Sputtering and underpowered

[jameshammett]

Is an 87 7mgte all stock with open down pipe. And aIr filter.
When diving it sputters when building boost then when at boost the car feels really nderpowered and it's running rich. But my boost gauge is reading steady but it feels like it's not picking up speed and it just sputters when you trying to boost. But it always starts up and a idle it runs fine any ideas what it could be would be great thanks... Sorry for th mistyping my iPhone seems to change what I'm saying a lot lol

 

[whitemike]

Specs? Mods? When did this start? What did you mess with around the time this started?

 

[jameshammett]

I put new champion copper plugs put an open air filter. And shimmed the waste gate to 7psi. And cut the down pipe after the cat. And an evo bov. That all the mods it started fours days ago and since then I checkedthe plugs did the fuel volt mod cut the muffler off checked timing fresh oil change.that all I've gotten to since the problem started

 

[whitemike]

So the car was running fine AFTER the mods, and then just randomly started doing this? Or did it start when you change plugs, or air filter, or waste gate, etc.

 

[jameshammett]

it ran good after the mods, it just started acting up a few days after the mods

 

[whitemike]

Check resistance on your CPS coils

 

[jameshammett]

do you know a good thread on how to do it I clicked the search button but nothing happened?

 

[whitemike]

http://www.cygnusx1.net/Supra

 

[radiod]

If it's sputtering and running really rich it will likely be a spark issue. Check to see that you haven't fouled a plug, just to be sure. Check your plug wires, make sure they're tight and not cracked and actually carrying the spark to the plug properly. Check your resistances. Those are all good places to start.

 

[jameshammett]

i put a different coil pack, bov, and re doing the intercooler parts. check plugs. after that i replaced the afm it fixed the sputtering problem but round 3-4000 it hits fuel cut or runs poorly. i shimmed the waste gate but it only went to 7psi.