I believe that one of my two ingntion coils is bad. The car starts easily and seems to be hitting on 4 of the 8 cylinders. There are two coils on the car, one on the side of the engine and one on the top. Each coil fires 4 cylinders.

The coil wire going to the cylinders is accessable on the coil attached the side of the engine. If I disconnect the visible coil wire going to the spark plugs and attempt to start the car will I cause any electrical damage to the system?

If the car starts with the left coil disconnected, I will know that it is the problem. Otherwise I will have to disassemble the moldings on the engine to get to the spark plugs to see if they fire.

The check engine light is not on, but the car has gone from running perfectly to running horribly after sitting overnight in the garage. The RPM gage also pegs on zero if the engine exceeds 850 RPM and resumes its normal function when at 550 idle. The cold start mechanism that normally revs the engine to 1100 has also ceased to function. The threads from the Forum suggest that one of the two ignition coils is bad.

Any advice on fixing this problem and testing the coils is most welcome.

Toughguy48

 

I pulled the plug wire cover off of the passenger side. pulled one plug at a time. found that two of the four made no difference. swapped coils, and the two now sparked, but the other two quit. easy, safe, and no worries of frying a coil (supposedly possible, didn't wanna risk it.

 

i had the same issue with my 400.. you will not cause any damage by unplugging on of the coils at a time to diagnose your problem.

 

this definitely works and is safe to test. I had to do this with my 400 as well. but be warned, they will shock the crap out of you so wear some thick leather gloves. good luck. Also with mine I thought it was a coil issue but turned out to be distributor. But testing at the coils and plugs should help determining which it is.