|Originally posted by pdemondo:|
If the timing is way off, wouldn't it also not run properly when I have the OBD connector pins a and b shorted?
Not necessarily. When the jumper is not
in place, the ECM is advancing the ignition timing by a considerable margin. With the jumper in place, it's possible the engine runs smoother because the ignition isn't as far advanced.
Keep in mind, if the outer ring of the harmonic balancer has spun (which isn't
uncommon with a 25 year old balancer), the ignition timing will be incorrect (after using a timing light) as the timing marks will be in the wrong location relative to the crankshaft.
It happens to the best of us... including me.
More information HERE
[This message has been edited by Patrick (edited 12-27-2014).]