Help my car stop Stuttering...PLEASE HELP

Ok here is the situation....
AFTER the car gets to normal temp at about 2000 rpm my car jus starts hessitiating then it will pick up and do it again... i havent noticed it doing it that much at higher rpms but i have felt it do it...it almost feels like its not getting gas thats the only way to describe it...

Here is what i have done to try to fix the problem so far...with no luck
255 pump
fuel filter
fuel pressure reg. Adjustable
MSD 6al
blaster 2 coil
auto lite 25 plugs .060 gap
new ford wires 9mm
Rotor and Cap
Throttle position sensor

So where do i go from here....someone told me (im not sure what it is called but it is facing the front of the car on the throttle body with a plug going to it) to take it off and clean it out with carb cleaner. Also to check my timing...but i dont know why all the sudden my timing would have anything to do with it when it only does it when the car is warmed up..

other stuff on the car
89 with 170,000 miles
24# inj with sensor
trick flow street intake manifold
70mm TB
full exhaust

Please help me...im running out of ideas and money
 
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A high speed miss when the engine is warm & the plugs, cap & rotor are good, is usually a bad TFI module.

The TPS should be less than 1 volt. You'll need a good DVM to set it. There is some question about the advange, if any, about setting the TPS voltage at .98-.99. Anything from .70 to .98 should be good.

Here’s a TPS tip I got from NoGo50…

When you installed the sensor make sure you place it on the peg right and then tighten it down properly. Loosen the back screw a tiny bit so the sensor can pivot and loosen the front screw enough so you can move it just a little in very small increments. I wouldn’t try to adjust it using marks. Set it at .80v-.98v. Just don’t go over .99, or you upset the fuel calibration and idle quality will suffer.

(copied from MustangMax, Glendale AZ)

1. Always adjust the TPS and Idle with the engine at operating temp. Dive it around for a bit if you can and get it nice and warm.

2. When you probe the leads of the TPS, do not use an engine ground, put the ground probe into the lead of the TPS. You should be connecting both meter probes to the TPS and not one to the TPS and the other to ground.

3. Always reset the computer whenever you adjust the TPS or clean/change any sensors. I just pull the battery lead for 10 minutes.

4. Check the procedure for your year, on my 90 I have to turn the idle screw until it just touches the tab, then insert a .010 feeler gauge and give it about one more turn. Then you adjust the TPS voltage to .80-.98v, reset the computer. Start it up, if the idle is to low then turn the screw in until it is just right, then readjust the TPS voltage to .80-98v and reset the computer and start it up. The key is to adjust the TPS voltage and reset the computer whenever the idle screw is changed. Code 63 - Throttle Position Sensor (TPS) signal too low TPS. Vref missing (5 volt reference voltage supplied by the computer), bad connections or damaged wiring, TPS sensor failed, TPS sensor way out of adjustment. Use a DVM to check for 5 volts on the Orange wire. If it is missing, look for +5 volts at the Orange wire on the EGR or MAP sensor located on the firewall near the center of the car.

Here’s a TPS tip I got from NoGo50…

When you installed the sensor make sure you place it on the peg right and then tighten it down properly. Loosen the back screw a tiny bit so the sensor can pivot and loosen the front screw enough so you can move it just a little in very small increments. I wouldn’t try to adjust it using marks. Set it at .80v-.98v. Just don’t go over .99, or you upset the fuel calibration and idle quality will suffer.

(copied from MustangMax, Glendale AZ)

1. Always adjust the TPS and Idle with the engine at operating temp. Dive it around for a bit if you can and get it nice and warm.

2. When you probe the leads of the TPS, do not use an engine ground, put the ground probe into the lead of the TPS. You should be connecting both meter probes to the TPS and not one to the TPS and the other to ground.

3. Always reset the computer whenever you adjust the TPS or clean/change any sensors. I just pull the battery lead for 10 minutes.

4. Check the procedure for your year, on my 90 I have to turn the idle screw until it just touches the tab, then insert a .010 feeler gauge and give it about one more turn. Then you adjust the TPS voltage to .80-.98v, reset the computer. Start it up, if the idle is to low then turn the screw in until it is just right, then readjust the TPS voltage to .80-98v and reset the computer and start it up. The key is to adjust the TPS voltage and reset the computer whenever the idle screw is changed.
 
ok...timing is good...tps is good...So i went to my buddys and decided to use his mass air sensor... and it stiull did the same thing...so then we decided to take off my distributer cap, then he shook the inside and it was a lot looser than his.... so i guess im gonna try to get a new distributer
 
Check sparkplug gaps.

My car was almost undrivable after adding heads,cam,intake and TB.
i tried everything to get it right,took it to the proshop had a diablo chip put in it and had it on the dyno etc and it still ran like ****.

Called a friend and he said change the gap on the plugs to 40 cause it was getting so much more air and that fixxed it.
 
Well it was the distribitor....So thats jus a heads up to people if they are having some of the symptoms mine was... take off your cap and try to jiggle the rotor side to side and see if it all moves... when i pulled my old one out you could really tell it had alot of side to side and even up and down play... compared to the new one which has none side to side...and barley moves up and down