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67DARTGT
09-27-2003, 03:38 PM
My msd 6al died. It came with the car and looked really old so i decided to replace it with the Digital 6 Plus unit b/c i liked the added features. I installed the unit without any problems and the wiring was simple enough. Now my problem is the car cranks up but *POPS* really loud back through the exhaust pipes. It sounds so bad i'm afraid to run the car for more than a few seconds. This is a big block mopar with the stock electronic distributor. I'm using the green and violet wires for the distributor as instructed in the installation manual and i have cut the green loop as instructed. These violet and green wires are away from any plug wires that might interfere with anything. The start retard feature is set on the #2 position which shouldnt be giving me any kind of start igntion timing retard, right? Where should i start looking for my problem?

Thanks a bunch.

msdtech1
09-27-2003, 09:12 PM
The cylinder select dial should be in the number 2 position. This will program the unit for 8 cylinder operation without any start retard. Where do you have the Pink and the Blue wires hooked to? Make sure that you only have the Orange wire connected to coil positive and the Black wire to coil negative. No other wires should touch the coil terminals. What is the color of the wire on the distributor that you have the Violet wire attached to?

MSD Tech1

67DARTGT
09-28-2003, 08:37 AM
I do not have the pink or blue wire connected to anything. I have them both wound up and tucked away. Maybe i should tape up the bare exposed wire on the end of each? Checked coil wires again and they are correct. The wires coming from my distributor arent black and orange as stated in the wiring diagram they are black and grey. The grey wire has some orange specks on it like maybe at one time or another it was orange. So i went ahead and hooked the voilet wire to the grey one with the orange specks. I hooked the green wire to the black. At this point the motor would crank and pop through the exhaust horribly. I tried swapping the wires around.......hooking green to green to grey wire with orange specks and violet to black and nothing at all would happen. The LED light on the unit will come on and i'm gettin fire at the dist. cap but the motor will not hit. After a few seconds of tryin to crank the motor the LED light will go out totally, but will come back on if i totally turn off the igntion and cut it back on. I'm stumped. Could the unit somehow be messing with the timing causing the starting and popping problems. I didnt mess anything up by swapping connections with the green and violet wire did i? :( could the box be producing some much spark its crossing to different terminals inside the cap?? The wires are almost brand new.....Accel 300+ race wires and the coil is an MSD blaster 2. The stock mopar alternator has been replaced with a GM one wire unit. All of these parts worked fine with the old MSD 6AL box so i dont know what to do next.

Thanks for the help.

67DARTGT
09-28-2003, 01:26 PM
I tried a few different things this afternoon. I Ran another ground for the Digital 6 box. Changed my red 12 volt ignition wire to another source of power. Played with the initial timing. None of these things seem to have helped. I can get the car cranked but it runs horribley, missing, spitting, not hitting on all 8. The Digital 6 Plus unit is mounted inside the passanger compartment under the dash, on the firewall beside the MSD blaster 2 coil if that makes a difference. I watched the LED light as i cranked the engine and it stays lit when the engine is running but when the engine dies so does the light. The light will come back on if i turn the ignition off, and then back on. The light also stays lit while cranking unless the engine hits and doesnt crank up. If the engine hits, the light goes out and again will come back on if i turn off the ignition then turn it back on. If i send the box back to MSD to get it checked out the box turns out ok, what kind of charge will i be looking at for testing the unit? I'm almost convinced the problem lies in the MSD box weither it be a manufacturer defect or my mixing up of the distributor wires for the green and violet wires. Either way please point me in the right direction.

Thanks

msdtech1
09-28-2003, 09:40 PM
The wiring on the distributor sounds correct. The LED is telling you that the MSD received a signal from the distributor and has triggered the MSD. When the engine quits, so does the trigger input from the distributor, so ttherfore the LED stops flashing. You said that the unit came with the car, do you know if it ever worked before? Have you tried it on another vehicle to see if it works? Let me know.

MSD Tech1

67DARTGT
09-29-2003, 03:11 PM
No the old 6AL came with the car......not the Digital 6 Plus. I just purchased the digital 6 last week. The 6AL died so i upgraded to the digital 6. I tested the old 6AL using the procedure described in several other posts.....jumping across the green and violet wires to determine that it was bad. Like i said i can get the car to crank but it runs like crap. I'm going to try and crank it this evening in the dark to maybe see if anything is arcing. Also, i tried jumping the green and violet wires on this box it make the coil fire....but it wont fire consistently. Sometimes it will create a spark and other times not. Any ideas?

Thanks for the help.

67DARTGT
09-29-2003, 05:35 PM
Just tried cranking the car in the dark and saw no arcing. I did however pull the coil wire off of the cap and put the wire close to a ground to observe the pattern of the arc coming from the coil wire. I'm not getting spark on every cylinder. I observed spark arcing from the coil wire only 3 or 4 times on each complete engine rotation. So......for some reason the coil is not firing 8 times on each complete engine rotation. Getting very frustrated.

Thanks for your patience

msdtech1
09-29-2003, 10:30 PM
Her are a couple more suggestions to look at. Inside the distributor, there is a reluctor with 8 poles (paddles) on it. Check to make sure that none of the paddles are damaged or broken off. Also, how fast is the engine spinning while cranking the engine. If it is not spinning fast enough the trigger pickup in the distributor may not be triggering the MSD unit because of a weak signal.

MSD Tech1

67DARTGT
09-30-2003, 04:08 PM
checked the "paddles" that are used by the pickup. All of them look fine. I then hooked up a spark plug wire checker to the plug end of each wire to check for fire at each individual cylinder. I have NO fire on cylinders 3 and 4. #1 cylinder fired once, but not consistently after that. The other cylinders have fire. I then used a ohm meter to see if the wires on cylinders 1, 3, and 4 were good. They checked fine. How come i'm not firing on all cylinders? Its been my experience that distributor pickups either work or they dont, so i wouldnt think the pickup would be bad since i have fire on some of the cylinders. What other tests and/or options do i have before i have to unbolt, unwire, box up, and ship back this unit to be tested???

msdtech1
09-30-2003, 11:05 PM
The MSD has no idea which cylinder it is on. The only part that tells the unit to fire is the pickup and reluctor inside the distributor. If you are running a chrysler distributor, the gap between the pickup and the reluctor needs to be very small. You may need to reduce the gap slightly to get it to trigger corectly.

MSD Tech1

67DARTGT
10-01-2003, 06:22 PM
I'll be sure to try it.

Thanks!

msdtech2
10-02-2003, 02:49 PM
No problem.
msdtech2

67DARTGT
10-05-2003, 02:33 PM
well the pickup/reluctor gap was the problem. Mopar recommends a gap of .008 to .010 and the gap was around .018. Its a wonder it even ran at all. Thanks for all the help and assistance. I think this tech support forum is a great idea and will save MSD and its customers alot of hassle.

Keep up the good work. :)

msdtech1
10-07-2003, 10:30 PM
We appreciate that very much.

Thank you,

MSD Tech1

67DARTGT
11-09-2003, 06:14 PM
Unfortunatly I am back with the same problems I had before. I adjusted the reluctor gap and thought i had the problem fixed. The car is still giving me the same symtoms as before. It has fuel, fire , and compression but will not run. Its been a while since my last post b/c i've been tryin everything i know to figure this out including going back over what i have already double checked. I'm wondering is there any way to test the ignition start retard function of the Digital 6 box?? I'm wondering if maybe the msd unit is retarding my timing to much. I have the box set for zero timing retard at the moment. I have layed the distributor end of the coil wire near a ground and touched the green and violet wires together and i have a strong spark. I'm stumped. Short of replacing the msd digital 6 with something else i dont know what to do.

67DARTGT
11-11-2003, 06:02 PM
helloooooooooooo

msdtech4
11-12-2003, 11:00 AM
67DARTGT,

It is not the box or coil since you can trigger the box and it sparks. That is all the box can do, fire when it is told to. If you have the start retard feature on the off position, number 2 on the selector, then the start retard is out of the picture. Move the air gap on the pick up down to .005 and see if this helps. the mopar pickup's are inherently weak and it is not uncommon to need to have the air gap tighter then the "factory recommended" gap. Let me know

Thanks,

MSD tech4

67DARTGT
11-18-2003, 06:43 PM
ok tightened up pickup reluctor gap to .005 with no change. Still wont crank. Tried starting fluid and it would sometimes hit but never crank up and run. I'm stumped. I have fuel, i have fire, i have compression, timing is right, cap and rotor are new, car ran fine before old box died. I have seen with my own eyes that i have fire at the plugs but could it be i'm losing spark at the plugs when they are under compression in the cylinder due to something faulty?? Never have i come across anything like this and i've wired up several systems in the past. Any suggesstions would be appreciated.

msdtech4
11-19-2003, 03:23 PM
67DARTGT,

That could be the case. If it is easier for energy to jump someplace else under compression it will. That includes the cap the rotor the wires and the plugs. the grounds to the motor become important because if this is bad or questionable the energy will find an easier path to ground. And you are sure that nothing goofy like the intermediate shaft jumped, role pin in the gear broke or anything that would throw the timing way off.

Thanks,

MSD tech4

67DARTGT
11-22-2003, 07:49 PM
Ok car is running now. Dont know if problem is totally fixed but it will fire up and idle now. It seems the timing was WAY WAY off. I checked the timing previously but was convinced it was correct. It infact was so far off the timing mark i was looking at was another timing mark on my balancer that was 90 degrees away from the real TDC mark on the balancer. As to how the timing got that far off has me puzzled as the motor has a brand new timing set which i doubt has jumped time, and the distributor was in the exact same spot as with the old 6AL box. Either something fishy is going on inside that distributor or the old and new msd units didnt read the signal from the pickup in the same fashion. Either way i'm releaved that the problem is identified. Thanks for the all help. Hopefully, i wont need to come back! :)

msdtech4
11-24-2003, 03:45 PM
67DARTGT,

The only thing that will change the timing is if the polarity is reversed from one box to the next. You can try reversing the magnetic pick up and the most retarded reading is the correct reading. That is the only way the timing would change. Secondly make sure you are setting the timing with a non-adjustable timing light, it can not have the dial back or digital type timing light.

Thanks

MSD tech4

67DARTGT
11-25-2003, 06:42 PM
ok so swapping the connections for the green and purple pickup wires can affect the timing? also, why cant i use timing light with an adjustable advance knob? do i understand this correctly? if so, how am i supposed to check the total timing since i cant use my timing light with adjustable advance? i always have the timing light knob set on 0 for checking initial timing. i'm not sure if i understood your responses correctly.

msdtech4
11-26-2003, 03:11 PM
67DARTGT,

You will need to use a timing tape like our 8985. The adjustable type lights can be interfered with and will give you an inaccurate reading. Even with them set at zero.

Thanks,

MSD tech4

67DARTGT
11-26-2003, 07:39 PM
ok, but what about the reversing of the trigger wires for the pickup, please clarify. Also, how can interference from the MSD affect an adjustable advance timing light, and not affect a standard non-adjustable timing light? This is the first i've ever heard of this so i'm trying to find out as much as possible. Thanks

67DARTGT
12-01-2003, 06:39 PM
...................?

msdtech4
12-03-2003, 04:16 PM
67DARTGT,

The polarity on a magnetic pick up will actually change the timing when you reverse it. If this is wrong the timing will not do what it is supposed to. It can fluctuate advance or retard as the RPM changes. As for the lights the delay circuitry in the light will be interfered with the output of the box. This will show the wrong timing marks scattering marks no marks etc. These lights are never recommended when you use a CD type or high output ignition.

Thanks,

MSD tech4

67DARTGT
12-05-2003, 12:32 PM
OK thanks again for all the assistance, much appreciated.

msdtech4
12-05-2003, 04:11 PM
67DARTGT,

Let me know how it goes.

Thanks,

MSD tech4