Check engine light, but no check code error displayed
 

I don't want to make this post too confusing but here is the situation.

I bought a 89 gxl an and put my 88 gxl na motor into it (block only). All electronics emissions intake, MOP plugged in, ports all functional, from the 89 bolted to it.
(The 88 motor was running great in my car before the crash, avg 17 mpg)
The car is stock, other than the 88 block.
Car idles well and tps adjusted recently

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Problems I am having:
> lack of top end power
> 14 mpg
> random check engine light
> no error codes listed
> Hard start always
> misfire feeling in 5th gear around 2.7k rpm on the freeway.
>Fuel smell inside the car, when I drive hard.
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Questions:
> Why is there no error code being displayed? the check engine light showed up when i was driving in 5th gear on the freeway. i pulled off and the light remained on. I turned the key off and jumpered the test terminal, turned the key to on and no CEL was listed. The check engine light does not come on often. It also flickered once when I tried to rev past 7.5krpm.

>Lack of top end power, i know this because i ran this motor in my daily driven 88, and top end power was good. But now in this 89 the top end power sucks, will just drop off at 5.5k. My current guess is either fuel related, spark timing, or that it is in limp mode. The lack of top end power happens even if the check engine light is off.
(I have a safc1 and if i go full lean or rich on top end, it has little effect. safc does show a clean tps reading)

> I am getting a AEM wideband soon and will have a better handle on afr.

I will leave it at that for now, and feed more info based on questions

view picture then video
http://www.youtube.com/watch?v=e-KTQ...ature=youtu.be

Mine flickered when the TPS was on it's way out. I could adjust the TPS where it needed to be but checked it with a multimeter and it was flying all over the place. Jump the diagnostic wire again but this time give it about 1/4 throttle and turn the key on and see if it throws a code then.

Second of all see if the IAT is plugged in.

I checked my intake air temperature sending unit in the Tb and also in the AFM. While i had the AFM out I tested the function of the slid/flap resitance. I found that is was all wacy. I had this same problem with my 88 flap AFM and had to clean the carbon slide, which is easy on that design, however the s5 AFM is not so easy. Here is what I dd. I will be able to try it soon, and let you know how it works.
Tested
http://www.youtube.com/watch?v=sVOys..._order&list=UL
After taking it apart and testing it.
http://www.youtube.com/watch?v=tFs9W..._order&list=UL
and a fun clip of cutting it and putting it back together.
http://www.youtube.com/watch?v=itjuX..._order&list=UL