Help, Misfire/hiccup/ No Idea

[Hitthebottle90]

hey all, here's issue at hand and can't figure out, car is a 1990 302 gt40 iron head get 40 intake, got 24lbs injectors and massair, Car has a gremlin, at times will start up fine no problems, other times you start it and it dances around the idle dropping from 400-1200 rpm, here's my big issue, come into 3rd gear and put my foot into the things ass and it's a rocket, after the top of pull I throw into higher gear and " cruise" then intermittently will either run fine or developed this "misfire / stumble / I have no idea ,sometimes even here like a pop noise " it has like 1/4 of the power it usually does until I put my foot in the things ass again and it will clear up, then you can just be driving normal and no rhyme or reason it will start doing it again until you matte the gas pedal to clear it up, I'm lost, I did. Cap rotar wires plugs (yes there gapped) o2 sensors brand new mass air n injectors someone hopefully will have answer or similar problem that they have fixed,currently I scanned car with the snap on brick scanner and codes were 44,32,33, There is no longer a smog pump or canister, the heads were blocked off and doesn't sound like there are any vacuume leaks, timing is at 12 deg , sounds electrical to me only because when you fully floor it prob goes away. Then again I'm unsure and Any help would be greatly appreciated Thank you

 

[General karthief]

Check out the surging idle checklist in the 5.0 tech/how to section
Also make sure your grounds are clean and tight.
I suspect a vacuum leak but don't rush to any conclusions.
You ran koeo and koer tests?

 

[Hitthebottle90]

The surging idle only happens when the "misfire/stumble" is active then when you floor it clears up again, could it be tps or iac related?

 

[General karthief]

Yes or no. Go through the list, you'll likely find the problem without chasing your tail and wasting money try'n to guess what is wrong. jrichker and others have put together that and other lists to help us diagnose problems with these cars and have years of experience with diagnostic procedures on efi cars and the eec iv systems
Most of the problems I have found are poor grounds or grounds that were unintentionally left off.