MSD 6010 now causing horrible missfiring?! WTF?
11-27-2008, 02:43 PM
#1
MSD 6010 now causing horrible missfiring?! WTF? I had this car running beautifully! It sat for about 2 weeks in my car trailer without me driving it so decided to start it up a little while ago and it started missing horrible and wouldnt run at all. I waited until today to start working on it. I ran the engine for about 30 seconds at 2800rpm or so i know its not good but then i shut it off and felt the header pipes. 1 was cold as ice, 3 was cold as ice, 5 was hot as could be 7 was hot as could be. 2 was cool, 4 was cool, 6 was warm, 8 was hot but not as hot as 5 and 7.
My wideband was of course showing it was over 22:1 lean with it running so it was really no help. I upped the fuel at idle - nothing. Upped the primary jet size by 6 sizes, nothing (i have adjust-a-jets), uppsed the rear jet sizes by 4 sizes, no different. Fuel pressure is 7.5 psi what it alwasy is. Intake is a singple plane so i have ruled out all possible fuel issues.
I pulled the valve covers, cranked the engine while looking everything over. Oil shooting out but nothing abnormal. No loose rockers, nothing to indicate bent pushrods. I unplugged my MAP sensor just to make sure it didnt go bad not that it would adjust my timing more than 9degrees even if it did. I check every ground on my engine. They are all fine. Battery is perfectly fine, alternater makes 14.4v when the engine runs so thats fine. I checked the entire harness over, there was nothing wrong with it.
This leaves only 3 possibilities to me. My MSD box has somehow gone bad, my cam sensor has somehow gone bad, or my crank sensor has some how gone bad. I suppose my coils could have gone bad but they are from an 2002 (i think) silverado and i couldt see 1 going bad but not all of the cylinders im having go wrong. I'm heading back out ot plug my laptop into the msd to see if somehow the tune went crazy with the cold weather we've been having.
Any ideas guys?
My wideband was of course showing it was over 22:1 lean with it running so it was really no help. I upped the fuel at idle - nothing. Upped the primary jet size by 6 sizes, nothing (i have adjust-a-jets), uppsed the rear jet sizes by 4 sizes, no different. Fuel pressure is 7.5 psi what it alwasy is. Intake is a singple plane so i have ruled out all possible fuel issues.
I pulled the valve covers, cranked the engine while looking everything over. Oil shooting out but nothing abnormal. No loose rockers, nothing to indicate bent pushrods. I unplugged my MAP sensor just to make sure it didnt go bad not that it would adjust my timing more than 9degrees even if it did. I check every ground on my engine. They are all fine. Battery is perfectly fine, alternater makes 14.4v when the engine runs so thats fine. I checked the entire harness over, there was nothing wrong with it.
This leaves only 3 possibilities to me. My MSD box has somehow gone bad, my cam sensor has somehow gone bad, or my crank sensor has some how gone bad. I suppose my coils could have gone bad but they are from an 2002 (i think) silverado and i couldt see 1 going bad but not all of the cylinders im having go wrong. I'm heading back out ot plug my laptop into the msd to see if somehow the tune went crazy with the cold weather we've been having.
Any ideas guys?
Last edited by Shawn MacAnanny; 11-29-2008 at 11:53 AM.
11-27-2008, 02:54 PM
#3
I just put my laptop on it, MAP is working fine, timing is right, ran it for a little longer but the front 4 cylinders are still cold as can be. The engine does have coolant in it, did not freeze, it has 17 hours on it since i did the swap according to the MSD box. I am completely out of ideas. Why would the MSD not be firing the 1,2,3,4 cylinders? Could i have a bad cam sensor?
11-27-2008, 02:58 PM
#5
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Bad cam or crank sensor should affect the operation of all 8 cylinders. Have you checked the power to the coils and then the switched output/ground through the box?
11-27-2008, 03:41 PM
#7
What would a faulty crank sensor cause? I just cant see the carburetor causing all of these problems. I've tried leaning it out, richiening it up quite a bit each way with no results. I should not be able to put my hand on 4 of my header primaries and then lose finger prints on the other 4. I'm going to get a set of plugs and see if that helps. The one plug did have slight oil on the threads but i dont think thats the problem. It just doesnt make sense that nothing changed and my engine went from PERFECT to not running.
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11-27-2008, 05:09 PM
#9
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When I first got mine running it was missing on 2 or 3 cylinders. I tried everything from fuel, plugs, coils wires and grounds, finally changed the crank sensor and it fixed it.
My plugs looked brand new on the cylinders it wasn't firing, I would try a new set of plugs and a sensor.
My plugs looked brand new on the cylinders it wasn't firing, I would try a new set of plugs and a sensor.
11-28-2008, 01:03 PM
#11
Check each plug to see if they are firing. An inductive timing light might work, or the old tried and true pull the plug wire and watch the jump to ground.
Pulling the plugs and inspecting them is not a bad idea. maybe something fouled.
Pulling the plugs and inspecting them is not a bad idea. maybe something fouled.
11-28-2008, 03:05 PM
#12
Hey yeah the timing light is a great idea! I didnt even think about it. If they are firing then maybe ill switcha plugs. They were 'black ish' but i wouldnt consider them non-firable at all. I've seen way worse plugs on a much weaker ignition firing just fine. And for 4 to go at once just doesnt make sense.
I do know tha ti have them gapped wrong, TR6s gapped at .050. For some reason i thought i was putting in TR55s when i put in the TR6s.
I do know tha ti have them gapped wrong, TR6s gapped at .050. For some reason i thought i was putting in TR55s when i put in the TR6s.
11-28-2008, 05:28 PM
#14
actually i had a rivet (one of the four on the box) break when i was drilling the holes when i mounted it, but it was drawn tight immediately by the bolt i put through so i couldnt imagine it was damp. Its never seen rain or even fog. It always been kept in a sealed 28ft enclosed trailer. No moisture but whats in the air ever gets to it.
11-29-2008, 07:01 AM
#15
just curious-are you #ing the cyls correctly-pass side is 1357, d/s is 2468
it would make sense if one of the cyl banks was out due to the way its wired
if its cyls on both sides, odd and even, almost makes me wonder if its in some kind of retard or rev limit mode, canceling out cyls???????????
i know sitting in an enclosed trailer, you can build up some moisture, depending on where you live, isolate grounds, etc
it would make sense if one of the cyl banks was out due to the way its wired
if its cyls on both sides, odd and even, almost makes me wonder if its in some kind of retard or rev limit mode, canceling out cyls???????????
i know sitting in an enclosed trailer, you can build up some moisture, depending on where you live, isolate grounds, etc
11-29-2008, 11:08 AM
#16
Um no i put driverside 1357 LMAO are you serious? I thought thats how it went. I didnt change it ever though. I've driven this car hundreds of miles like this. It has 18 hours on it according to the msd box.
I thought that too actually and i set the high rev limit to 2000rpm just to see if it still worked and it did limit it but it sounds to me more like its firing cylinders wrong. I'm not getting any intake backfires though.
I thought that too actually and i set the high rev limit to 2000rpm just to see if it still worked and it did limit it but it sounds to me more like its firing cylinders wrong. I'm not getting any intake backfires though.
11-29-2008, 11:49 AM
#17
I tried swapping the connectors but 2468 are too close to the crank sensor to reach the driver side so i just left them the way they were. I replaced all 8 spark plugs with NGK TR55s gapped them to .055. The plugs i removed were black but looked fireable to me. as i suspected the front 4 cylinders were wet with fuel the others dry but just as black.
I fired it up and it came to life instantly. RUNS AWESOME! I guess with all the 18 hours of run time and hudreds of fuel adjustments i managed to foul the plugs up pretty badly and eventually they just stopped running. She sure sounds nice though. Thanks guys!
I fired it up and it came to life instantly. RUNS AWESOME! I guess with all the 18 hours of run time and hudreds of fuel adjustments i managed to foul the plugs up pretty badly and eventually they just stopped running. She sure sounds nice though. Thanks guys!
11-29-2008, 06:51 PM
#19
Haha eventually. I'm still tuning all the little bugs out. I think finding these plugs were bad is going to help me immensly now tuning it on the road. It had a couple stumbles down low at part throttle and what not so hopefully this will help me fix them. Then after that i need to order my 30" 315 ET street radials so i can get some traction. I just have 225 street tires on it now since i picked up a rock in my slicks.
11-30-2008, 06:57 AM
#20
glad you got it ironed out-i think the tr-55's dont have an extended tip, why i like the tr-5 or 6-i would close up the gap to .035, esp with a carb-fi can monitor fuel a little better, the carb is going to be a little richer at times
i ran thru a bunch of plugs at first, pump cams, powervalves, hi sp a/b's, etc
everything i knew about boosted s/b's proved diff on a boosted LS style motor, but the driveability now is super
i ran thru a bunch of plugs at first, pump cams, powervalves, hi sp a/b's, etc
everything i knew about boosted s/b's proved diff on a boosted LS style motor, but the driveability now is super