Ignition failure
#1
06-08-2012, 11:21 PM
Ignition failure
I was on way home when truck died. Although I didn't have many tools, I managed to ck a few things. I have gas squirting in carb. Engine cranks fast and long, but zero spark from coil to dizzy.
I have an MSD box with msd tfi coil, with ds2 dizzy. I also popped the cap on the dizzy, and was surprised how bad the rotor and contacts looked, so I sanded them a bit. Sunday I'll ck the ground and connections, and of course the hot line to and from the msd box, etc., but thought maybe someone might throw in something I wasn't thinking of.
I've noticed engine hesitating when cold, tiny backfire through exhaust when cold and I acc., but I've been playing with choke and thought it was b/c of that.
Thanks, guys, for any help.
I have an MSD box with msd tfi coil, with ds2 dizzy. I also popped the cap on the dizzy, and was surprised how bad the rotor and contacts looked, so I sanded them a bit. Sunday I'll ck the ground and connections, and of course the hot line to and from the msd box, etc., but thought maybe someone might throw in something I wasn't thinking of.
I've noticed engine hesitating when cold, tiny backfire through exhaust when cold and I acc., but I've been playing with choke and thought it was b/c of that.
Thanks, guys, for any help.
#3
06-09-2012, 06:36 AM
Yes, it is still dead. I won't have time to ck anything until Sunday. That is also the day of the auto swap meet, so may be able to p/u any needed parts there.
AB--I'll certainly ck the msd box. It is only 3 years old. I hope that is not the problem. If it is, I may switch to the GM 4 pin system so I can carry a spare in the truck. Cheers.
AB--I'll certainly ck the msd box. It is only 3 years old. I hope that is not the problem. If it is, I may switch to the GM 4 pin system so I can carry a spare in the truck. Cheers.
#4
06-09-2012, 04:15 PM
#5
06-09-2012, 10:41 PM
Thanks for the tip. I'll ck everything out Sunday. B/c of your response I'll hit the j/y and grab a FoMoCo tfi coil just in case. If it is the coil, I'll have a back up. If not, then I'll have for down the road. Thanks. k
#6
06-10-2012, 03:04 AM
Elder User
I personally would be surprised if the MSD box is at fault. I get people all the time at work trying to bring back MSD boxes, claiming that they're bad, and that their car won't start/has a dead spot/won't rev past a certain RPM because of a 'bad box', and the first thing we do is hook the box and their harness to a tester and test it in front of the customer. With the tester, we can test the boxes all the way up to something crazy like 18,000 RPM, and I've never seen one that's legitimately bad, all of them put out a strong discharge. I've seen guys pull those boxes out of the burned remains of their car, bring them in and still test good. My boss has been at that Summit Racing location since it opened in 2006, and he's only seen one that was legitimately bad. Now, that's not to say that you don't have a bad box, it's entirely possible, and maybe even probable. Who knows, something may have gotten shorted out, I don't know, but I've seen those MSD boxes put through some hell, and they keep coming back for more. Now, I can't speak for your coil or distributor at all. Though I've never personally seen one go bad, I've never really tested one either, so that could be your problem. Not entirely sure why I felt the need to rant about the MSD box, but I did. Rant over.
#7
06-10-2012, 07:46 AM
Here is a simple test for MSD if it applies. Don't know where I got it, but saved as a pdf on my computer.
I've run across too many failures (real or not, cars don't run) over the years with these boxes.
IMHO, I would go with HEI and never look back, totally reliable as long as a good heatsink and heat compound is used.
If using an hei style dist, then recurving the advance is super easy since the weights springs and curve plate ane on top, easy to get to.
Hope your solution is as simple as a bad connection or coil.
How to Check Your MSD Ignition Box
For the Racer who feels they have a failed MSD®Ignition, there is a simple test that walks you through to confirm a true failure of your MSD®Ignition.
First you will need a Volt/Ohm meter (this check can be performed with an analog or digital meter as well). The type of meter will not change the outcome of the test performed. Set your volt/ohm meter on the 1k ohms scale, then position the MSD®Ignition in approximately the same orientation as mounted in the vehicle. This is done to ensure that the MSD®Ignition is relatively in the same position as when the failure occurred. Next take either lead and attach it to a bare metal area on the MSD®Ignition. The second lead needs to be hooked to the Large Red wire that provides your main 12vdc input. In an Undamaged MSD®Ignition the needle will stay in the home position (i.e. max Ohms for scale chosen). A Damaged MSD®Ignition will show a reading of 3k ohms or lower.
The readings mentioned above are the result of experience with repairing MSD®Ignition systems. If you plan on testing your MSD®Ignition while it is still mounted in your vehicle PLEASE remove the LARGE RED wire (i.e. main 12vdc). Failure to do this will result in possibly damaging your meter while performing this test on your MSD®Ignition.
Troubleshooting MSD ® Ignition 6A, MSD ® Ignition 6AL, MSD ® Ignition 6T, MSD ® Ignition 6ALN, MSD ® Ignition 6TN, MSD ® Ignition HVC 6600, MSD ® Ignition 7AL-2
MSD ® Ignition High Speed Miss:
Check the main ground connection & + 12VDC connection on the MSD ® Ignition box for a good connection. Also look at the Orange & Black coil wire connectors coming out of the MSD ® Ignition for poor fit or wire corrosion. Check to make sure that the second trigger input out of the MSD ® Ignition is not shorting to ground. IE (the trigger you are not using). If you have taped it off make sure it is still clean and dry with no way to make a connection to ground!
MSD ® Ignition RPM limited / flat performance of a MSD ® Ignition:
Check the small Red wire coming out of the MSD ® Ignition for a loose connection or a poor wire connection at the switched +12vdc. A loose main Black ground wire out of the MSD ® Ignition to the chassis ground / Battery ground. Check to make sure you have a solid +12vdc to the MSD ® Ignition box. If the voltage drops below +10.35vdc the MSD ® Ignition can start to cause gremlin kind of issues. Check the Orange & Black ignition coil wires coming out of the MSD ® Ignition at the coil side for poor fit or bad crimping of the connector.
MSD ® Ignition will not start the vehicle:
You will want to start with the Basics. Make sure you have a solid +12vdc & Ground to your MSD ® Ignition check all connection points! Check the small Red wire coming out of the MSD ® Ignition box for breakage and poor connection at the switched +12vdc source. Make sure the+12vdc being supplied is not drifting around on your MSD ® Ignition, this will cause your unit to do dumb things. Remember if the voltage gets below the +10 volt range the MSD ® Ignition box will shut down period.
A 6A or 6AL either will work but if you want more punch on the output of the box then the 6al is the better choice. If you are you running with the Blaster 2 coil, you need to move up to either of the following coils - AutoZone C-839 or CarQuest FD-478. They are TFI type coils, they are quicker reacting then the Blaster2 and Do Not heat soak and lose output. And as a side benefit they are the units that MSD sells as the HVC stuff at a high price! These coils will get everything out of your MSD box there is to get, the only thing you will need to do is make a mounting bracket. Use aluminum L channel, a couple of bolts and Ny-lock nuts & ready to roll. Also these coils can be mounted in any orientation and still function they don't care.
For the Racer who feels they have a failed MSD®Ignition, there is a simple test that walks you through to confirm a true failure of your MSD®Ignition.
First you will need a Volt/Ohm meter (this check can be performed with an analog or digital meter as well). The type of meter will not change the outcome of the test performed. Set your volt/ohm meter on the 1k ohms scale, then position the MSD®Ignition in approximately the same orientation as mounted in the vehicle. This is done to ensure that the MSD®Ignition is relatively in the same position as when the failure occurred. Next take either lead and attach it to a bare metal area on the MSD®Ignition. The second lead needs to be hooked to the Large Red wire that provides your main 12vdc input. In an Undamaged MSD®Ignition the needle will stay in the home position (i.e. max Ohms for scale chosen). A Damaged MSD®Ignition will show a reading of 3k ohms or lower.
The readings mentioned above are the result of experience with repairing MSD®Ignition systems. If you plan on testing your MSD®Ignition while it is still mounted in your vehicle PLEASE remove the LARGE RED wire (i.e. main 12vdc). Failure to do this will result in possibly damaging your meter while performing this test on your MSD®Ignition.
Troubleshooting MSD ® Ignition 6A, MSD ® Ignition 6AL, MSD ® Ignition 6T, MSD ® Ignition 6ALN, MSD ® Ignition 6TN, MSD ® Ignition HVC 6600, MSD ® Ignition 7AL-2
MSD ® Ignition High Speed Miss:
Check the main ground connection & + 12VDC connection on the MSD ® Ignition box for a good connection. Also look at the Orange & Black coil wire connectors coming out of the MSD ® Ignition for poor fit or wire corrosion. Check to make sure that the second trigger input out of the MSD ® Ignition is not shorting to ground. IE (the trigger you are not using). If you have taped it off make sure it is still clean and dry with no way to make a connection to ground!
MSD ® Ignition RPM limited / flat performance of a MSD ® Ignition:
Check the small Red wire coming out of the MSD ® Ignition for a loose connection or a poor wire connection at the switched +12vdc. A loose main Black ground wire out of the MSD ® Ignition to the chassis ground / Battery ground. Check to make sure you have a solid +12vdc to the MSD ® Ignition box. If the voltage drops below +10.35vdc the MSD ® Ignition can start to cause gremlin kind of issues. Check the Orange & Black ignition coil wires coming out of the MSD ® Ignition at the coil side for poor fit or bad crimping of the connector.
MSD ® Ignition will not start the vehicle:
You will want to start with the Basics. Make sure you have a solid +12vdc & Ground to your MSD ® Ignition check all connection points! Check the small Red wire coming out of the MSD ® Ignition box for breakage and poor connection at the switched +12vdc source. Make sure the+12vdc being supplied is not drifting around on your MSD ® Ignition, this will cause your unit to do dumb things. Remember if the voltage gets below the +10 volt range the MSD ® Ignition box will shut down period.
A 6A or 6AL either will work but if you want more punch on the output of the box then the 6al is the better choice. If you are you running with the Blaster 2 coil, you need to move up to either of the following coils - AutoZone C-839 or CarQuest FD-478. They are TFI type coils, they are quicker reacting then the Blaster2 and Do Not heat soak and lose output. And as a side benefit they are the units that MSD sells as the HVC stuff at a high price! These coils will get everything out of your MSD box there is to get, the only thing you will need to do is make a mounting bracket. Use aluminum L channel, a couple of bolts and Ny-lock nuts & ready to roll. Also these coils can be mounted in any orientation and still function they don't care.
IMHO, I would go with HEI and never look back, totally reliable as long as a good heatsink and heat compound is used.
If using an hei style dist, then recurving the advance is super easy since the weights springs and curve plate ane on top, easy to get to.
Hope your solution is as simple as a bad connection or coil.
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#8
06-10-2012, 01:50 PM
First, thanks for all the input guys. I hope I'm not making a mistake, but I don't have an oem meter, just a 'bug light,' to tell me if there is juice in a line. After testing with a bug light connected to my volt function on my dwell meter, I can see I have both direct power from battery and ign. positive from key going into msd box. But when I crank the engine over, neither the coil lead or the one to the dizzy show any power.
That pretty well says that the power is failing to exit the msd box. I have to get the truck running today, so I'm off to pick up the GM 4 pin module, and do the conversion, with a spare in glove box. After only three years, I'm not impressed by the msd.
That pretty well says that the power is failing to exit the msd box. I have to get the truck running today, so I'm off to pick up the GM 4 pin module, and do the conversion, with a spare in glove box. After only three years, I'm not impressed by the msd.
#9
06-10-2012, 02:34 PM
I couldn't find info here with a search, so went to gofastforless.com and found the GM 4pin HEI ign. module, and found how to connect to a ds2 dizzy. $23.99 new @ O'reiley's, lifetime warranty.
The only thing that concerns me is he says to install on a heat sink. I assume that is an alloy piece with heat dissipating fins? And Shazzam! I got a DUI dizzy!
The only thing that concerns me is he says to install on a heat sink. I assume that is an alloy piece with heat dissipating fins? And Shazzam! I got a DUI dizzy!
#10
06-10-2012, 02:53 PM
Postmaster
There's a made-to-order heat sink:
Amazon.com: ACDelco 10474610 Ignition Module Heat Sink: Automotive
Amazon.com: ACDelco 10474610 Ignition Module Heat Sink: Automotive
#11
06-10-2012, 05:05 PM
Originally Posted by F-250 restorer;11936612[SIZE=2
x. But when I crank the engine over, neither the coil lead or the one to the dizzy show any power.[/SIZE]
I didn't catch this when you explained the process..
I usually check both the + and _ sides first to see "hot" when key on, (+), then "blinking" (-), when cranking...but kudos...Hopefully your "4pin" solution will work for you.
FYI, I happen to be at the intersection of "durasparking" a NEW2ME 86" Bronco I-6 300 and am in the middle of "that" decision myself. Will watch with interest.. I have a couple 4pin modules, and a heat sink already just haven't decided to do this yet...but since i want the TFI coil that's already mounted on the side of the block..It's probably the best solution...good luck
#12
06-10-2012, 10:01 PM
[quote=JohnSmith3524;11937096]I hope not 2 embarrass myself, but you DID check the + side of the coil with your "bug" light..and it is "on" when you turn your ign "on" right?..
I didn't catch this when you explained the process..
I usually check both the + and _ sides first to see "hot" when key on, (+), then "blinking" (-), when cranking...but kudos...Hopefully your "4pin" solution will work for you.
With the msd box you have the ign + goes into box, and the coil + comes out of bx. I had power going into msd box, but could not get power to the coil + lead, with the key on.
Then, with the 4pin installed, I could not get spark from msd tfi coil. As soon as I swapped Autozone C-839, boom, I was down the road, once I reset the timing and adjusted the carb.
I am very surprised to have both the msd 6a and the msd tfi coil both fail at the same time, as though there was a timer inside that expired!! Anyway, my $250 worth of trick crap failed after three years, and for about $50 I was able to replace it. I bought new ones since there wasn't that much of diff between j/y and AZ prices. And, with the 4pin I got a life time warranty, and opted to splurge for an extra 'top-of-the-line-quality' Borg Warner. Big spender.
Next time I hit the j/y I'll pull an extra 4pin, along with the oem heat sink, and keep the module in the glove box.
I didn't catch this when you explained the process..
I usually check both the + and _ sides first to see "hot" when key on, (+), then "blinking" (-), when cranking...but kudos...Hopefully your "4pin" solution will work for you.
With the msd box you have the ign + goes into box, and the coil + comes out of bx. I had power going into msd box, but could not get power to the coil + lead, with the key on.
Then, with the 4pin installed, I could not get spark from msd tfi coil. As soon as I swapped Autozone C-839, boom, I was down the road, once I reset the timing and adjusted the carb.
I am very surprised to have both the msd 6a and the msd tfi coil both fail at the same time, as though there was a timer inside that expired!! Anyway, my $250 worth of trick crap failed after three years, and for about $50 I was able to replace it. I bought new ones since there wasn't that much of diff between j/y and AZ prices. And, with the 4pin I got a life time warranty, and opted to splurge for an extra 'top-of-the-line-quality' Borg Warner. Big spender.
Next time I hit the j/y I'll pull an extra 4pin, along with the oem heat sink, and keep the module in the glove box.
