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Discussion Starter #1
Alright this is going to be a long one. I am having issues with my MSD setup which consists of:

6530 box (I have two of them here)
8252 coil (two of these also)
85840 distributor (locked out)

Heavy wires direct to battery. Only two wires running to coil. Distributor wires are separate from any other wiring. Battery is grounded to frame, block, and then also a block to frame ground strap.

To start, I had a no spark condition with the first box and coil. Unit was for sure getting 12V from the heavy wires and from the trigger wire. Coil tested just outside of listed tolerance. Distributor tested ok. MSD tech told me the box or coil "had to" be bad.

So I overnight a second box and coil. It now starts every time and has spark. The issue it has is very strange. If you plug the laptop in and check the battery voltage, it will periodically read 15V with the engine off and 18V with the engine running. It will then act as though it has a "two step" set and will not rev over 2000 rpms and the timing goes crazy if you watch with a light. Tach goes crazy.

If I disconnect the battery a few times, the car might run fine until you shut it off again. I unhooked the alternator and had the same result. All retard settings are set to zero or disconnected.

I can literally turn the key on and see 12V. Cycle key and it will show 15V on the software. I have used two different volt gauges and confirmed the box is only seeing 12V. My Autometer volt gauge never changes from 12-12.5V while the software gauge bounces all over

Three different times MSD "techs" have put me on hold and then hang up. The advice they have given me:
-Download new software
-Make sure no wires are touching
-Send boxes in to be checked
-Ignore the voltage gauge in the software


Also another strange thing is that both boxes flash "code two" on the LED indicating low voltage. This is with them connected directly to multiple different batteries that have 12.4V.

The MSD box flashes "low voltage" but the MSD software shows that the box is seeing between 12-15V. This is on both boxes when they are new. I was told to ignore this

Any ideas before I order all Mallory or Crane parts? I'm beyond fed up with MSD and their service. I now have $1000+ in parts and overnight fees plus going on three weeks of headache

I've asked if it could be anything in the programming and they said no. I can post how I have it setup if need be. I typed this out on my phone so it is probably full of errors

Any ideas? Thanks
 

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Discussion Starter #2
Just to add:

I really want to assume that the issue was in my wiring or my program and think that I surely couldn't get bad "out of the box" pieces in a row like this; but I'm starting to doubt the parts as I narrow everything down

My two step is set to 3000
Rev limit is 7400
Burnout limit is disconnected
Run retard is zero across the graph
No MAP sensor
 

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Check the voltage at the red (ignition) wire while cranking it. If that number is below 9 when cranking the box will not fire or behave correctly. Also do you use a shielded wire from your box to the distributor / crank trigger pickup? This sometimes helps if there are interference issues. God luck.

Rich
 

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Discussion Starter #4
Check the voltage at the red (ignition) wire while cranking it. If that number is below 9 when cranking the box will not fire or behave correctly. Also do you use a shielded wire from your box to the distributor / crank trigger pickup? This sometimes helps if there are interference issues. God luck.

Rich
Thanks for the reply. I am not using a shielded wire, just the two-wire harness that came with the box. I'm going to check again today and make sure it isn't touching any other electric source whatsoever.

What has me baffled is the engine ALWAYS starts (and easily at that) but will sometimes act like it has a two step activated and other times it won't. This is with the "launch" wire getting no voltage

It almost seems like if I rev the engine to 3000 or so as soon as it starts, then it will run like normal (sometimes)

Could anything with the distributor pickup give symptoms like this?

If I do rev it when starting, it will run for however long I want it to. Revs clean
 

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The very first thing I would do is get my ass in gear and get a REAL voltmeter, not software.
 

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Discussion Starter #10
Sorry, man. Thought you were talking about software.
I am comparing the two to try and make sense of the way the box is acting. I just happened to notice the high voltage when it was acting crazy. It could have nothing to do with the issue at all though
 

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Discussion Starter #11 (Edited)
OK I completely rewired this box today with a new harness.

-Distributor pickup harness was completely by itself/ not touching any other wires
-"Heavy" wires to battery
-Trigger wire also to battery on switch
-Only orange/black wires going to coil
-12.4V at battery

-Car started and ran decent (possibly slight miss but I'm on E85 which doesn't run that great below 150-160). Software showed 12V

-Shut off. Immediately restart and now won't go over 2000 rpm again. Tach still goes crazy. Software shows 17V now

-Shut off. Restart again and will rev like normal with still a slight miss (not too worried about the miss)

This was all done with the alternator unhooked. When the MSD software is saying 12V, my gauge says the same. When it said 17V, my gauge was down to 11.9V.

It also doesn't like to idle much below 1000 rpm (but that might not be related to this)

Is there ANYTHING that could make it do this on my end? If it was a programming error, would it run fine until restarted and then have a mystery "two step" like this? Restart again and possibly go away?

It really has me baffled. Could the pickup in the distributor do this? The "air gap" is .032" and I measured 600ohm
 
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