MSD died, diagnosis help needed.
Thread Starter
Pro
Joined: Jan 2006
Posts: 526
Likes: 1
From: Millington TN
MSD died, diagnosis help needed.
Wow, what a start to a weekend. The movers came today and took away everything in my house. I am stuck here til Monday to get the carpets cleaned. I ran out on a quick errand and when I got back in the car I fired her up and she ran for about 10 seconds before dying.
I'm not getting any spark at the distributor. I pulled the cap and it does spin but when I pulled the plug from the coil to the distributor there was no spark. I tried doing a search and couldn't find a good thread that will help me diagnose what the problem is. I am running a MSD6AL with a tach drive billet distributor and a Blaster2 coil. How can I figure out which of these parts has gone bad on me? I am trying to leave town on Monday and this is just rotten timing. What do you guys suggest? Thanks in advance.
I'm not getting any spark at the distributor. I pulled the cap and it does spin but when I pulled the plug from the coil to the distributor there was no spark. I tried doing a search and couldn't find a good thread that will help me diagnose what the problem is. I am running a MSD6AL with a tach drive billet distributor and a Blaster2 coil. How can I figure out which of these parts has gone bad on me? I am trying to leave town on Monday and this is just rotten timing. What do you guys suggest? Thanks in advance.
Melting Slicks
Joined: Apr 2005
Posts: 2,777
Likes: 105
From MSD Tech Support:
The way to test the MSD Unit, you will disconnect the white wire from the yellow on the timing control.
Disconnect the coil wire at the distributor cap and lay 1/4 from ground, this is where it will spark.
Turn the ignition key to the "ON" position, do not crank, make sure there is 12 volts at the small red wire of MSD.
Take the white wire of the MSD 6 Unit and touch and release from ground, every time you touch and release from ground it will spark at the coil wire.
If you do not get a spark, swap the coil with a different coil, it doesn't have to be new, as long as it is a good working coil.
Do the same test, if you get a spark then it was a bad coil, if you still do not get a spark then you know it is a bad MSD unit, but double check that all connections are good and tight.
Thanks,
msdtech2
The way to test the MSD Unit, you will disconnect the white wire from the yellow on the timing control.
Disconnect the coil wire at the distributor cap and lay 1/4 from ground, this is where it will spark.
Turn the ignition key to the "ON" position, do not crank, make sure there is 12 volts at the small red wire of MSD.
Take the white wire of the MSD 6 Unit and touch and release from ground, every time you touch and release from ground it will spark at the coil wire.
If you do not get a spark, swap the coil with a different coil, it doesn't have to be new, as long as it is a good working coil.
Do the same test, if you get a spark then it was a bad coil, if you still do not get a spark then you know it is a bad MSD unit, but double check that all connections are good and tight.
Thanks,
msdtech2
Melting Slicks
Joined: May 2004
Posts: 2,737
Likes: 837
From: Gulf of America
2023 C7 of the Year Finalist - Unmodified
2018 C3 of Year Finalist
http://www.msdignition.com/page.aspx?id=3206
In my case, it was the pickup. I now carry an extra one in the car.
In my case, it was the pickup. I now carry an extra one in the car.
Thread Starter
Pro
Joined: Jan 2006
Posts: 526
Likes: 1
From: Millington TN
Thanks for the tips guys. I need to remember that there are resources other than this forum! I replaced the coil and now I get the spark that the MSD site spoke of. The car still won't start though. I'm getting oil pressure when it turns over but it won't catch. The gas smells a bit funny. Could a bad tank be my issue? I tried carb cleaner and that didn't do it either. It will sometimes catch just a little but never fire up. I have 12 volts to all the systems too. What's next?
Le Mans Master
Joined: Sep 2004
Posts: 5,116
Likes: 5
From: Livonia MI
You didn't mention the age of the fuel in your tank, as could be a biggie, especially in warmer climates. If you think it's stale, replace it, and your plugs, as could have gotten fouled too. In fact, may have caused the bad coil. You'll be needing to get fresh fuel through the lines, into the carb bowls, before re-start too. You can usually get rid of the old gas, by mixing a little into your daily cars tanks.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
Le Mans Master
Joined: Oct 2002
Posts: 7,098
Likes: 378
From: Las Vegas - Just stop perpetuating myths please.
Where are u looking at the spark?
Thanks for the tips guys. I need to remember that there are resources other than this forum! I replaced the coil and now I get the spark that the MSD site spoke of. The car still won't start though. I'm getting oil pressure when it turns over but it won't catch. The gas smells a bit funny. Could a bad tank be my issue? I tried carb cleaner and that didn't do it either. It will sometimes catch just a little but never fire up. I have 12 volts to all the systems too. What's next?
cardo0
Le Mans Master
Joined: Sep 2004
Posts: 5,116
Likes: 5
From: Livonia MI
Gotta agree with "cardo0", as may still be a spark issue. If not already, you can pick up a spark tester from most auto parts for a few bucks. Doesn't sound like bad fuel, since you just topped off, but you never know. If thinking a possibility, I have(or maybe borrow one) an old Gumout #7880 carb clean out kit. Pretty basic, but allows you to run your car from a small can of fuel(or Gumout) hanging from the hood, independent from the cars main fuel source. Actually a pretty handy tool to have.
Thread Starter
Pro
Joined: Jan 2006
Posts: 526
Likes: 1
From: Millington TN
I tried the MSD test again this AM and got no spark. After scratching my head for a bit I installed the new box and presto, she fired right up. I nearly crapped my pants when the backfire came outta the side pipes in my little garage but that's another story. I hope one day I can start doing a little more of the helping around here. Thank you all! 
Thread Starter
Pro
Joined: Jan 2006
Posts: 526
Likes: 1
From: Millington TN
Well I spoke too soon. I went out for a test run and about a mile out the car sputtered backfired and died. I waited a few minutes and she fired right back up and I made it back to the house OK. Frustrating stuff.
Pro
Joined: Jun 2004
Posts: 543
Likes: 2
From: Miami FL
St. Jude Donor '11, '14
Is the MSD seeing a lot of heat? that can kill them temporarily. Same with a coil mounted horizontally. Also, are the power wires lengthened? If so, did you go at least one size larger?
With ignitions, intermittent failures are typically heat or connection related.
Rob
With ignitions, intermittent failures are typically heat or connection related.
Rob
Melting Slicks
Joined: Oct 2002
Posts: 2,317
Likes: 111
From: St Louis MO
When it died, are you sure that the carb had fuel? Pull the air cleaner and pull on the throttle linkage, looking for fuel coming from the squirters. If absent, most likely, the fuel pump is bad, or the fuel filters (the sock in the tank, or the inline filter is clogged.)
Good luck!
Good luck!