Pulling Heads for Exhaust

Just to clarify, the EST module is the square black box on the firewall, correct?

About 1/3 the size of a pcm.

About 1/3 the size of a pcm.

I did some testing today concerning codes 42 and 43. I made the computer throw code 42 by disconnecting the EST module. And 43 has been coming in on its own. I went through the testing procedures for both codes. 42 of course should be fine. It's final outcome was a bad connection or faulty ignition module. I did the testing with the EST module unplugged. So of course that conclusion came about.

With testing for code 43, I got slightly stuck at the last step. After using a 1.5V battery to test for a voltage drop on the tach terminal, which there was, I came to "Is rotating pole piece still magnetized?" I don't know if I answered the question correctly. If yes, then I should check the resistance of the coil. I did that and it is within spec. If no, then "replace pole piece and shaft assembly." Does that mean basically, replace the distributor? The coil, ignition module, and ignition coil are all new within a year. I've tested them and they are good. Do I need a new distributor pole and assembly?? I assume it should becoming magnetized and is not.

I did some testing today concerning codes 42 and 43. I made the computer throw code 42 by disconnecting the EST module. And 43 has been coming in on its own. I went through the testing procedures for both codes. 42 of course should be fine. It's final outcome was a bad connection or faulty ignition module. I did the testing with the EST module unplugged. So of course that conclusion came about.

With testing for code 43, I got slightly stuck at the last step. After using a 1.5V battery to test for a voltage drop on the tach terminal, which there was, I came to "Is rotating pole piece still magnetized?" I don't know if I answered the question correctly. If yes, then I should check the resistance of the coil. I did that and it is within spec. If no, then "replace pole piece and shaft assembly." Does that mean basically, replace the distributor? The coil, ignition module, and ignition coil are all new within a year. I've tested them and they are good. Do I need a new distributor pole and assembly?? I assume it should becoming magnetized and is not.

The dist pickup coil can be replaced,
But you have to remove dist and dist gear and pull dist shaft out of dist.
Just make sure the dist shaft does not have side play.

The dist pickup coil can be replaced,
But you have to remove dist and dist gear and pull dist shaft out of dist.
Just make sure the dist shaft does not have side play.

I replaced the dist coil this past summer. I checked it's resistance yesterday and it was within spec. Is the assembly bad? According to the testing flowchart, that's what I would assume for a code 43.

I replaced the dist coil this past summer. I checked it's resistance yesterday and it was within spec. Is the assembly bad? According to the testing flowchart, that's what I would assume for a code 43.

Code 43 pertains to knock sensors and connections and wiring.

What kind of info/repair information are you using?

Code 43 pertains to knock sensors and connections and wiring.

What kind of info/repair information are you using?

You're absolutely right! I meant to say I did the testing for code 43 and that took me to the 'ignition system check' flow chart. That's where I got the magnetic conclusion.

You're absolutely right! I meant to say I did the testing for code 43 and that took me to the 'ignition system check' flow chart. That's where I got the magnetic conclusion.

What kind of info/repair information are you using?

What kind of info/repair information are you using?

I'm using the Chevy service manual for my truck.