My engine light started flashing today as I was driving. The RPM's go down to 1,000, then the engine begins to shake rather violently. There is a smell coming from the exhaust that smells like a match burning. I'm guessing it's either catalytic converters or spark plugs, but if anyone could second that or tell me otherwise, it would be greatly appreciated.

 

At the shop. It was a bad coil. $170 to replace.

 

I have replaced all fuel injectors when one failed at 138k, trying to get an idea on cop failure . I have changed boots and spark plugs twice now . Maybe I should buy some spares now and leave them in truck , it would only take a few minutes to change one cop .Thats why I changed all fuel injectors some people had spent 1k changing them one at a time on the road in an emergency desperate fix.

 

flashing cel means a misfire, so a bad coil sounds right

 

How will you know which one is causing the trouble?