bolts all the way. I'm having to reuse the old shear bolts and wanted to test switch in place but not tightened down. Thinking tightening to steering column was a ground for the switch because after full reinstallation my new 50 did not blow but I have no dash light on position II but it will turn over on Start position. Think I blew out my new switch?

 

Hard to say. I reused shear bolts also. It doesn't need to be very tight. I used cold chisel to tighten that was used for removal. It's possible you got a defective switch.

Ignition switch doesn't require a ground (only switches power). Ground is on the component that's powered; starter, fuel pump, etc.

If a ignition switch contact shorted to ground, that would blow the 50A fuse.

good luck

 

think I got a bad switch, first one had no plastic cover over the copper/brass leads on the side. Every switch I've seen has a cover for those including my new one I just swapped at Advance. Puttin it on now.

 

New relay, new switch, still no power to #7 on relay and still solid check engine light w no codes. Anybody have ideas?

 

Have you checked the inputs to the relay?

There is a link to a manual you can dowload in the Common DIY Threads. It will walk you thru testing the inputs (~section 11- page 96)