Rich Idle with fan running lean with out

[kostelacd69]

As the title says engine runs rich with cooling fans on, when they switch off it goes super lean. Tried SD with MAF disable and no change. Turned on short terms and it corrects for each scenario. You can add fuel to the VE and MAF table in those areas and there is no change in AFR. Im lost, have never seen this. This is a 5.3 216/220 /550/.550 on 112. 50lb Flex fuel injectors at 40-45 PSI rail pressure. Fast 92mm TB LS2 Intake shorty headers in a XJ cherokee.
I have posted the tune and log. At the end of the log the cooling fans turn on then goes rich. Ideas?

[ProperTuningOG]

What does voltage due? Also, why is the rail pressure so low? If you used GM injector data everything is based on higher pressure.................

On second look. I compared your injector data to the injectors you said you used. I'd double check your injector setup.

[kostelacd69]

Battery voltage stays at 13.5. Fuel pressure also stays steady. Pressure is low because I'm using the stock jeep internal regulator. Injectors data came from the truck that the injectors did. They 50lb @ 58 psi. Just lowered the flow rates by that percentage. Also I have tried running a 2002 camaro OS and a truck OS with no change. Changed all the injector back to stock 02 camaro and Silverado. No change. Played injector flow rates up and down. No change. And when I say no change it still did it. Maybe differ aft numbers but symptoms were still the same

[joecar]

Where is your air cleaner inlet located (does MAF see fan air blowing on it)...?

Post pic of engine bay.

~ posted by phone ~

[kostelacd69]

Here is a picture of the bay. The Rad and Fan are offset to the passenger side and the filter is in the driver side corner. I also tried in speed density with the MAF disabled (c2901 set the fail in the tune to 1HZ) and still does it.
Thanks

[kostelacd69]

Stupid ass Iphone. Cant get the photo up right sorry

[kostelacd69]

Now fuel trims wont turn back on.

[ProperTuningOG]

Injector data is much more than flow rates. The file up has 1 part changed and the rest not.

[kostelacd69]

Injector data is much more than flow rates. The file up has 1 part changed and the rest not.

Very true, I originally had the other 4 tables changed for the 50# injectors but in a attempt to get back to a stock tune as possible i change almost everything i could back to stock to see if it was something i did. Thats why only flow rate is changed in the above tune. Once I figure out the problem now with short terms not working i can get back to the rest of the tune.

I am going to cut apart the intake tube and add a air straightener to see if that help with the rich/lean condition. Like JoeCar said maybe some fan air is working its way over there.

[kostelacd69]

Update, after thinking about failing the MAF by setting the fail number to 1HZ I tried unplugging the MAF all together. After that the engine stopped doing its lean and rich idle. So that says the MAF is seeing more turbulent air from the fans (it wasn't very steady to begin. 5.3 + cam + 4 inch intake tube= slow crappy air), so I cut the intake tube apart, added a air straightener and its fixed! Now on to the short terms. This computer was reading long and short terms, it was also reading Park and Neutral from the switch. It now doesn't do any of those things now. In fact the o2 voltages are way off all the time on both sides regardless of AFR and rpm. Did a full reflash of the original tune i started with that i knew it all worked on and still nothing. Guessing the PCM is a POS. Going through the process of getting another one.

[joecar]

Here is a picture of the bay. The Rad and Fan are offset to the passenger side and the filter is in the driver side corner. I also tried in speed density with the MAF disabled (c2901 set the fail in the tune to 1HZ) and still does it.
ThanksNice install, looks better than factory :cheers:



When you run SD do you get an immediate MSF DTC (if not then it's still using the MAF)...?

[joecar]

Here is a picture of the bay. The Rad and Fan are offset to the passenger side and the filter is in the driver side corner. I also tried in speed density with the MAF disabled (c2901 set the fail in the tune to 1HZ) and still does it.
Thanks


Stupid ass Iphone. Cant get the photo up right sorryThose pics show 2 different engines...

[joecar]

+1 what Team208 said above.

Also, IFR table depends on whether FPR is referenced or not, and on rail pressure.

[kostelacd69]

Same engine in the same jeep. I will attach one better. As for fuel pressure it is 45 non ref.
Here is the final tune.

[kostelacd69]

Nice install, looks better than factory :cheers:



When you run SD do you get an immediate MSF DTC (if not then it's still using the MAF)...?

I did not. So would explain why i thought it wasnt MAF or MAP related.

[kostelacd69]

Also you'll see in the photo that I'm running both the gm and jeep computers. Thats so I could retain cruise control, air bag function and full gauge cluster

[joecar]

I did not. So would explain why i thought it wasnt MAF or MAP related.Without a MAF DTC the ECM will attempt to use MAF, even if it has to calculate it.

[joecar]

Same engine in the same jeep. I will attach one better. As for fuel pressure it is 45 non ref.
Here is the final tune.Ah, I see now, I was getting confused by the images being upside down :) I have to work on that skill :)

[joecar]

Update, after thinking about failing the MAF by setting the fail number to 1HZ I tried unplugging the MAF all together. After that the engine stopped doing its lean and rich idle. So that says the MAF is seeing more turbulent air from the fans (it wasn't very steady to begin. 5.3 + cam + 4 inch intake tube= slow crappy air), so I cut the intake tube apart, added a air straightener and its fixed! Ok, this is good to know.


Now on to the short terms. This computer was reading long and short terms, it was also reading Park and Neutral from the switch. It now doesn't do any of those things now. In fact the o2 voltages are way off all the time on both sides regardless of AFR and rpm. Did a full reflash of the original tune i started with that i knew it all worked on and still nothing. Guessing the PCM is a POS. Going through the process of getting another one.Check all the engine grounds, and check all the fuses.

[kostelacd69]

Figured it out. 02 Camaro tune only requires one ground to see park and neutral, where as the truck OS requires two (pin 32 and pin 34). That is why I would see park/neutral in one OS and not the other. As for the for the fuel trims, one o2 was hanging out at .435 to .465 volts. That tells the PCM that the o2 is bad and wont start fuel trims. All fixed and working.
Thanks

[joecar]

Figured it out. 02 Camaro tune only requires one ground to see park and neutral, where as the truck OS requires two (pin 32 and pin 34). That is why I would see park/neutral in one OS and not the other. As for the for the fuel trims, one o2 was hanging out at .435 to .465 volts. That tells the PCM that the o2 is bad and wont start fuel trims. All fixed and working.
ThanksThanks for posting back.

Did the GM truck wiring diagram show 2 grounds for the P/N switch...?

How was this fixed...?

[kostelacd69]

The truck diagram shows the two pins doing different things but after looking at the truck and camaro diagrams figured out that both pins could take a ground. Decided to share the same ground from the pnp switch and then it worked.

[kostelacd69]

As far as fuel trims I replaced the week old o2's with new ones. Fuel trims turned right on.