Stock ECU air fuel turbo observations at 5 pounds (1 Viewer)

[landtank]

@scottryana and @landtank

So AC running today mid 80's driving 70MPH under 10-15 pounds of vac I see the A/F meter going all over the place. Rich lean rich lean.

The computer tries to compensate but it is not fast enough.

@landtank Timing is massive. Before I replaced 1 knock sensor and adjusted the timing I pinged like crazy.
I would have to check the timing again, comes to life hard at 2800- 3000 but you know she is there at 2k.

You might want to change your fuel pump relay. I've seen these things not control the pump consistently on stock trucks.

On my SC I've been using NGK BKR7E plugs which are 2 heat ranges cooler and a copper plug. They have been running flawless even in the dead of winter. You can get them at advance auto for under 2.00ea, I'd give them a try.

 

[scottryana]

You leave the stock computer in place and it controls the transmission.

Sub'd, I want to see how this goes, because you know boost is addictive. If some is good, more is better. Also would be good to know how smart I have to be to add a stand alone. Does that Haltec control Trans too?< looked it up it doesn't. How will you deal with trans?

 

[asuddendeath]

You might want to change your fuel pump relay. I've seen these things not control the pump consistently on stock trucks.

On my SC I've been using NGK BKR7E plugs which are 2 heat ranges cooler and a copper plug. They have been running flawless even in the dead of winter. You can get them at advance auto for under 2.00ea, I'd give them a try.

Running stock plugs now, I have a set that is 1 range cooler.


A/F stuff I was talking about

 

[RoaringFork]

That’s normal of a system working in closed loop... the O2 sensor pattern is a sine wave where approx. 14.7:1 is the middle. When cruising at (constant-ish) load, the ECM is making minuscule fuel trim adjustments to hit ~14.7:1, the o2 sensors are reporting the adjustments on your A\F gauge...

 

[scottryana]

You're in vacuum.

Running stock plugs now, I have a set that is 1 range cooler.


A/F stuff I was talking about