Turbo LS huge swings in Afr

[Zanderf16]

I'm pretty new to tuning but learn pretty fast I've been seeing huge swings in AFR, the colder it is the more rich it is. Obviously this makes it very difficult to dial in the ve table. I've been running around e50 to e70 but have had to run different stoich ratio to change with different temperatures. The truck has been doing this long before I started running ethanol. It makes it impossible to dial in the ve because it changes so much from day to day. IAT sensor is in the manifold. Stock engine, 7875 ,65 lb injectors walbro 450.

[edcmat-l1]

Yep look at that.

[Zanderf16]

Yep look at that.

2-27 tow haul tune.hpl2-27 trans tune rip.hpl2-27 11.5 trans tune tow haul.hptgood one.Channels.xmlinnovate wb02.MathParameter 2.MathParameter.xml

[Zanderf16]

Look at IAT?

[edcmat-l1]

What are we supposed to be looking at and why does it look like half the stuff in that PCM is not working?

[Zanderf16]

My calibrations seem to be correct it reads what the temp is outside, it does heat soak a little when idling but not very much. Is there a table that tells the computer how much fuel it needs from the IAT? I have change the cylinder charge temp bias from stock to 2.0 and back to stock with no change.

[SiriusC1024]

Easiest thing to do is put the IAT in the intake manifold. After that disable Complex Temperature Model, as recommended by HPT table/setting description.

[Zanderf16]

I'm not really sure what to look at That's why I'm asking you guys. This is my first post on here, I don't know what more you need. What doesn't work in the PCM? Seems to work fine other than the over fueling issue. It is a year 2000 p01 PCM.

[Zanderf16]

IAT is in the IM I have not heard anything about the complex temp model. I will disable it and give it a try thanks!

[5FDP]

Who's injectors did you install?

What kind of fuel system is it. Return or returnless? How are you controlling fuel pressure with that 450lph pump?

What MAP sensor is that?

[Zanderf16]

Easiest thing to do is put the IAT in the intake manifold. After that disable Complex Temperature Model, as recommended by HPT table/setting description.

Is the complex temp model the same as cylinder charge temp bias?

[Zanderf16]

Who's injectors did you install?

What kind of fuel system is it. Return or returnless? How are you controlling fuel pressure with that 450lph pump?

What MAP sensor is that?

I'm not 100% sure on the injectors. I'm going off of previous owners data. So that could be off. Return style stock regulator. Map sensor is 3 bar.

[5FDP]

You really need to make sure the injector data is correct, not even worth tuning it if that data is wrong.

I also doubt that the stock regulator on the fuel rail is able to maintain the proper pressure with a 450lph pump, those things flow a ton a fuel. I'd be installing an aftermarket regulator to maintain a constant 58psi of fuel pressure.

And the 3 bar MAP was a give away but what 3 bar MAP? I've never seen linear and offset data like that before.

[Zanderf16]

You really need to make sure the injector data is correct, not even worth tuning it if that data is wrong.

I also doubt that the stock regulator on the fuel rail is able to maintain the proper pressure with a 450lph pump, those things flow a ton a fuel. I'd be installing an aftermarket regulator to maintain a constant 58psi of fuel pressure.

And the 3 bar MAP was a give away but what 3 bar MAP? I've never seen linear and offset data like that before.

Ok I'll take a look at the injectors. The PO gave me a boost ref. regulator. I'll also try and find out what Map sensor is in there, thanks for the info