Ignition Problems

[CheeseRules01!]

My car seems to have a pretty bad ignition issue. It has a random misfire while it's running that sometimes is bad enough to kill the car. Every time I let it idle it wants to die, especially when I put it in gear. I think it might be the ignition coil or the ignition switch. Any Ideas?

 

[67Dart273]

My car

Well the first thing we need to guess is just what IS "my car?"

Next is what exactly you are running for an ignition system?

And probably the last thing is what have you noticed/ checked/ seen / or heard that leads you to believe it's the coil or switch?

These questions.......and many more...........will be..................

 

[halifaxhops]

 

[70aarcuda]

and where is the timing set?

 

[halifaxhops]

Seriously it can be a ton of issues, carb, ignition, timing chain, cam, ring, really have to help us narrow it down. First of all what is it? engine, ignition, carb?

 

[Murray]

Sounds like you have multiple issues. Ignition switch, cam, timing chain, rings- these are not among them. Keep it simple, you have ignition and/or fuel problems. Rule #1, electrical must be good before we can diagnose fuel. To start, what condition is the ignition in? Have the wires been checked? Have you checked the compression?

 

[BillGrissom]

The good part is the problem sounds like you can easily reproduce it. Get a can of starter fluid (Walmart, etc) and spray shots down the carburetor throat. If it idles much smoother, your "electrical problem" is actually "not enough fuel at idle", i.e. "lean". If you have a Holley 1920 carburetor, I wouldn't be surprised (please tell us). Spark misfire is most common at WOT and low speed, like when accelerating on a freeway on-ramp.

 

[Murray]

The "old school" way is to just put your hand over a running engine's air horn, partially blocking the air supply. This enriches the mixture. If engine smoothes out or speeds up, that tells you that your mixture is too lean. In that case, you probably have a carb problem or a vacuum leak.