Can someone look this over.

[Juststout]

Hi All,

this is a quick idle log, would someone be willing to look it over and give me their thoughts on it. Quick run down on the truck, its a 71 C10 with a 00 5.3 truck motor, with a LJMS Stage III truck cam and FIC 365CC injectors, long tubes pretty much stock and running the MAF. It's a PSI conversion base tune that I have gone into and changed injector data and attempted the EOIT on. i haven't been able to log AFR's yet with my MPVI2, my pro-link cable should be here tomorrow but at idle they were bouncing between 14.7-16.0. I noticed my idle counts were up around 80-90 and then it quit registering IAC counts.

Any help is appreciated, Thank you.

Idle Log 6-9-19.hplTuning Default.Channels.xmlBase_Tune_MAF_CAM_FIC_365CC_INJ_Rev_3_042619.hpt

[5FDP]

What's your fuel pressure?

And is the exhaust complete or it is still open headers?

Are you for sure you have zero vacuum leaks and exhaust leaks pre-o2 sensor?

I ask these because those fuel trims are completely whacked and they are doing everything in their power just to try and bring the fueling back to normal. Adding in 20-30% on the short terms and having the long terms pegged at +25 is saying something is off.

Even a with a decent camshaft and long tubes it should be that bad right away. You even have the injector data put in there so that should be helping some.

[Juststout]

Fuel pressure should be 58PSI, its running a corvette style filter/regulator set-up. exhaust is complete, there is a small leak pre-02 on the passenger side, the collector to x-pipe uses a band style connector and I saw a small black mark on the collector where exhaust has been leaking. I'll have to look for vacuum leaks and try and get the exhaust leak fixed.

[5FDP]

Yeah, check for the leaks and get the exhaust thing squared away.

See if anything gets better just with that.

If it's still sorta the same way, do a global fuel change just as a test to see if it really is needing that much more fuel just to keep it happy. Add 5% to the entire MAF curve and to the entire Primary VE table. If the fuel trims start to come back down, then you are working in the right direction.

[Juststout]

I found a port on the intake I didn't have plugged, it was a steam vent on on the throttle body not sure if that does anything or not but I logged trims with that fixed, and it was the same as before. So I added 5% (multiplied tables by 1.5%) to my Main VE table and to the MAF (airflow Vs. Freq. table, hopefully this was the right spot?) and the LTFT's and STFT's were way better, except for LTFT B1, it started to creep more then B2. I was looking Both 02's are in the collector of the header, all exhaust leaks are post 02 but not very far from it, maybe 1-2" max so I will try and get the exhaust leaks fixed. attached is the log with 5% fuel added.

Added 5% fuel.hpl

[Oleblu]

1.5 would be 50% 1.05 is 5% From your description you just added 50% fuel.

[Juststout]

You are correct, no wonder the trims were happy... I'll adjust this Thanks.

[Juststout]

Ok, I think I resolved the exhaust leaks, got my AFR gauge installed and working & logging. I started playing with the tune a little bit more. Any feedback would be appreciated the truck seems to idle decent, I noticed on a small drive it seems to have a misfire or a stumble somewhere between 2-3k RPMs in drive2 log file. Attached is a idle log, and a couple quick little drives up to the ice cream shop with the wife.

Tuning Default.Channels.xmlBase_Tune_MAF_CAM_FIC_365CC_INJ_Rev_3_SD_Trial.hptidle.hpldrive.hpldrive2.hpl

[5FDP]

Bank 1 still is doing something weird, the trims are okay at idle but once in the throttle it's saying it's way lean still and adding in a bunch of fuel.

If your wideband is in the drivers side, it seems to follow what it is doing as your wideband reading is way rich as it's adding in fuel.

I'm curious if that O2 sensor is causing an issue. Could be worth it to swap the sensors side to side to see if that same condition follows to the passenger side.


Otherwise it seems to be driving fine. You can start open loop tuning the MAF and VE table now if you want. Then come back to closed loop and see if your fuel trim problem is still a concern or swap the sensor side to side now as a test then start MAF/VE tuning.

[Juststout]

Yeah WB is in driver side. Hmm i'll try and swap sensors tomorrow and see what it does.
Thanks

[Juststout]

Tonight I swapped Bank 1 02 sensor with bank 2 02 sensor and took it a drive around the neighborhood, and after taking it for a drive it looks like B1 is still acting up... Hmmm


Thanks.

swapped B102 to B202_2.hpl

[Juststout]

Yeah not sure whats going on, seems to idle ok and the trims look ok, as soon as im in the gas bank 1 just wants to peg 25% again.

swapped B102 to B202_3.hpl

[Juststout]

what do you think about disabling the LTFT's until i can get something figured out why bank 1 is acting up?

[5FDP]

Go for it.

You could see if anything changes after open loop tuning with your wideband as well.

[Juststout]

Somethings not right... look at the tune at the 19:47 mark and now both LTFTs are maxing 25%

Idle Log 6-14-19.hpl

[5FDP]

Well, that sounds like fun.

Do the basics I guess, like checking fuel pressure with a mechanical gauge.

Even try disabling the MAF sensor and running it off speed density in closed loop. That would let you know if the MAF is faulty.

[Juststout]

yeah ton of fun. Earlier today I was playing with it in closed loop, seemed ok at Idle but anywhere else it was super lean so i didn't mess too much with it. after putting it back to open loop it gave me a P0355 DTC, which was the #5 coil so i replaced that. Tomorrow i'll try closed loop again and try adding some fuel

[Juststout]

I swear every time I plug into this thing it's doing something different... This log the LTFT's look fairly even under acceleration they drop fairly consistently under throttle but light throttle and idle they peg at 25% which leads me to believe its a vacuum leak... hmmm


Idle Log2 6-14-19.hpl