97 v6 vortec

[Willy97chevy]

As I understand he plugged in ecm for v8 but it just operates 6 cylinders instead of 8. That's how I understand it.

Yes sir I did the v6 to V8 swap but plugged the v8 in and it still runs on 6 cylinders evidently. I can't quite figure it out. Am I missing something?

 

[Willy97chevy]

What problem are you having? Can you go back to the beginning and explain your problem please? Give us some history or background.

What is the truck? Year, engine, etc.

What were you trying to do? You swapped an engine?

What problem are you having?

I'm having problem with v8 not giving me all 8 cylinders while running.

 

[HeavyAsAChevy]

Did you run the two extra injector wires?

 

[stutaeng]

Yes sir I did the v6 to V8 swap but plugged the v8 in and it still runs on 6 cylinders evidently. I can't quite figure it out. Am I missing something?

I see. You should do some basic diagnosis. Check for fuel pressure, check for spark, check for injector pulsing...things like that.

Since you swapped the engine, do you know for a fact the V8 engine didn't have these same problems? What was the history on it?

If you swapped the ECU, I highly suspect it's not because the engine is somehow running on the V6 firing order or something like that.

 

[Willy97chevy]

Did you run the two extra injector wires?

How do you run the two extra injector wires is what I'm really needing to know. 97 Chevy ext cab vortec v6 to v8 vortec. I'm really having a headache over this.

 

[Willy97chevy]

I also can't understand that OP is asking. I'm thinking he's doing a V6 to V8 swap. How the ECU controls the additional 2 injectors?

Simple question how does a man run the 2 extra injector wires to run all 8 cylinders.? I'm so stumped

 

[Willy97chevy]

As I understand he plugged in ecm for v8 but it just operates 6 cylinders instead of 8. That's how I understand it.

Yes sir is there something I'm missing to make this not happen? Is there something I still need to do or unplug or fix?

 

[stutaeng]

Simple question how does a man run the 2 extra injector wires to run all 8 cylinders.? I'm so stumped

The simples thing for a plug and play approach would be to use the engine harness from the V8.

You can make your V6 harness work, but you need the 2 additional injector wiring, and re-pin the wires on the ECU main connector. I had seen a thread on the S10 forum on how to do this. Let me see if I can find it for you.

 

[Willy97chevy]

Okay

The simples thing for a plug and play approach would be to use the engine harness from the V8.

You can make your V6 harness work, but you need the 2 additional injector wiring, and re-pin the wires on the ECU main connector. I had seen a thread on the S10 forum on how to do this. Let me see if I can find it for you.

I have a v8 harness in it now. I don't understand why it seems like a miss or something but it runs rough at idle. With foot on break and take off.

 

[HeavyAsAChevy]

Lt1swap.com has a pin diagram for V6 to V8 swap harness.