Sporadic no start

[Walter F.]

I have a 1984 which I have owned for 10 years. When I got the car it had a MSD cap, rotor, and coil. I soon found out from time to time ( about every 500 to 1,000 miles ) I would get a no start condition. The rotor would have black lines on it telling me the spark was arching. I changed the cap, and rotor to stock and continued to have the same problem. I changed the coil to stock and was able to get almost 1500 miles before the same situation happened again. I only drive this car about 1,000 mile a year. But things seem to be getting worse now. Last week I had the same problem, put on a new rotor car started right up and 50 miles later same thing. In all the years I have had this car the engine has never missed, performance is excellent, only this no start condition with rotor showing black lines on top after a no start condition. Put on a new rotor and you used to be good for 500 miles. I been told to check the voltage to the coil. But the coil has less then 1500 miles on it. Any suggestions.

[Edward J.]

Re: Sporadic no start

Walter are you seeing fuel from the throttle body injectors when turning the engine over, or is it a no spark condition? I HAVE NEVER SEEN a cap and rotor go bad this many times re-guard less of what coil you use.

[Walter F.]

Re: Sporadic no start

I smelled fuel, I never thought to look to see if the TB were pumping. I heard the pump winning so I know it was working. Last night when I got stuck at the store I tried several times with no success, and had to call my brother to bring a new rotor. I smelled fuel for about 5 minutes after the no start condition. As soon as I replaced the rotor after sitting 40 minutes waiting for my brother, the car started right up and drove fine. The new rotor with less then 50 miles on it had a black line across the top.

[Edward J.]

Re: Sporadic no start

Walter, I have no logic reason for the failure of so many rotors, but I would look for a Nos cap and rotor on Ebay. its worth a try. I myself have used many after market caps and rotors without failure, ( Accel, Mallory,Napa etc.). being in the automotive trade there seems to be many auto parts produced in china that are poor quality. I might also say take one of your old caps and make a cut away so you can see if there is anything that you may not be able to see once the cap is installed.( check the gap between carbon button on coil tower and rotor tang)

[Walter F.]

Re: Sporadic no start

Last night I took apart the cap rotor and coil. The spring was in place with the carbon button , but when I pressed on the button after I put it back together I did not get any movement from underside of the cap button. Is that button suppose to move ? I did not press it with a lot of force, just with my finger tip. If the button is suppose to move, about how much force is required ?

[Edward J.]

Re: Sporadic no start

Do you have the spring and button installed first or the rubber then the button? you should feel contact with the carbon button, is the carbon button broke?

[Walter F.]

Re: Sporadic no start

Button, spring, and rubber in that order under coil.. Should the button move when I press it from inside the cap. How much force should it take to move the button ?

[Mark E.]

Re: Sporadic no start

It's been a few years since I worked an HEI, but I recall being able the depress the cap's rotor "button" a mm or two with little pressure.

It's possible the carbon trail on the rotor is caused by excessive secondary voltage. Or maybe a mismatched cap and rotor. Try a fresh OEM cap, rotor, coil set.

[Walter F.]

Re: Sporadic no start

I am having second thoughts now about the cap and rotor. I took the rotor that went bad on friday night after only driving about 50 miles with the replacement rotor and put that same rotor back in this afternoon. This is the same rotor that failed Friday night. The car started right up. So now I am beginning to think the smell I smelt on Friday night may not have been gas. It almost smelt like carbon exhaust fumes. Since this problem is sporadic and may not happen again for 500 miles. When it does happen, and it will, my first place to check this time, is going to be for fuel and spark. Again the car has never missed in all the years I have driven it. This is why i am not sure it is a problem with the distributor. It only has this no start issue. I have always replaced the rotor and it has always started. I have been doing this for the past 6 years that this has been going on. I am beginning to think the time span has something to do with the car correcting itself. It usually takes me about an hour to go buy and replace the rotor and put it on. I am beginning to think since the car is now running with the rotor that I thought failed friday night, that if I let the car sit, should I get a no start condition, the problem may corrects itself. I suppose that will open up a whole new bag of worms.

[Mark E.]

Re: Sporadic no start

When I was six years old, my mom relied on a well worn, poorly maintained '57 Olds 98 to make her 60 mile round trip commute to work.

When it wouldn't start in the morning (two or three times a week), mom would continue to crank it while pumping the gas. I remember smelling gas. The only way I knew to help was ask mom to stop for a few minutes while I checked and filled the radiator. When it started 10 minutes later, I was convinced low water caused the starting problem.