View Full Version : Multi-function Controller Problems ..lots
10-05-2003, 07:09 PM
I just installed a 8979 Multi-Function controller and am having multiple problems with it. Old set-up was an Accel magnetic pickup distributor, Accel DragraceII coil and a MSD 7AL2 ignition box, with a 2-step and a RPM window switch.
I installed the 8979 and locked out the distributor by removing the springs and turning the advance plate fully one direction and running a screw through both plates. Power for the 8979 comes from the ignition wire feeding the 7AL2. I bought an connector end kit from MSD for the wires coming from the accel distributor to plug into the 8979 mag input and attached the points trigger wire to the 7AL2. Timing with zero retard functions is set at 36 degrees.
Program was set with 20 degrees start retard, 15 degrees run retard at 800 ramping up to 0 degrees at 3000 RPM.
Now when I go to start the car the timing seems to stay at full advance and the engine fights being turned over unless I flip a switch feeding the ignition to let the motor turn over then flip power back to the ignition to fire it. Once started it runs very erratic and the tach needle bounces all over the place ( from zero to 7000-8000) for a while before finally smoothing out. This usually lasts about 10 seconds. Also when trying to start the motor is seems to start but kill immediately after I release the key from the start position. Like it will ony work while the starter is engaged. It does this about 5-6 times then starts but really rough like I said earlier.
Next problem, once started and running smoothly I tried to make a pass at the 1/4 mile. Car launched fine off the trans brake and pulled hard until 7000 RPM then backfired. Shitfed to second and pulled until 6000 then backfired and would continued to do so if I tried to go past about 3/4 throttle. Weather conditions were almost exactly as last pass without 8979 attached so jetting wouldn't be the cause.
When connected to a laptop it appears that everything is working normally when viewing the RPM/retard window. Is it possible the output to the 7AL2 would differ from what the laptop sees?
Any ideas what went wrong? Car ran fine with the 7AL2 set-up just days before.
Also, the LED on the side only indicates an error 11 stating no cam sync. Isn't there a way to clear this so I can observe the LED to make sure it is getting a signal from the distributor? Instructions show that it should blink for every input and flash steady after a few thousand RPM. Mine only blinks the code 11.
Let me know if you need an more info before I pull this out and put it back the way it was.
10-06-2003, 01:43 PM
Ok, lets start with the distributor first. Your starting and tach bouncing issues may be caused by incorrect rotor phasing between the rotor tip and the cap terminal. Check to make sure that when the ignition fires that the rotor is at the leading edge or directly over the terminal on the cap. Here is a link that shows you how to check for this.
Next, lets find out what is occuring with the 12 volts during cranking. As a test, remove the small gauge Red wire from the MSD and the Multi-Function Controller and hook them directly to Battery (+). Start the engine and see if the "no start" issue still occurs. To shut the engine off, you will need to remove the Red wires from the battery (+) terminal. If the engine starts fine, then you will need to measure the voltage on the ignition 12 volt wire that the two Red wires where hooked to. Make sure that during cranking that you have at least 7 volts during cranking. If you do not, you will need to find another 12 volt source for those wires.
As for the high rpm miss, that may also be casued by the rotor phasing issue. Check that first and then retest.
The "no cam-sync code can be cleared in the data editor of the multi-function controller by going to the "Alerts Per" selection and setting the "Alerts/Scan" to "0".
The default alerts/scan is set to 0 to not show any alerts until the user desires to change this feature to allow the alert mode of operation.
10-06-2003, 06:55 PM
the 12v wire leading to the box has 8.9 volts during cranking so that should be alright. I'll check the rotor phasing tomorrow and let you know what happens.
The alert/scan is set to zero, but the error code still shows up blinking on the box and pops up on the laptop. Should I try reloading the program in the MSD with a #1 in there then change back to zero and see if it resets itself.?
I'm not totally clear on the rotor phasing thing. If you move teh rotor using an MSD adjustable rotor wouldn't you just have to move teh distributor to compensate to keep the timing the same or isn't it affect teh timing?
10-07-2003, 10:10 PM
Try reloading the software to see if that corrects the issue. As for the rotor phasing, it will not affect your timing. The position of the trigger pickup in relation to the reluctor is what affects the timing.
10-12-2003, 08:43 PM
OK, had a lot of time for testing today. Rotor phasing looks good. On an Accel distributor the rotor and reluctor are on a fixed shaft with the advance plate below, so moving the advance plate dosn't affect the phasing.
Tried installing newest version of software and sending all data to box, didn't help. Tried adjusting the start and run retards to help with problems, nothing.
Finally unlocked distributor advance, set all retards in controller box to zero (run and start retards) and it still acted like it was starting against full advance.
During all this I noticed that the volt meter was always reading very low, around 10.5-11 volts with the motor running even though the alternator is working perfectly.
I unplugged the distributor lead from the 8979, unhooked the brown/white wire from the points input on the 7AL2 and hooked the distributor leads back to the 7AL2 (completely taking the 8979 out of the circuit) and the car started and ran perfectly. Volt meter then read correctly also even though the 8979 is still powered up but doesn't have the distributor wires or the brown/white wire going to the 7Al2
Any new ideas? This is getting very frustrating. New controller box and a new laptop to program it and I end up back with my old setup so I can race.
I bought this used from a person the bought it Nov. last year, but sent it in to MSD for checkup before selling it to me to make sure everything was good. He said he had no problems on his car.
10-13-2003, 12:08 PM
I have sent you a personal message.
10-15-2003, 05:19 AM
I have replied to your private message. Let me know if this works for you or I can give you my cell number.
10-15-2003, 09:34 AM
Got it and I will give you a call this afternoon.
10-16-2003, 12:25 PM
Maybe you can just post what you think might be wrong. You stated maybe a polarity problem. in which circuit? Between the distributor and 8979 box or between the 7AL2 and the coil.
10-16-2003, 04:38 PM
Shoot me your cell or a fax, I have been trying to call you.
10-17-2003, 03:39 PM
Check your PM's.I have both numbers
10-17-2003, 04:14 PM
I guess talking to you on the phone about this is just not an option. :) I am getting a machine on one and the second someone answered and said no one by that name was there. Here are two links that you need to follow, one of them is what is causing the trouble. One thing when locking out the distributor out the distributor it MUST be locked out in the full advanced position. I know you have the link on phasing but make sure this is being tested when the motor is running and you are using a non-adjustable timing light. As for the cam-sync, there is no way other then to install the cam-sync pick up to get rid of the code. That will be there until you have it hooked up. the polarity is the other thing you need to check, this too must be done while the motor is running and the timing light is a non-adjustable light. Keep in mind when you reverse the polarity to check it the most advanced reading is correct since you are using a digital box (opposite of the analog boxes). Here are the two links that cover the how's of both phasing and pickup's.
10-18-2003, 09:19 PM
So from reading the article about polarity I am wondering if that was the problem. When I switched from using the multifunction controller back to just the 7AL2 the timing stayed the same, which according to the article it shouldn't have done. It shows that with the analog box the timing would be more retarted than with the digital box. AM I correct in thinking this?
Would this also cause the symptoms I had with the volt meter in the car? I know it woud contribute to the hard starting and poor running.
I don't think it is anything with the phasing because it ran just as poorly with the distributor locked and the box controlling the timing and with the distributor unlocked and the box set at zero retard. unhooking the digital box and using just the 7Al2 ran perfectly immediately with no adjustments.
I'll test again after I race this weekend and let you know what's happening.
Ans the problem with my cell number was just my fat fingers typing in the wrong number. Sorry about that.
10-20-2003, 11:57 AM
It could cause it to run poorly if it is not right. Don't rule out the phasing issue, the problem sounds like the phasing more then polarity. The phasing will change with the addition of the timing control, and if it is off it might be enough to cause this to happen. Make sure that the timing was locked out in the advanced position like I had previously mentioned. Make sure the phasing is checked with the car running and a non-adjustable timing light. Let me know what is going on.
11-09-2003, 12:53 PM
OK, sorry about the long delay but I needed to finish the season with my old ignition setup and no time to play with the digital controller.
First question, when using the digital ignition controller should the polarity be when it is the most advanced? Seeing that I am still getting the spark from the 7AL2 I'm not sure which way would be correct. When hooked up the way I have it the timing stays the same with our without the digital box in the loop. If I change the polarity I have the same problems but the timing advances and I have to back it down. Both ways the same problems are present.
I drilled out the distributor cap and started the car with the 7AL2 and no multifunction controller hooked up. Rotor phasing looked perfect, just barely before, but almost perfectly pointed at the terminal. When I hooked in the multifunstion controller I once again had a problem with starting the motor. Would kill immediately when key was released. Once I finally got it started I checked the rotor phasing and it looked exactly like without the box hooked up (right at the termina, , but would occasionally jump to the the terminal before (looking at counter-clockwise). When this happens is when the tach bounces around erratically.
What would be causing this? Everything looks and works perfectly without the box hooked up , when attached it looks like the phasing thing is causing the problem, but what is causing the phasing problem that would only show up when the digital controller is hooked up and why would it only do it sperratically?
The warranty is running out very quickly on this (Nov 27th) so I would like to figure out something very soon.
I had the person that I bought the unit from send me the receipt and repair order in case it needed to be sent in for repair. It was originally sent to you on RO # 111552. Good unit :(aM) #124319.
Could there be something in the 7AL2's points input circiut? This is the only thing hooked up differently when using the digital controller.
Any other ideas?
Could it be something in the distributor dropping the mag signal occasionally? But why would it only do this with the digital controller and not without?
11-10-2003, 10:46 AM
The correct polarity is the most advance position when you use the digital box. Is the magnetic pick up adjustable in the Accell distributor(gap)? Make sure that the lead from the distributor to the MSD box is the one we supplied or an actual shielded cable. The jumping indicates a problem either with this cable picking up some noise due to routing etc. The fact it checked good that means it was run and tested with out any issues so I feel confident that the problem is not in the unit itself. Double/triple check that cable and make sure that the harness is not tied or loomed with ANY wires. If the air gap is adjustable move the air gap in and see if this helps. On the polarity, the most advanced being correct, hook the wires up in this position and reset your timing. Hook up your lap-top and watch the RPM file(two gauges on the screen) and see if any retard is popping up on the dial.
11-10-2003, 04:19 PM
When I bought this box it did not come with the cable. The Accel distributor has a 2-wire quick disconnect that had 2 wires coming out the end that were screwed to the 7AL2 input terminals. I bought an MSD end kit and attached an MSD end to these wires. So actually there are now 2 places that the wire has a quick connect, the original Accel connection and the MSD connection at the digital box. Is it possible that this is causing all the problems and what should I do differently ? I can't really do anything about the Accel disconnect unless I clip off the connector and wire in the MSD end. What is different about the lead that is supplied? Can I somehow shield the cable that I have now? The whole wire from distributor to box is only about 1 foot long. It goes from the distributor directly backwards through the firewall and over about 7 inches to the box.
Airgap on this distributor is not adjustable. Like I said it's an older Accel magentic distributor, model 43000A. It doesn't look like any of the current distributors. The distributor body has a plate with 8 steel "points" facing towards the center shaft. The shaft has a wheel attached the has 8 steel "points' that face the points of the bodies ring. These are spaced so the all line up at the same time when turned. So at every terminal all 8 points line up. Under this is what appears to be a wound coil. I think I'll look at replacing this also, but that shouldn't be the problem seeing that it runs good with the 7AL2.
I changed polarity, set the timing and when revving the motor I never see any retards activate. Right now everything is set to zero.
Thanks again for the quick reponses on this problem.
11-12-2003, 11:07 AM
If that cable is just two wires routed from the box to distributor that could be causing this problem. Send me a personal message and I will send you out a shielded harness and see if this helps settle things down. Give me an exact length and I will make a short harness up for you. Another thing where these wires are going through the fire wall are they going through with any other wires, coil wires, coil wire(spark plug), fan wires etc?
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