msd 6012 hickups w vid
07-19-2014, 11:43 AM
#1
msd 6012 hickups w vid took it to the track a few weeks ago. made my first pass and everything worked perfect.
went back to the pits and gave it 2 degrees more timing and brought the timing in earlier. I also bumped the rev limiter to 7,500 from 7100 so I could bump my shift points from 6,800 to 7,200.
since that flash it started doing this. I changed it all back to the way it was before and it's still doing it. voltage is a hair low in the 12.8-13.2 range but in the past I've gone WOT with no alternator at all and it ran clean
in idle/park it revs clean to 7k. put it under load and it starts shitting. where should I start?
went back to the pits and gave it 2 degrees more timing and brought the timing in earlier. I also bumped the rev limiter to 7,500 from 7100 so I could bump my shift points from 6,800 to 7,200.
since that flash it started doing this. I changed it all back to the way it was before and it's still doing it. voltage is a hair low in the 12.8-13.2 range but in the past I've gone WOT with no alternator at all and it ran clean
in idle/park it revs clean to 7k. put it under load and it starts shitting. where should I start?
07-19-2014, 01:10 PM
#2
Sure you don't have a fuel issue? Maybe a pump going bad or clogged filter? Pull plugs and check them too. Be careful about assuming it is the box and not something else.
07-19-2014, 01:44 PM
#3
afr shows 12.5-13.0 when this is happening. you can see in the video that it will bounce 6k for a bit, then catch on and rev to the 7200 rev limiter. it revs perfect from neutral/park. it made it's fastest pass just before the computer flash. fuel pressure is a bit high at 8psi but my regulator wont come down anymore.
07-19-2014, 03:32 PM
#4
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That doesn't look like a box issue or voltage issue but just to try it make a file with the exact same tune and re-flash it and take the truck out again if it's a bug with the flash maybe the new flash will clear it. If it was a voltage or ground issue I think it would do more than just limit it at 6000 for a second. I personally think it's a fuel issue as said above maybe a stopped up fuel filter. Anyway keep us informed I love this kind of stuff.
07-20-2014, 02:28 PM
#6
floats are perfect and I have 8psi at the rail which is actually a tad high. afr reads perfect. I dont think I'm running out of fuel. I tried keeping the wideband in the video but I guess I suck at multitasking. checking the filters is a wet stinky job lol
I've tried reflashing it. I put it back to the exact tune that it ran great 1 pass before and it still does it. i'll try again.
I've tried reflashing it. I put it back to the exact tune that it ran great 1 pass before and it still does it. i'll try again.
07-20-2014, 04:17 PM
#7
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Well since the only thing we deal with is usually fuel probs, electric probs and you have almost ruled out fuel ( couldn't see wideband while it was "skipping") try to jiggle the harness around the power and ground areas and alternator connections even try jarring the box maybe tap it with a screwdriver while it's running and see if flutters then. Also I couldn't see the alt gauge so couldn't see if it was cutting out under high load some alternators will pop the inside stuff under high rpm, I had to replace two of them from oriellys cause they kept giving me rebuilt 175 amp alts instead of the factory 105 amp that's suppose to be there. You could always unplug the alt to see if that's causing the issue....
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08-12-2014, 12:47 PM
#9
how is MSD on wiring harness problems?
i had a guy named guy (lol) ride with me watching the scanner and everything looked perfectly fine. the motor was jumping and bucking everywhere with the ignition cutting out but the scanner looked normal as could be (why doesnt MSD have a recorder on the scanner to help us?).
i replaced the crank position sensor as a last guess before sending the box back to MSD. i made sure that the + & - was strong and they were. disconnected plugs from coil packs and cam sensor to inspect connections. everything looked normal.between each plug/wire jiggle. i was restarting the truck n a last ditch effort i reached inside of the main harness to the MSD box and just yanked a hand full of wires out of the loom to see if anything stood out (krimped wire, melted wire, whatever stood out). after a very quick inspection everything looked normal so i shoved the wires back into the loom. I started the truck to drive into the garage and leave it for another month and immediately noticed the idle was cleaned up.
took it for a test drive and was smiling from ear to ear! clean ignition all the way to 7,800 rpm (by accident). now i'm literally afraid to touch the wiring harness and revert it back to the old problem...and i am afraid to spray this engine with some mystery wire/ignition problem. one little hickup like i was having could cost a lot of money if on nitrous.
in the past, has anyone been able to send a harness to MSD without taking it from behind? i'm glad it's running good again, but i wouldnt call it fixed by any means. i want a harness with a clean bill of health.
i had a guy named guy (lol) ride with me watching the scanner and everything looked perfectly fine. the motor was jumping and bucking everywhere with the ignition cutting out but the scanner looked normal as could be (why doesnt MSD have a recorder on the scanner to help us?).
i replaced the crank position sensor as a last guess before sending the box back to MSD. i made sure that the + & - was strong and they were. disconnected plugs from coil packs and cam sensor to inspect connections. everything looked normal.between each plug/wire jiggle. i was restarting the truck n a last ditch effort i reached inside of the main harness to the MSD box and just yanked a hand full of wires out of the loom to see if anything stood out (krimped wire, melted wire, whatever stood out). after a very quick inspection everything looked normal so i shoved the wires back into the loom. I started the truck to drive into the garage and leave it for another month and immediately noticed the idle was cleaned up.
took it for a test drive and was smiling from ear to ear! clean ignition all the way to 7,800 rpm (by accident). now i'm literally afraid to touch the wiring harness and revert it back to the old problem...and i am afraid to spray this engine with some mystery wire/ignition problem. one little hickup like i was having could cost a lot of money if on nitrous.
in the past, has anyone been able to send a harness to MSD without taking it from behind? i'm glad it's running good again, but i wouldnt call it fixed by any means. i want a harness with a clean bill of health.
it's pretty mild at idle for a dual dynomax bullet setup (longest bullets they make). but damn does it bark at WOT
08-15-2014, 06:53 PM
#16
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