Ignition + CEL issues
#1
03-04-2015, 11:01 PM
Ignition + CEL issues
Last while, trucks been stumbling or downright dying under 1500 rpm, and would spin endlessly in the mornings until boosted. Check fuel- 50psi prime + run. Check alternator- 13.9 volts. Check battery- 12.8 engine off.
On a whim, I switch from the MSD to the factory coil. Fires right off, no stumbling. So now I have to figure out if the box is bad or the coil. Only started doing it when it's been cold. (Coil?). Also, when it was stumbling and trying to die, I was getting a pulse noise in the front speakers, maybe fuel injector feedback? Or it may even be the injectors themselves I'm hearing.
Also, the CEL is on, but there's no fault codes and only a 0442 pending....last I checked, pending does not set a light? With that said, I was getting random misfires on the MSD, but they went away when I switched to stock ignition...again points to ignition issue?
Also, the transmission gear display goes bonkers every now and then, with the outline square going all over the place when I'm not even touching the shifter.
Lastly, it was backfiring through the intake real bad under accel with the MSD....it went about halfway away on stock ignition. Granted the SCT has a ton of advance rolled in the computer, it shouldn't be enough to be popping into the manifold. I'm not getting any can sync faults, so I don't think the timing chain is too stretched, but I am at 171K miles.
On a whim, I switch from the MSD to the factory coil. Fires right off, no stumbling. So now I have to figure out if the box is bad or the coil. Only started doing it when it's been cold. (Coil?). Also, when it was stumbling and trying to die, I was getting a pulse noise in the front speakers, maybe fuel injector feedback? Or it may even be the injectors themselves I'm hearing.
Also, the CEL is on, but there's no fault codes and only a 0442 pending....last I checked, pending does not set a light? With that said, I was getting random misfires on the MSD, but they went away when I switched to stock ignition...again points to ignition issue?
Also, the transmission gear display goes bonkers every now and then, with the outline square going all over the place when I'm not even touching the shifter.
Lastly, it was backfiring through the intake real bad under accel with the MSD....it went about halfway away on stock ignition. Granted the SCT has a ton of advance rolled in the computer, it shouldn't be enough to be popping into the manifold. I'm not getting any can sync faults, so I don't think the timing chain is too stretched, but I am at 171K miles.
#2
03-05-2015, 12:08 AM
Champion
Do remember that MSD also stands for Makes Spark Disappear ...
On coils for the Thunderbird SC, MSDs are known to not hold up like the Motorcraft, and even at 20+ pounds boost, all it takes is a step colder plug and tightening the gap up a bit for the OEM coils to work great. I'd stay with a new OEM coil instead.
RwP
On coils for the Thunderbird SC, MSDs are known to not hold up like the Motorcraft, and even at 20+ pounds boost, all it takes is a step colder plug and tightening the gap up a bit for the OEM coils to work great. I'd stay with a new OEM coil instead.
RwP
