I need some help!!

When I am driving my Tachometer occasionally goes crazy and the engine wants to stop.. at one point I believe their was a misfire or something because when driving I heard a small explosion with brown smoke coming out the exhaust. the car didn't turn off but it felt it wanted to... when I pulled over I check my coil for electrical reading... with my check light and vehicle on I got a light on with the positive terminal .. when I checked the negative lead in coil I also got a light on,, is this normal to get I light on with the negative terminal.. I checked my vehicle again right now and when I put the light on the negative terminal the car turned off! can someone help me trouble shoot this.. thanks

What year is your car? If it is a 75-76 and the coil is mounted on the tin, the coil can rotate in its mount and short out on the tin. For sure though, something is shorting out your ignition system.

I have a 73 1.8, and the coil is mounted on the tin.... do you think the coil is bad with this... or how can I solve this problem...

Make sure your coil hasn't rotated in the mount so the electrical connectors are touching the tin.

Swap in a different coil

Pull your cap and look at your points

Call your towing insurance

Have a beer or two...

I have electronic ignition...

So to be sure... their should be no light on when I put in negative of coil....

I would disconnect the tach lead (black with purple) and drive the car with it disconnected. If the problem goes away the tach is starting to go bad.

Thanks Dr. 914 I will do that..... I am going outside right now to check my current flow and see how the car is running...
Cant believe I got some advise from the DR.!!

It could also be that your points-replacement (Pertronix?) is starting to go bad. If unplugging the tach wire doesn't cure it, try swapping points back in as a diagnostic measure.

--DD

Thanks guys for your feedback... I removed the tach lead from the coil,, problem continued... I replaced the coil with one I had laying around, the problem seems to be fixed, I drove the car around and it felt great.. the real test will be tomorrow when I drive to work... will see what happens...

Bad coil is rare but not unheard of... Glad you got it fixed.

Thanks everyone for all the advise... my 914 drove beautifully to work today!! this is definetly a great resource!