help! bad stumble and low boost

[married284gn]

Here is the problem: car idles fine but stumbles real bad under boost........can barely get over 5 lbs........plenty of black smoke as well.
Bought this car a year ago and it was not running so I have no idea of history.
I have checked fuel pressure.........it seems okay. Replaced coil pack, MAF, O2, plugs & wires, ecm, new stock turbo, rebuilt heads, checked TPS. Unplugged cam sensor and no change. I am running out of ideas(and money). No ecm codes registered. I don't have a scan tool........transmisson in daughters car took the money saved for that!

Any ideas will be appreciated!

 

[Roger]

Only a guess here, but your description points to a injector to chip missmatch.
You must hav a chip for the size injectors in the car.
HTH

 

[married284gn]

Thanks for the suggestion..........how do I tell what size injectors I have? I have the stock chip and a hypertech performance chip and the problem is the same with either in.