car only starts sometimes no spark

[coreydmc]

I am at a loss. Some days the car starts fine, others it wont start at all. I know it is not a fuel problem because i smell plenty of gas and hear the fuel components working. I checked the inertia switch and that is fine. When this first started happening i replaced the coil with a OEM bosch one from DMCH. My wires and dist cap are not that old. My fuses are also good. What else should I check for? My car is sitting in my driveway cause i cant get it started to pull in garage. I dont want to keep trying to start it because the cyl's are just filling up with fuel.

[David T]

Check the connections on the white ballast resistor on the firewall in front of the motor. Another possibility is a bad impulse coil.
David Teitelbaum

[jmettee]

RPM Relay? If there's no spark, other than the coil being bad or a disconnect in the wiring, the RPMs relay is the trigger for the ignition system. When they go bad, they have flakey soldiers that sometimes make connection & sometimes do not.

Got a second one to try out?

[opethmike]

As David said, check and clean up the ballast resistor connections. Also, check and clean up the connections on the coil itself.

[Bitsyncmaster]

Is your starting problem only with a warm engine?

Lots of things can cause starting problems. The more data you provide will help us narrow down the problem.

[coreydmc]

starting is only an issue when cold. ill clean the ballasts. where is the other parts located i should check?

[coreydmc]

is the impulse coil in the dist cap? ill also order another rpm relay. Should I get it from DMCH?

[coreydmc]

ok i checked the ohms on the impact coil. i unplugged the terminal wire going into the firewall and tested the coil side of the wire. i get 541 ohms. if it should be 600 or higher is this my problem. I dont think it is the rpm relay because i smell gas and hear fuel pump working. i also checked the inertia switch and fuses.

[Bitsyncmaster]

Does the engine fire at all when you have the problem?

[coreydmc]

when i turn the key and hold it for like 5 or 10 seconds the car will on RARE occasion sound like it wants to start. like it is getting a spark to ignite gas but then goes away. But this doesnt happen all the time. I also smell a lot of gas from the engine