I started discussing my problems here . But they seem to have changed a little so I'm starting a new thread. Just to recap: car is an '89 305/TBI/auto. Full tune-up performed, also new EGR.
I scrutinized the vaccum system and found a bad line on the back of the manifold, thought my problems were solved. I was wrong, but it is a little better.
On the test drive I decided to put the transmission in "1" and "2" so I could hold a gear and listen to the motor throughout the RPM range. The tach reads high so that was of no use. I made my observations based on MPH. FYI The car did not have a tach when I bought it, so I installed one from an older Z/28 crossfire injection car. I don't know if that has anything with it reading high or not, it may just be a POS.
So the car runs like I think it should above 30-35 mph in 2nd, and above ~15 mph if held in 1st. It's strong and responsive at any throttle setting, feels smooth and has a good clean exhaust note. In fact the higher the revs the better it seems to run.
It cruises at a steady throttle setting well, it also idles well. It may be possible for it to idle/cruise better, but I'm pretty satified with it. But when I push the throttle any amount between idle and whatever RPM 30-35 mph in 2nd is, there is a noticable bog and and the motor runs a little rough as it accelerates until it reaches a higher RPM
Could the IAC or MAP sensor be playing a role in this?
My only other thought is maybey the ECM is also seeing too high of an RPM and advancing the timing too much at low RPM's
Any thoughts?

 

Run the car in the dark with the hood up. Search around for a spark leak.

Mine did similar to that once. I had the motor just about all apart, changed n checked every sensor. Ended up the coil was leaking spark. Went through 3 coils but they kept leaking.
Then I did a full tune up and it fixed the problem. Even though the wires were newer and its wasn't time for a tune up. Once I did a full fresh tune up, I had my original coil back on and no spark leakage.

 

Thanks, I'll give the coil a good looking over. The wires/plugs/cap/rotor are all brand new, so I'm pretty sure they can be ruled out.

 

Ya find anything out yet???

 

Had to wait for it to get dark last night, we're a little behind most of you Could not see any arcing. I'll have more time tonight so I'll read out all the ignition compnents I can. It's just frustrating because the car is so close to running perfect. If I don't find it soon I may have to take a step I never have...take it to a mechanic

 

I read out the distributor pick-up and it read good, but on closer inspection the whole assembly seemed to be severly corroded, and the wires were dry rotted and cracked, module was looking a little suspect as well. Long story short:
I found a good deal and replaced the entire distibutor for $20 more than just a pick up and module would have cost. Now the car run much snappier, starts quicker, and sounds much better. The only troubling thing is that there is a little more vibration. The distributor that I bought looked a little different than what came out. Here is what I installed


The one I removed had the pick-up enclosed in a copper ring. I couldn't see how that ring could be incorporated on the new dist. Is there anything missing from the new one? All I added to the assembly in the picture was the cap and rotor.

 

The manual didn't help at all, first step told me to remove three screws. Well there weren't any screws holding the original dist pick-up together. In fact it didn't seem servicable at all. However the re-man unit does have the screws.
When I installed the new dist I lined the pulley mark up with 0* TDC, the rotor up with #1 spark plug terminal. It fired first time and I was able to set the timing to 0*. I'm paranoid now because it went to easy. Considering that it fired right away and I was able to time it, is there any chance it could be 180* out, or off in some other way.

 

Due to change in question I started a new thread HERE