Need help finding out what's wrong with my 99 Tahoe

[buckwheat]

Here is everything that has been done so far. New long block, distributor cap, rotor and gear, delphi spider injector set, fuel pump, fuel filter, spark plugs, spark plug wires.

Basically it runs terrible has no power at all and stumbles constantly. My dad works at a GM dealership and we've took it there twice to have them check it out. They set the timing and checked fuel pressure and it didn't have enough which is why we changed out the pump. Its like a never ending problem. Any thoughts or ideas about what it could be would be greatly appreciated.

 

[strad]

I would certainly want to know if the engine had compression in spec and a good leak-down test. It may be new but that doesn't mean that somebody didn't eff up somewhere.

I'd also want to know if correct fuel pressure, fuel delivery and correct response from tps and mass air flow sensor.

Beyond that I don't know.

 

[retorq]

If it's a 99 hook a scanner up to it and look at the real time data that should tell you, your dad, the techs at the GM dealership and all my dead relatives exactly what is wrong.

 

[SunlitComet]

was a new regulator already installed on the delphi spider or old one reused?

 

[buckwheat]

The new one came with a new regulator. They hooked it up it was throwing no codes everything showed it was perfect. I have been curious about the tps and mass air flow sensor. It idles perfect, revs perfect when in park or neutral but as soon as it gets a load on it, it stumbles. Its been an on going money pit and its extremely frustrating.

 

[SunlitComet]

have you got reading on your map sensor?

 

[knoslf]

The new one came with a new regulator. They hooked it up it was throwing no codes everything showed it was perfect. I have been curious about the tps and mass air flow sensor. It idles perfect, revs perfect when in park or neutral but as soon as it gets a load on it, it stumbles. Its been an on going money pit and its extremely frustrating.

Ever get it figured out? My 99 Yukon doing the same thing

 

[retorq]

Ever get it figured out? My 99 Yukon doing the same thing

See post #3.