My MSD digital 6+ took a crap, so I sent it away to get fixed.

I thought I would atleast drive the car while waiting for the ignition box to get fixed.

I looped the box out, so it would run, but now it runs very rough.
I unplugged the EST and the engine runs way better! But the initial timing was at 60 degrees advanced! I did NOT change anything in the dizzy to change the timing.

I have no codes.

So I turned down the timing to 10,(which it was before).

Now the engine won't start, but it will runs with the EST unplugged.
I have a spare ECM and it didn't make a difference

Is there a ESC module?
Would a pick-up in the dizzy do this? (I have a pro-billet MSD dizzy)
I also changed the ignitoin module too

 

Make sure the outer ring on your balancer hasnt spun on the inner hub.

 

How do you check that?

 

What would make the timing go really advanced?

Does the knock sensor do that or is there a timing module?

 

You'll have to look at a new balancer and compare the crank keyway postion to the outer timing mark.

 

I got a code 33(MAP sensor)

IF I test it the way these guys want
http://www.chevythunder.com/map_code_33.htm
Then I should have a faulty MAP sensor (sensor unplugged with ignition on, I get less than 1 volt.

But, if I test the MAP sensor while it is plugged in, it works fine. 4+ volts, then if I apply vacuum, the voltage goes down.

 

If it was the MAP sensor, would it make it run that bad?