Two issues. Idle rises when it should lower and air fuel doesn't follow commanded.

[jon1440]

I did a log starting from cold to warm and my rpm slowly rose to around 1000 rpm, and then somewhat settled down but not to what I was commanding. I have my base idle set to 825 once temps reach 111. At around 111 I'm idling around 950 to 1000. It had been doing fine in the past but started doing this recently. I don't think it could be a vacuum leak because it slowly rises with temps.


For my air fuel problem. I recently enabled my STFT openloop. I'm commanding 1.0 EQ across the board for simplicity. My STFT is about -10. My wideband bounces between two cells. 14.0 and 14.28. I might be looking at this wrong, but my narrowbands say I'm 10% off and my wideband says I'm -2 to -4% off. Not sure what is correct. Also in my tune I have 14.68 for stoich. In my scanner for some reason not sure if it was a default setting or the way I set it up but my Air Fuel Commanded (Lo Res) is at 14.600. Could this be my problem? I've tried to change this but unable to figure out how.

Scan. 2519.hpl

Tune. hhhhh.hpl

[5FDP]

You can remove the lo-res channel, repoll for supported parameters and add in the regular commanded AFR channel. Then it would show exactly what you stoich table is.

Your narrow bands do respond very quickly and if they are closer to the exhaust than the wideband is that could be a slight reason for the difference. Try just removing 2% and see if the trims back down to 5-7%.

Your tune didn't post. But you could try lowering the timing at idle to help it, it seems kinda high just looking at the log.

[jon1440]

hhhhh.hplhhhhh.hpl

I appreciate it. I've tried a lower timing but my vacuum decreases from 12-13 to 10 to 11 iches. I believe its set at 27 now. I lower the timing a little and see if theres any negative side affects. Just searching for the best vacuum I can get.


For the o2's the drivers side o2 is in the stock location, but the passenger side has been moved to the down pipe, and then about 6" on down is the wide band. My down pipe is about 2.5' long. Exits the fender. The wide band I would guess is no more than 1' from atmosphere. I have in the past for noise reasons while running the truck in the drive, put a muffler in the pipe to keep things quiet and noticed my wide band readings not bounce so much. At this point I kinda do want to run the exhaust out the back and install some sort of muffler, so I could listen to the engine better while tuning. I think I'm getting some fresh air pulled back in due to cam profile. I could be wrong though.


Another quick question, currently because of how the hot side is plumbed. My passenger side o2 is reading a mix of B1 and B2.


My options to fix are:


1 Replumb exhaust. Big pain in the ass.

2. Move both o2's to down pipe. o2's will never read their banks independently.

3. Move B2 o2 to stock location, and leave B1 o2 in stock location. B2 o2 will now read B1 because exhaust flow has been reversed on passenger side due to set up.

Option 2 would (I think) give an average of all 8 cylinders. If o2's are working properly, they should read the same thing. For fueling adjustments it would be happening to all 8 injectors instead of just 4 injectors. If there was an injector problem on B1, B2 would now be involved in fueling adjustments.


Option 3 would not allow me to ever know whats happening on B2. If B2 was to go lean, my wide band would be the only thing to notify me. Plus other tuning issues.

So right now B2 o2 gets an average of all eight while B1 o2 gets an average of the 4 on B1.

Maybe why I'm seeing different trims. I did have the injectors flowed and inspected and know there good.

I would like to try option 2 and see what happens. I know this isn't the absolute correct way, but would it work for the time being?

[jon1440]

On my scanner in the channels, Air-Fuel Ratio Commanded is listed or displayed but I'm unable to add it. To the left it has a split rectangle that is diagonal. All my other channels that I can use have the left/right arrows with the exception of my Wideband. The only thing its allowing me to add is the Lo Res, or EQ with the option of changing the units. I believe at one time I had Air-Fuel Ration Commanded plus Air-Fuel Ratio Commanded (Lo Res). Not sure what happened but I'm only left with picking the Lo Res.