Done the search in the archive and read all found threads on the issue. Tried the recomendations and still no luck.

Here is what I have. 1990 Vert. New engine. All stock. No vacum leaks. Good injectors o rings and gromets. Excellent compression, Like I said, New rebuild). Got a friend to play with the AFM and the car will idle a bit better. Bought a remanufactured AFM and another used u=one and still have same problem.
At one point I removed the entire intake system and installed a 6 port racing beat intake and holley and the engine ran smoothly.
I am very frustrated and tire of looking at the car. I am sure the owner is even more frustrated.
Can some one please help me out.

 

Have you tried verifying your fuel and ignition?

 

how "new" is the engine?

also check what was previously posted.

 

Yes!

 

All the seals are new. The housings are in good shape. The irons met the specs. Done twenty some engines before, with no problems, well actually, I was drunnk once doing an engine and tried to put a 13B shaft ina 12A, (lol).
The engine with a carburator ran smoothly, once I hooked all the stock parts is when it acts up.

 

could it possibly be low compression due to new seals on used housings?

tried push starting it?

 

I should have name the tread bad iddle! I can get the car started. It just does not iddle right. With the AFM connected it shoots up to the 3-4,000 rage on the RPMs, without the AFM I had to play with the pedal.

 

Vacuum leak?

 

I am removing everything this weekend and i am going to go through it all and try to anrrow this down.

 

Racing beat intake is the exhaust manifold? Just asking...

 

It has the stock manifold. In an effort to avoid taking the engine apart, I removed the stock intake and put a Racing Beat intake with a Holley on the engine to test if it was a good engine. GOt crank on first attempt and got it to stay running at iddle, smoothly for a while, two days in a row.
Put everything back together. Checked for possible vacum leaks. Replaced hose that look close to brittle. Everything look good and I was hoping I would not have any more issues. Two months later, I am still chasing a ghost.

 

Check the TPS and Bac

 

I thnk I have already, but to tell you the thruth I am not even sure at this point. Wll check it today, Thanks!

 

Let us know if you get it running.

 

check and adjust the TPS
check for vacuum leaks with the engine running with carb cleaner(i know you said it has no leaks but check again!)
adjust the variable resistor(on the RF strut tower) by turning it clockwise
try swapping the AFM with another unit(i don't trust reman AFMs)
check timing to see if it is even remotely close
check fuel pressure and/or voltage at your fuel pump

 

Awesome! Im starting to see more options and checks that I have not seeing. Will try all this today. Thanks!