carb'd ls1 ignition problem
 

my carb'd ls1 with a msd 6010 box is'nt firing on #7 cylinder and i've switched plugs,plug wire and even put another set of coil packs on it with no luck...the problem started after i loaned my cam sensor to a friend in need,could this cause the problem?? does the cam sensor need to go in a certain way or does it sync itself? i'm kinda clueless on this...any help would be appreciated...thanks billy

have you verified that the coil hasn't died ?

I'm interested in finding out about the cam sensor as well. I purchased a rebuilt motor with the cam sensor mounted but the bolt just hand tightened. I just torqued it down but haven't fired it yet.

I changed coils from another motor and its still not firing...

can only suggest a few things to check... hope it helps..

have you check the pig tails and connectors on the coil and harness ?
is the #7 plug wet or dry ?
Have you used a scanner to pull codes and real time monitoring ?

Good Luck

BC

According to MSD if the cam sensor is completely disconnected then the box has a 50-50 chance of starting up properly. I can tell you first hand the box will run the car with no cam sensor at all. So the fact the other 7 cylinders are firing properly tells me it is probably not the cam sensor.

You can try firing just that coil by triggering it with a 9V battery.

Whats the trick with the 9 volt battery?

Subscribed

There are only 4 wires going to each coil pack: 12V power and a 5V trigger signal from the computer. If you hook the 12V up like it is suppose to be the coil should fire every time you touch a 9V battery across the trigger wires. That will at least tell you if the coil pack is good. If it is, then you need to find out why there is no signal from the computer. You can do the same thing by just swapping coils around, but this is another way of testing them individually.

http://pictureposter.audiworld.com/1..._schematic.jpg

Sounds like a harness issue. After checking that pins haven't backed out, I'd probe the MSD harness for #7 cylinder. A VOM between pins A & D should show 12v with the key on. Observing a VOM between pins A & C while cranking should show 5-volt pulses (if it starts and runs, the pulses may occur too often to see). If you get voltage there, then probe the same pins at the coil harness...