MSD 6AL Problems?

[Axel 427]

Still new to Cobra's, but I'm learning, thanks to this forum. I have a 2010 BDR with a Roush small block 427R complete with MSD everything. The ignition box is a 6AL.
Ever since I bought this car last December, it's hard to start, idle's really rough,
and snorts and farts when I half way get on it. I figured since the car only had 300 miles that the carb was maybe gummed up. Today, I drove the car for a hour or so and when I stop to get something to eat the dang car wouldn't start.
It would turn over, but it acted like there was no spark. I disabled the ignition box by pulling the fuses. The car fired right up and actually idled smother and ran a lot better. Is it necessary to have a box?? Is this a common problem with MSD?

Vance

[Gaz64]

Unfortunately for MSD, very common.

I don't run MSD anymore.

Visit the MSD website and forums for more answers.

[Marc Wulf]

You disabled the box and it started?

[Dwight]

the best part of a MSD box is the rev limitor

[Axel 427]

Originally Posted by Marc Wulf

You disabled the box and it started?

Yes sir the car started and runs a lot better!!!

[cbreez]

If it is the box, MSD will fix anything wrong with it for about $50...easier than buying a new box! Check with msd.

btw, they can have a problem with sparking when even slightly warm, when they cool down things are just fine.

[Dwight]

One time MSD did not charge us to repair one. Next time it was $18, another time $80 which was the max they charged at that time.

[twobjshelbys]

Wait a minute...

Didn't anyone see that he disabled the MSD and the car still runs? Please 'splain.

[cbreez]

I think they guy misspoke...you explain...

[Axel 427]

Originally Posted by cbreez

I think they guy misspoke...you explain...

OK..........My inexperience is showing here. Hopefully someone will help me out here. My MSD ignition box 6420 with rev limiter is mounted under the dash. I followed one of the wiring harness down to 2 inline fuses . I removed the fuses. I swear the car runs alot better. Is this possible?

[Gaz64]

Originally Posted by Axel 427

OK..........My inexperience is showing here. Hopefully someone will help me out here. My MSD ignition box 6420 with rev limiter is mounted under the dash. I followed one of the wiring harness down to 2 inline fuses . I removed the fuses. I swear the car runs alot better. Is this possible?

I doubt whether the fuses you have removed are anything to do with the 6AL system.

The ignition system would not function without 12v on the small red wire.

Same for either of the heavy red or black wires.

Does something else not work now?

[twobjshelbys]

Originally Posted by Gaz64

I doubt whether the fuses you have removed are anything to do with the 6AL system.

The ignition system would not function without 12v on the small red wire.

Same for either of the heavy red or black wires.

Does something else not work now?

I looked at the install manual and see no mention of fuses on any of the MSD box wires.... The installer may have used them but not part of the kit.

[Axel 427]

Originally Posted by Gaz64

I doubt whether the fuses you have removed are anything to do with the 6AL system.

The ignition system would not function without 12v on the small red wire.

Same for either of the heavy red or black wires.

Does something else not work now?

Everything works...........Head Lights, blinkers, fan.......
Dang, sorry for my ignorance, I'll look into futher

[Cashburn]

Originally Posted by twobjshelbys

Wait a minute...

Didn't anyone see that he disabled the MSD and the car still runs? Please 'splain.

This ^^^^^

[GLS-BDR226]

I would check the MSD coil. I had one go bad and it would start but wouldn't idle for nothing. Changed the coil and runs great.

[Cobra #3170]

There is a reason NASCAR race cars have two boxes

[cbreez]

Just send the box to msd...if there's nothing wrong they won't charge you...the problem probably not grounding, coil, etc.
Think about it, nothing moves in there sitting in the garage...not a grounding problem.

[allcarfan]

As others have said, there are no fuses for the MSD box...or coil. If you can see the MSD box and try to crank the car and the LED light is firing, it is sending a signal to the coil. I think you said you are running now, so, now its almost impossible to figure out what is wrong. I always like to work my way backwards when checking ignition...check the plugs first, then the ol screwdriver trick on the plug wire, then coil, then MSD box.

I had my MSD Blaster SS coil poop out on mine with 80 miles on it. As soon as I replaced the coil, the car ran fine again. I keep a spare coil in my trunk....just in case. I would be interested to see where your coil is mounted also. I have a thought that the coil may be exposed to excessive heat and may cause premature failure.

[kevins2]

Originally Posted by allcarfan

I had my MSD Blaster SS coil poop out on mine with 80 miles on it. As soon as I replaced the coil, the car ran fine again. I keep a spare coil in my trunk....just in case. I would be interested to see where your coil is mounted also. I have a thought that the coil may be exposed to excessive heat and may cause premature failure.

I also carry a spare coil, 6al box and dist. cap/rotor in the trunk. I had two MSD coils fail the first year on the road (one with only about 100 or so miles on it). Easy road-side fix, but shouldn't fail like that. I asked an MSD technician about heat - mine is bolted to the front of the head. He said it should handle the heat. Not convinced, I used some welder's blanket scraps I had laying around to isolate the coil from metal-to-metal contact. Cut a piece that is slightly larger than the size of the coil itself as a "heat shield" between the bracket and the head. Also, wrapped the coil with a narrow strip where the bracket used to contact it. Made it through this season without another failure (about 4,600 miles). Obviously, can't say heat was an issue, but reducing it a bit couldn't hurt.