MSD 6AL Question?

twobjshelbys · #1 (**permalink**) 08-07-2010, 08:54 PM

My 6A died. It happened right after I washed the engine compartment (note to self, switch off battery kill switch before doing that again.) I futzed around trying to convince myself that it was everything but that - started by replacing the coil hoping for an easy fix. I eventually found the troubleshooting guide at the MSD web site. I did the test to short the coil wire to ground and release and no sparkie. I thought it might be the fuel injection controller which supplies the ignition signal and got an oscilloscope from work and confirmed it was getting the proper input. I ordered a new one and just "dry fitted" it and boom, it worked.

Dwight · #2 (**permalink**) 08-07-2010, 09:10 PM

Lainhart mailed two back to MSD last spring. One tested bad and they repaired it. The other one tested good. I don't think they charged him.

Dwight

Dwight · #3 (**permalink**) 08-07-2010, 09:17 PM

Hey Mark,

I just looked at the picture of your SFP and recognized you. I have that same picture on the wall at the office. We met last June at the Hot Rod Power Tour in downtown Chattanooga.

How are you doing?

I worked my last day at the VW plant Friday. Yahooooooooooooo!!!!!!!!!!

I just remembered I forgot to take the Cobra pictures with me when I left. I'll have to print them again.
Hope to see ya on the road somewhere.

Dwight Frye
Florence, Al

TN Shelby Cobra · #4 (**permalink**) 08-08-2010, 05:39 AM

Thanks for the info guys! I took the Cobra out last week and drove it about 30 miles to a friends house. It was a hot day.Took my friend for a drive after letting it set about 25 minutes. Got on it and it started missing. Took it back to his house and it was running bad and back fring thru the carb. The car started running pretty lean. ( Light grey inside pipes) It doesn't normally run that lean. Went and got my trailer and brought it home . I first thought it might be bad fuel so I changed the fuel filter and drained the tank. Checked the fuel pump ( black inline electric) It is working fine. I changed the carb. ( I was going to do it anyway ) Still don't run. I changed the coil and no difference. (The car has a 392 Ford crate motor ) Car has 7,100 miles on it and I put 1,700 on it since I bought it 4 months ago.The only thing left to change is the MSD box or the MSD billet dist. My box is mounted in the passenger area aboue where you feet are. Its funny cause I took it up to about 6,000 RPM and thats when it started missing like it is suppose to do. ( 6,000 chip is installed) I also pulled the valve covers and everything is fine. I worked on this thing all day yesterday and didn't get no where!!! The past owner gave me all the paper work and the box was been replaced before. ( Car was built in 2004 ) Dwight it is good hearing from you. I have been going to the sonic cruise inn every monday evening. I didn't see you there and figured the heat had got to you from all day at VW!!! I'll let you know when we all get together again down here. Thanks again for all the info everybody. Mark

Blas · #5 (**permalink**) 08-08-2010, 08:27 AM

Many times, problems with a MSD6AL box can be traced to bad wiring. Check the wire connector crimps on all the connections and the general tightness of the wire connectors to their sources. A loose ground or power can pop the internal fuse in the unit.
MSD has easy to follow test procedures on its web site. You can easily check the operation of the MSD box, the coil and magnetic pickup. MSD boxes are kinda like a switch...either they work or they don't... erratic operation suggests looking for an outside problem - installation or connections...if you have a connection to your ignition switch (most people do) the ignition switch is another source of problems. The ignition switch is also easily bypassed to eliminate it as a problem...Bad wire connections at the coil are also something to check...I heard of them being held together only witht the shrink tubing...
Keep of posted of your progress.

CWizard · #6 (**permalink**) 08-12-2010, 09:40 PM

[quote=TN Shelby Cobra;1069996]Thanks for the info guys! .... I have been going to the sonic cruise inn every monday evening.

Mark - Is the Sonic cruise in on Monday? I thought it was Friday, with Sears Northgate on Monday. Chuck (black SPF) and I are planning to show up once the temperature drops below 100. I'd hate to go to the wrong party.

Glad you figured out the ignition problem.
Jerry

TN Shelby Cobra · #7 (**permalink**) 08-13-2010, 05:16 PM

Jerry, Sonic Ooltewah is on Monday nights and Sears Automotive atNorthgate Mall is on Fridays! Let me know when you guys want to go!