Swartik, I have not had the engine scanned yet, just reading the codes with a cheap reader.

 

As Kyle and I both mentioned, you'll need to find out what the CMP retard reading is.

If you go to a good shop, they should have a scan tool capable of viewing it. Might want to ask them if they know what it is, and how to adjust it, before you sign up for ANY work. Some of our members say their local GM dealer didn't have a clue what it was. Don't let them talk you into replacing any parts, the adjustment is all you need. To check and adjust it should be under an hour of labor.

If it's ~27 degrees positive or negative, the distributor is off one tooth. The adjustment will allow for ~14 degrees of total adjustment, (7 each way). If they tell you there isn't enough adjustment to get it within spec, leave. Stop by the auto parts store on your way home. Pick up one of these and we'll explain what to do with it: http://www.summitracing.com/parts/mrg-1009 Or, if you want, you can modify the original distributor hold down. After installing the new bracket, or modifying the original bracket, the distributor becomes fully adjustable.

 

Well thank you gentlemen for the insights. I talked to the shop today, and was honest when I told them I wanted them to diagnose only, charge me their fair rate, and I would (I hope) do the repairs. It's a project truck. They said sure, a scan is 90 bucks. But now I am learning the fine points of what to ask and expect.

At this point, I have sunk about 160 bucks into my 750 dollar blazer, so it is not exactly a money pit yet. I just have to keep telling myself "I bought this thing as a fun project." So far it has been fun and educational.

 

You can modify the bracket yourself, (if it's necessary) it's not difficult at all, but the scan tool will need to be connected when making the actual adjustment to the distributor. I'd flat out ask these guys if they know what camshaft retard is, and if they know how to adjust it, if not, find a shop that does. If the only DTC is P1345, that's all they're going to find. No sense spending $90 if they aren't going to tell you what you need to know.

 

Well I finally got the blazer back, it had been at the shop for a week. Success! No more codes. The mechanic said the distributor was off a tooth. I am kind of surprised at that, since I became quite familiar with the process, and did the trial and error procedure noted earlier in the thread. But I am a rookie so who knows. And as he mentioned (and as I learned here) the vehicle needed to be scanned anyway, so it was not a wasted trip. And the rate was very reasonable. So the project is back on track. Now to figure out why the heater decided to quit working. rats.

Thank you gentlemen for the education!

 

Glad they got the SES light off, and no DTC in memory, BUT, did they check and adjust camshaft retard? That's part of the job when you remove an EDI distributor. Having it meshed correctly with the camshaft, (no SES light) is not close enough. That's the "rough adjustment", and it means camshaft retard is "in the ball park", but it's a big ball park, ~54 degrees. Kinda like sex: being in the same room is a start, but it isn't close enough

 

The mechanic assured me he set the retard, and I suppose I have no reason not to believe him. It was my first time using these guys for anything, and they seem pretty honest. And of course, I went in armed with knowledge garnered from the generous guys on the blazer forum.

If I go the shop again, and I probably will, I will try to take a picture of the interior. It dates to 1950 and really looks like it, A grease pit, a lift, and a bunch of old stuff. Like Goober's shop on the Andy Griffith show.