Ok i will give as much info as possible, i have a 305 carb 83 camaro.
About 3 days ago i decided to change out the distributor cap and rotor from stock to an msd brand. installed it and nothing happened replaced the ignition coil and still nothing, replaced the ignition control module and it fired right up... But... now it will not idle correctly (yes even adjusting the fast idle speed didn't work) and also when i push the throttle it starts backfiring like crazy from the carb and usually dies out after a few backfires. What is making me wonder is that before we changed it over to msd it was running perfectly fine. Just wanted to swap it since it was old and have never been changed before. Also if this helps i put the old cap and rotor back on but used the msd bushing (as our stock bushing crumbled) and it still backfires. could this possibly be a fuse box problem? i dont really know what or where to look for this problem since the plugs were changed about a month ago... The plugs are all numbered too so we couldn't have crossed a plug wire either. I'm starting to believe that my Cam hates me...

 

Did you verify correct firing order and timing after setting the rotor?

 

did not but I did not adjust the timing at all on it. would that be my problem? (sorry for the dumb questions as this is my first time messing with a distributor cap and rotor)

 

Yes. The rotor turns inside the cap and the striker aligns with the terminal in the cap which the spark plug attaches too. If you didn't line it up again well you're #1 plug wire could be anything. Meaning your timing is off.

 

Okay I am understanding what you are saying so far now here is another question, how would i set the timing back to normal. And idk if this is right or not but my father said that he didnt think itd be the timing since it starts up really easy. But after the problems i have been having i am definitely not ruling it out.

 

Mark the balancer with something that will show up easily on my OEM one I would use a white marker/white out etc in the groove of the balancer so it will reflect light better. Hookup a timing light to the battery, pickup to #1 wire, and shoot the timing with the motor running pointed at the balancer while aiming at your timing tab on the lower driverside. Depending on your timing light it might be as easy as turning a dial or you might have to press a button up or down. That'll give you an idea.

I've seen them way off 45*+ degrees and still start but cough and die as soon as it tries to add more timing. I actually thought my Snap-On light was bad so I bought a cheap $30 AutoZone one just to be given the same measurements.

Looked up a quick site for you: http://www.carcraft.com/howto/ccrp_0...tor/index.html

If you look at the 3rd image it says "Once you've marked the position of the distributor in relation to the block, you can pop the cap and mark the location of the rotor in relation to the housing. This is important because moving the rotor in relation to the housing changes timing and, if it is moved far enough, can fire the wrong cylinder in the firing order. Then it goes bang and your dog runs away and your friends laugh." I believe that's exactly what you are experiencing.

 

okay i will definitely check that out, i hope that this is the problem since i have a solution for it. Thank you so much for clearing this up as many others have said changing the rotor and cap wouldn't affect the timing. i will order a timing light and jump on that asap.

 

You can probably get one from your local Autozone or etc. They are fairly cheap for the Actron and those types. They might even have a rent-a-tool one. There are plenty of good articles on setting the timing. So I frankly don't care to open that can of worms here. Like I said though just shooting it will give you a good idea of where you're sitting at.

 

If all you changed was the dist cap and the rotor, and not the entire distruibutor, the timing did not change any. You probably got a plug wire connected to the distributor incorrectly. Did you remove any wires at all?

 

Maybe I am wrong. I was just originally thinking my cap can be installed two different ways.

 

Neither the cap nor the rotor can go on 'wrong' as they are both keyed to the distributor body.
The first thing that comes to mind is you mixed up the firing order with your wire re+re.

Click on my pic to see the firing order

 

i did take the plug wires off but put them all back on correctly since it came with a top cap that fits around the plugs that are numbered. the plugs were changed about a month ago also but like i said the things that i changed on it was the distributor cap, rotor, coil, and ignition control module. somehow whenever i replaced the cap and rotor the ignition control module blew. i wouldn't think that the pickup coil could be going bad. but that isn't a ruled out option since i have hardly any.

 

Yeah, the cap can be installed 2 different ways - but as long as the plug wires were put back on the right terminals, there shouldn't be an issue.

Now if the distributor itself was replaced, then it's necessary to find TDC on compression stroke.

 

that's what is stomping me at the moment. I mean I cant really think of anything else that could have went wrong for setting up like 3 days. Do you guys think that i should use the other striker/bushing? the msd pack came with two of them a black one and a bronze looking one, right now it is running the black one. idk how this could affect anything but maybe it needs that one for some odd reason. I'm just not having any luck with this car haha.

 

That's the firing order for YOUR car, not necessarily his, or any others.

I mean ... the order as in 1, 8, 4, 3, 6, 5, 7, 2 - that is the same as any and all SBC motors.

But the location on the cap - which terminal is #1, is not necessarily the same on every car. The #1 terminal can be any of the terminals, but it HAS to be the one that the rotor button points to when you are at TDC #1 pistion on compression stroke.

Please don't tell folks that the terminal at the 5oclock postion on the distributor cap is the #1 plug wire, because it doesn't have to be, and can be any of the terminals on the cap - it just all depends where the rotor points when the #1 cylinder is at TDC on compression stroke.

coty - in all honesty, at this point, the only way for you to know for sure, is to get #1 piston on TDC compression stroke, then look and see where the rotor points ... making sure that corresponding wire on the cap goes to #1 plug, and then follow the firing order around and verify the other 7 wires are running to the correct plugs.

Can you link us exactly what it is you bought and installed? Because personally I have a hard time thinking that all you replaced was the distributor cap - because I see no distributor caps by themselves available by MSD for a factory distributor.

 

http://shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_Distributor-Cap-and-Rotor---Red-MSD-Ignition_6900012-P_192_R|GRPTUNEAMS_976638321____

if im not mistaking it, i think it was this one that i bought.
But this cant be the only problem that im having since i put the older cap and rotor back on thinking that the new cap and rotor were somehow messed up, and it did the same thing. lol its really confusing the heck out of me at this point. but the only thing that might be different from these things are that the bushing/striker are different since my factory (1983) striker crumbled while lifting up the cap. yes it has never been changed before... The msd rotor and cap kit came with two of them, a low resistance bushing and the stock bushing, however it said in the information manual that the low resistance one is only needed for higher performance vehicles which i have a stock 305 so that wouldn't relate to me. Or at least i wouldn't think so at least.

 

OK - sorry to doubt - I justy couldn't find a seperate cap from MSD - I was looking at Summit.

You must have a plug wire run wrong - like I said, just get TDC #1 compressionstroke, and re-run all the wires from scratch. Takes like 10 minutes to do.

Pull #1 plug.
Put finger in hole.
Have someone rotate engine (bump starter or turn by hand) until you feel air pressure on your finger. Then, line up the balancer mark with ZERO on the timing tab.
Replace #1 plug.
Remove dist cap - wherever rotor points, THAT terminal on the cap HAS to have the #1 plug wire on it.
Then follow firing order clockwise and redo the rest of the plug wires to the right plugs.
Done.

I could have almost did it in the time it took me to type this.

 

lol ok thanks a bunch for the full explanation as i wouldn't have known how to do that, im just still really lost on how it could do this over night since i labeled all the wires of how the came out of. im not doubting that this cant be the reason but am just lost because i know for sure they were all put on correctly (well the same way that they came off at least). I will go check that when my wife gets home. also heres a quick question that might also be doubting me, since i had replaced the ignition control module i am about 80% sure i got the wiring right on it since two wires came unplugged while in the process of changing it. would it be possible if those two wires were switched to the incorrect terminals that it would still start and run the way it is? Or would it just never start and possibly short something out? i thought that this may be another logical question (since my knowledge of distributors are limited)