Msd 6al

[TTop GT]

on my 87 5.0....

i got a msd box and hooked it up, when i fire the car up, it runs badass... but after a short drive(less than 5 mins.), it starts idoling erraticlly(spelling sucks), it almost sounds like it has a cam... but it just runs rough... if i turn on my headlights, it smoothes out and runs good. - if it let it cool off and try it again, the scenerio repeats.

do i need plugs with a different heat range(i have bosch platnum [the regular ones, not the 20 prong gimmik ones] stock replacements currently)?

is it possible that i need to re gap the plugs differently(.050 currently)? -the msd book says .060, i wouldnt think smaller would have any adverse affects though


thanks,

[maveRick]

Grounding-short in head lamps? (unplug lamps and test)

also,

What do the plugs indicate - rich? lean? just right?


'just shooting in the dark, here.

[Guffinator]

So I'm assuming from your story that all was well BEFORE the MSD install?

Shooting from the hip....

This sounds EXACTLY like a cracked coil that I had once. Would run fine till the coil heated up....then it would miss and sputter. Took me forever to find that issue.

[TTop GT]

the only thing i changed, was the fact that i added the msd box... thats it

the car runs excellent as soon as i unplug the msd box... i know the box works because tommie vaughn tested it right in front of me, it worked great and didnt mis a beat

the coil and all the other stuff works great, untill i plug in the box

[Wild Stallion]

You have to remember that the MSD stands for Multiple Spark Discharge, The problem sounds like you have a weak coil. Instead of firing once per cylinder, (your coil is handling that ok) it now has twenty or so sparks per cylinder per revolution. Try a different coil and see if it persists.

[TTop GT]

im using an msd blaster tfi coil i fugured thated be good enough