Startup tune TT 5.3 80lb SD's 3bar - Check my log/tune

[kunta0908]

1990 300zx swap

Having some issues getting this thing idling so i can progress with the build.

After tossing the corvette fuel filter/regulator that was for some reason, giving me 70psi fuel pressure. I went ahead and setup an AFPR with vac reference.

Running 58psi fuel pressure with reference off.

Took a stock tune, 3 bar'd it. Set MIL's for MAF failure. Turned LTFT's and STFT's off, yadda yadda...

Set up injector data for a boost referenced system using Deka data provided in an older thread by JakeFusion.

Added a bit to the base idle airflow.

Map sensor is a 3 bar LS3 style sensor bought from On3 (purchased the 2bar and they were out of stock and sent me a 3bar). Used a pigtail to convert my wiring harness pigtail to use it.


Car starts and will idle, sounding really odd, bno misfires being logged though. Wideband says im lean.

MAP sensor says im 75-90kpa while idling. Which.... Points to a vacuum leak?? I just don't know where it could be. I sprayed down my manifold with starter fluid, to no avail.

Injector pulsewidth wont go below 3.5ms

Also throwing a p0336 code. CKP sensor performance. Replaced sensor, no change. Checked wiring, seems good. Fuel pump clicks on while testing it out of block and waving a wrench in front of the sensor.

Gonna replace the plugs, the 70psi regulator was just dumping fuel and I know they have to be pretty black and fouled. Aside from that though, why in the hell (aside from a gaping hole in the intake I must have missed when searching for vacuum leaks), am i getting such a high idle map reading. And the p0336 code confounds me as well. Reluctor wheel hasn't been touched. SBE 5.3.

I do have a boroscope that I plan on checking out the wheel with as I spin the crank by hand. Just to ensure no wheel damage. Also have a spare PCM to try out to rule out any oddball PCM problem.

Anyone care to check out the tune and see if they can spot anything glaringly obvious I have forgotten?

Log and tune attached.

19-05-25 09-53-47.hpl
300z 3 bar 80lb AFPR Fueling.hpt

[kevin87turbot]

According to your wideband data, it's very lean...1.2 AF ratio. Does it seem that lean? Here's a quick test...go to VCM Controls and add fuel. See what happens to your MAP. If the MAP kPa drops, then it's simply running lean. Are all 8 plugs the same color?

[5FDP]

Don't forget to set the MAF fail hz to 0hz, it's still at 13,500hz.

Go back to a stock OPEN LOOP EQ ratio table, then have it tail down to 1.00 after 120-130 degrees. It won't like trying to start cold when it's commanding stoich that quickly. It should run better if it was running around .85 to .90 lambda then working it's way leaner at operating temp.

If you remove parts or other things too, disable those codes just because. Like all emission related parts, rear o2 sensor etc etc.