Just Starting...

[EasyLife]

So it has taken me a 20+ years of listening to friends about their projects, and I just jumped into the deep end. I recently picked up a 84 C10 that has already been thru a LS swap (99 Sierra 5.3) along with a 4L80 (2002-2003 Unknown donor). It has long shot headers, mild cam, and is running a wide band. During the test drive I noticed it appears to struggle mid acceleration before pulling hard again. According to the wide band it is running lean (going from 14.7 > 18+ on acceleration).

So, I bought a MPVI2 and did a baseline data collection and a few basic pulls with the scanner. I have been going thru Goat Rope and other online videos and courses, found a few files to compare, and I am trying to put in the time to learn.

With all that said, everybody is saying to ask for help....well that is what I am doing. Can I get some input on what people see may be wrong with the posted attachments?

[5FDP]

Yes, fueling looks to be very lean all over the place. Make sure fuel pressure is within spec, so you need to stay around 58psi.

Verify the fuel injector part numbers. If that engine really came from a 1999 they are really small injectors at 21-22lb/hr. This tune file says they are 25lb/hr injectors. And depending on the camshaft installed and the rpm you want to turn, even those injectors will be too small at higher rpm.

Change the cylinder volume back to the 5.3 engine size and not the 6.0 engine size like this tune has it.

Disable abuse mode in the torque mngt tab. Set it to 7,000rpm and 0mph.

Whoever did some of the tune before did a few things kinda wrong. They left the EGR enable (unless you are using that for a wideband input). The cat over temp protection is still enabled. They disabled all your upstream o2 sensor codes so you'd never know if you have a problem with them. Like with this lean problem, the codes are turned off so that why nothing comes up if you scanned for codes.

Figure those few things out and report back.

[EasyLife]

Thank you for your insight. Here is what I found...I am running 25320287 injectors, which are stock 5.3. Is it far fetched to think that the previous owner dropped a 6.0L file because of the 4L80, which is why so many of the values are way out of scope?

What would be the best method to start fresh instead of picking thru the file I have? Should I get a stock 5.3 and segment swap (just watched video on that right after posting) a stock 4l80 tranny config from a stock 6.0L, and upload that on my ECM?

Finally, I have a question on the OS of the ECM. My ECM OS is 9381344. My buddy has a 99 Sierra (OS 9379910) and I have found many 5.3 files in the repository. Can I load a file from another OS ####### onto my ECM?

thanks,

[doorev800]

If this was my setup, first i would do all the things 5FDP said first. Then if you are wanting a stock 5.3 tune, i would get the tune you want then do a compare of both and then go thru every single parameter and just change your current tune parameters to match the 5.3 tune. You know this os tune you have is good so i would just work with what you have.

Then tune the ve and/or maf in open loop to get fueling right. That should bring it right in line.

[5FDP]

I think per google those are the smaller injectors, so either way you'll want to get larger ones for this engine just to know you have enough fuel.

A common upgrade are 8.1 injectors that are 31lb/hr or Silverado/Suburban Flex fuel injectors from that era and those are 33 lb/hr. Those will have plenty of fuel flow.

I would just work with what you have. Flashing in a different OS will just cost you money and time because you'd have to license a different OS. Use the compare and copy feature if you need to copy over stock 5.3 tune data.

[EasyLife]

Much appreciation for your wisdom. I made the changes (first three) as recommended and a few extra pertaining to the Fuel, and it was great. From the first start I could hear and tell a difference, to the the first drive down the road and it accelerated smoother and with noticeable acceleration. It is still running a wee bit lean, and I've attached my data and scan log files for review. I put notes in the data file of the exact changes.

Can you better explain the "EGR" paragraph a bit....thanks.

[Matt Vardaman]

One thing I noticed from the log. Your bank 2 O2 sensor is lazy. Double check the wiring/plug, but most of the time with that data it's a bad/old 02 sensor.

[Matt Vardaman]

What he means by the EGR is that the original owner might have run the Wideband O2 to the egr sensor wire so that you can log the wideband in hptuners with a user math parameter. Normally with a performance engine or swap motor, the egr valve is deleted, but you need to leave it on in the tune if you are using the wires for the wideband. You'll have to check under the hood close to the #2 injector to see if it's wired that way.