May have found rough idle cause (with pics)
 

Ive been fighting a rough idle for a while, fixed various vacuum issues, fuel spider, etc. Just to cover all my bases I lined the timing mark up to the notch (#1 at TDC I think), took my distributor cap off, and found the button pointing at about the 10 o'clock position (see photo). My tech manual said it should be more like at the 6 o'clock position. Am I 180 degrees out?

Thanks as always.

Being 180 out I think you would see more than just a rough idle. You sure you have the right timing mark on harmonic lined up?

I only have one timing mark (photo) and not the teeth. If it was on the exhaust stroke it would be 180 out, right? If thats the case it should be pointing at 12:00?

After reading all night on here, pretty much decided it cant be 180 out or it wouldnt run good at all. Im gonna rotate the crank around one more revolution and see where it points.

I changed the distributor cap and button, wondering if that could have thrown the timimg off a little.

Well, rotated the engine around 180 and sure enough the rotor pin is where it should be. Gonna put it back together and do a compression check next. Ugh. I'm about to sell this thing.

Have you cleaned the egr valve yet

yep, it's brand new. took it off and put a screen on.

just did a compression check. All cylinders 135-150 psi, except #5, which was 90 psi. :( Squirted some oil in, no change. Guess I found my rough idle. What does that mean mechanically?

Is it giving you any codes? SES light on? I had a rough idle and it ended up being a bent valve. I had replaced cap, rotor, plugs, wires, spider injector, egr valve screen, and cleaned maf and pcv valve. None of that worked. I should have got the compression test first...

No SES code, replaced everything you did, and should have done the test first. However the spider was toast and it has smoothed out some, but I guess I need to research a positive pressure test to pinpoint the problem.

Thanks guys.