LS2 engine with very rare issue

[wnagel]

Hi,

My name is Waldo Nagel, I write from Santiago of Chile, some month ago I install in a pontiac firebird 1974 a LS2 engine , this unit has come from a Silverado 1500 2005.

Well...

1.- Its come with original harness, I rework use a original wiring diagram, I remove all wire from automatic transmission.
2.- I use the original topology for power distribution was used for chevrolet....
3.- The ecu has a all negative wires put in the engine.
4.- We has remove the original intake and put a a new one from corvette with the stock injectors ,(from corvette).
5.- A friend who know use hptuners has removed VATS.
6.- A friend has set the ECU with new parmeters.
7.- Its was store the original firmware to use in any case.
8.- We buy a new pair of oxygen sensor buy from rockauto, AC DELCO Part number : 213 17 02
Well...

The car start fine in a open loop, but when take temp the ECM shut off 4 cilynders between 1000 to 2000 rpm, Its aleatory because put off right head and left head.....

When take 2000 rpm or more activate the head was shut off..... and run in 8 cylinder....the engine run very well...

Its make my crazy.....

I presusme is a ECM faulty or maybe a problem with set the new injectors or maybe a bad new set.

Sorry for my bad english I know is too bad.

Maybe some one can help me.

Thanks in advance.

Waldo.

[DGS]

So the question is are you losing a bank/head of injectors or coils? Cylinders 1,3,5,7 (left bank 1) or 2,4,6,8 (right bank 2)? Or is it cylinders on both banks/sides/heads of the engine. Here are most of the wiring diagrams. Maybe you can review how you wired it up. Each bank of coils and injectors is powered by a fuse. Loss of power to bank/head will take out complete bank/head/side of cylinders. Possibly look there? I am working with limited info. and slight language barrier.

[wnagel]

So the question is are you losing a bank/head of injectors or coils? Cylinders 1,3,5,7 (left bank 1) or 2,4,6,8 (right bank 2)? Or is it cylinders on both banks/sides/heads of the engine. Here are most of the wiring diagrams. Maybe you can review how you wired it up. Each bank of coils and injectors is powered by a fuse. Loss of power to bank/head will take out complete bank/head/side of cylinders. Possibly look there? I am working with limited info. and slight language barrier.

DOGS,

Thanks for your time, , all injectors and coils are powered, the issue is randomnly , some time put very lean left head and very rich the right head, past time...put lean the right head and rich the left head, both O2 sensor was new , (Pre catalyst). In a cold start run well but when take temperature the engine start with this issue, but if you drive over the 2000 RPM, the engine run well without notice.

I use wiring diagram for On Demand 5.

Thanks

Waldo