I have a 1986 firebird 305 and it has the folloing problems.
What I have done.
New plugs, cap rotor, wires. 45lb fuel whiel running or not.Checked timming chain.
Runs but misses some time it will run fine for a few seconds then start missing back fire and die or sounds like it drops cylinders.When it does sound like it is running on all cylinders it is running rich. I have to turn the distridutor advanced to get it to start.
Richard

 

Any error codes? If it is indeed running rich, you should be getting a code for that. Have you verified that all cylinders are getting spark? Hold old/how many miles on the injectors?

 

how did you check the timing chain
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As for the timeing I checked the crank to distributoer relatinn and sack in chain.
I did do the jumper wire thing to retrive codes and the only one that came up was a # 12. The book said that means evey thing is OK.
Richard

 

Yes, code 12 is normal. It means no ignition pulses from the distributor, and its from when you turn the key forward before starting the car. I would recommend having the ignition module checked, Autozone can test it. It's located under the distributor cap, it's the part with all the wires going to it. I've seen them act up when they get hot, sort of like you're describing.

 

That sounds like a excilent Idea we only have a Knects here so i will ask them if they can do that. If not I ges I can buy a new one.
R/T

 

What does the spark controler module do?

 

Anyone got the replacement part# for the IGN contol Modual?
I looked on Ebay and can not find any with 5 small pins and two large ones for this year?

 

I just installed a new IGN Modual and it runs fine, I want to say a BIG THANKS to all that helped me on the delima.
Richard

 

Glad to hear that fixed it. Sort of late now, but the ignition module is what controls the timing advance. The ECM tells the ignition module how much advance it wants, and the ignition module makes it happen. Sort of the electronic equivalent of the vacuum advance on an old style distributor.