hey, this is my first post im really new so bare with me. I have been searching through the posts for the last hour and haven't found anything like my problem but then im not good at finding things. I have an 85 camaro that was a 305 tuned port injected, last year i put a carburated 350 in it.... everything on it is brand new aftermarket, or has been rebuild. The problem started after i had swapped camshafts for the 4th time in like 4 weeks, i have had this cam in before with no problems, this is what happend, after i swapped cams, i fired it up and heard a "BANG!" and i could smell that electrical burning smell, then it wouldn't start at all. I replaced the module in the distributor (Proform HEI dist), and it ran, runs fine at idle, but when you get on the gas in every gear after 1st, (im guessing first gear rev's too fast to notice it) the spark starts to cut out and the car stops pulling, just misfiring like crazy. Im thinking that the module wasn't the only thing that got fried, maybe some wires that connect the ignition to the module and coil or whatever that got messed up and that burning smell was the coating on the wires that got melted off? im not sure. Any ideas? if anybody's heard of something like this before i'd appreciate the imput. thanks guys.

 

What is your timing at around 3500 RPM? Sounds like your advance isn't set right, or something along that line.

 

The rotor hit the cap, and now the contact tip is bent off to the side

 

well i've checked the timing and it looks to be around 30 or so i don't actually have a full timing strip, just the peice that goes to 20 degrees advance but it looks right. but the car runs fine at idle and in first gear only cuts out when i get on it in second gear and third and fourth gear
i'll buy a proper timing tape for it so i can make sure the timing is good at 3500 but i won't be near my car until 3 days from now, i'll play around with it some more and let you know how it goes, thanks guys.

 

have you popped the cap off and looked at the rotor?

 

yeah, dude i've had it right apart, in peices and put it back together like 10 times, i even tried a completely different distributor out of my friends engine and it works fine in his but not in mine, so it's not the distributor. good point though.

 

OK... one other simple thing.... have you tried disconnecting the tach lead?

 

what would that do?

 

The module works by grounding the low side of the primary winding of the coil (the high side goes to battery), and causing current to flow for a time; then at the moment that spark is to occur, it shuts off the current flow. The magnetic field in the coil collapses. The energy stored in the magnetic field in the coil has to go somewhere; it appears as a spike of voltage across the secondary winding, which is connected by means of a switch (cap & rotor) to the spark lugs.

The low side of the coil is also brought out as the Tach lead. A bad tach, or tach filter, can allpow current to continue to flow, and drastically reduce or even disable the system's ability to produce sparks.

Also, is there popping in the exhaust while this is going on? If the dist isn't firing but fuel is being fed, then the next cyl that does fire, will ignite the fuel load that will be dumped into th eexhaust. If it's not doing that, you probably have a fuel delivery problem, not a spark problem at all.

In no case whatsoever will timing, by itself, cause the symptoms you describe. I would twiddle the distributor back where it belongs, tighten the bolt, leave it alone, and start doing some real troubleshooting.

 

i didn't know that....if a surge can wreck a tach or tach filter then that might be what happened, cause whatever is causing it is related to the explosion i had it worked fine before that. something is defenately blown. i'll just have to eliminate the possibilities systematically i guess. i'll try the tach first thanks man.

 

Explosion?

Ya know, it's alot easier to get help that goes straight to the point, if you tell us what's really going on.

"Uh doc, there's no feeling in my toes" "Have you tried massage? blah blah blah" "Yeah, nothing has helped" "How long have you had this problem?" "Since I stepped on a land mine in Nam back in 71 and blew my leg off at the hip"

Know what I mean?

 

I thought that the "BANG" part covered it..... what did you think i ment? I guess it's not really an explosion... no fire ***** or anything, just bang, sizling and smell.