z32 rich and non matching dual wb during warmup, random miss when warm

[xlr8]

i figured out that i can only select a limited amount of channels so i de-selected some in order to include both 02's and both sides injector time. did a warmup log today but the readings never normalized at operating temp or even with the a/c on. this car is all over the place. i tweaked the tune a bit, got both narrowbands reading and stoic, but it wont stay there. if i turn on a/c, tap the throttle, or even when i clear learned, the bank match and a/f are off again and dont recover. its literally like anything i do after i get it set, it ignores the tune i just did and goes unpredictable. i think i will order all new aac assembly and see if it helps with the idle searching. the rest is still a mystery.

[Matt]

Re: consult parameters
There is a limit to parameters so disable ones like AAC, battery etc

What about if you take it for a cruise when warm (80degC/140F), at cruise (2000-3000rpm. light load around 1/4 in the map) how are the mixtures there? What does the LHS and RHS injector time and O2/trims look like?

You still need to adjust the fuel map. The top half of it should be about half factory values (since double factory injector size) as you will notice it going rich on boost

[xlr8]

yes the map needs adjusted urgently. but i havent even gotten idle or low load driving consistant, due to the erratic behavior of this engine. it actually cruises nicely but yes also rich at top of map. but since i cant get a consistant tune or bank match yet so i dont trust the load multiplier enough to drive it. i have barely driven for fear of going lean. for example i test drove last year only a couple times, and this year twice after new turbos. hardly at all lol. it does good (other than, as you mentioned the rich boost and also rich 5th gear cruising) but i still fear lean as one bank is almost always leaner off throttle and sometimes even open throttle. i messed with it some more today warm tuning, i got it to where it seems its always the same banks are rich and lean. i will try again tomorrow or this weekend to see if the condition is the same. if so i will log a warmup and swap injectors to opposite banks, log again and see if rich/lean changes sides. from there hopefully i can see logs enough to rule out the ecu, and start digging into the wiring.
also i installed a brand new air controller it helped nothing.
i havent logged cruising with both injector bank times monitored i just figured out how to turn them on. but thats something i can do in the future when i get this crazy problem fixed.
i will keep you posted with any progress.

[Matt]

I know its a pain with the Z32 VG30 engine, but can you go back to the factory 370CC injectors (and factory map). I feel something else isn't right but I want to eliminate the board/ECU out of the equation since it definitely is not right but I can't put my finger on it

[xlr8]

sure thing its no problem, its not too bad pulling the plenum and rails.
i have a set of OEM type2 370cc (purple tops), a couple upper intake gaskets and a type 2 jumper harness on the way. should have everything here in a week.
i will ask for some advice on the software though, i re-traced my steps and i think what i did wrong previously when i had to send ecu to you for a reflash, was select the 500 hp maf, and maybe the wrong software. possibly because when i downloaded the new version of nistune i followed the pop up "quick start guide" and i thought it meant "up to 500hp" for the maf. anyway i want to make sure i put in the correct software for this jdm ecu. (1990 2+2 TT auto to 5 speed conversion) as the labeling on the map files can be a bit confusing. the ecu is pictured below. thanks.

[Matt]

ECU is 23710-41P13 (Z32 VG30DETT AT USDM)

Documents\Nistune\ROM_Pack\Type2\Z32_VG30\Z32_VG30DETT_41P1F_AT_FP_maps.bin is your factory feature pack file on your PC

Your factory MAF is correct (Z32 MAF) still so that is okay. K constant slightly less than original (288) but not major

TIM reduced about 25% from factory for lareger injectors

Temperature enrich is incorrect (as mentioned before) and the cold idle gear timing tables are changed, along with a few other tables?

AT DTC is disabled? Vehicle is manual now? Disabling DTC does not change operation in this ECU, it just hides the errors only. Why is speed sensor changed? O2 sensor RHS probably should not be ticked either

Try going back to plain factory map with 370CC firstly and it should run fine. If it does not, there is something else going on

Even with the current tune, before changing injectors, load the 41P1F file, upload to the ECU, and just change TIM=448 and latency=850 only and see how that goes

[vanepico]

Might not be relevent to your problem, but 43psi fuel pressure at idle with the vacuum reference connected sounds pretty high doesn't it?

This site says it should be ~43psi at rest with the vacuum reference off, so a lot lower with vacuum.
https://conceptzperformance.com/wiki/in ... 20pressure.

On my CA18 i noticed when I put a 255 pump in, my fuel pressure increased a good 3 or 4 psi. I have a map sensor and an fp sensor logged through a DLP and when I datalog them I put the csv into excel and create a pressure differential column (fp - map), to check whether I am getting weird flow/bottleneck related fuel pressure anomalys.

[xlr8]

cool the 370cc's wont be here until next week so i will change fpr and reload the software and retune as you described and see what happens. dtc means diagnostic trouble code filter? i didnt know there was even an option to do that so i dont think i changed anything directly. but this car is a jdm spec right hand drive so i probably changed nistune to read mph instead of kph maybe that checks some dtc filters by default? and yes its swapped auto to 5 speed but i dont know how at dtc could have gotten checked off.

[xlr8]

fpr is changed, vacuum and ambient pressure are more correct now. i havent been able to test boost yet. didnt seem to help overfueling issues. i will grab the laptop and post the tune you recommended and log from it.

[xlr8]

hopefully you can see both wideband on this log as i see them fine on my end. i loaded and uploaded to ecu the file you stated with the lat. and tim changes only. still same issues super rich and mismatched. at temp it just struggles so bad to keep a 14.7 and still the random misfire. i did also try the a/c now it doesnt help much seems that was a random assist in the past. the stock injectors arrived today i will get them swapped as soon as i get time and re log with no changes on the tune.

8-29-2020-tunefrommatt.bin

(32 KiB) Downloaded 210 times

[Matt]

Can you interpret those gauges for us, rather than just post the pictures of them? I'm not exactly sure what I'm looking at here

Digital guages 33 and 44 PSI, when/where? Snapon analog 21 psi and 33 psi?

Okay in the log between 0- 79 degC we are seeing

2:15 Inj = 1.87ms / 1.87ms, AFR = 13.6:1
Gets richer as time moves on, but injection time has got leaner (as enrichment decays). Why is this?
9:18 Inj = 1.79ms/ 1.83ms, AFR= 11.8:1

Then at 9:34 all of a sudden AFRs changing for no reason? There is nothing in the ECU. So then the trims start moving

2020-08-30 17_19_10-Nistune [Z32(VG30DETT) Z32 (Type 2) Feature Pack 1.0 (Version_ 5)].png

(24.35 KiB) Downloaded 2438 times

RHS O2 sensor starts moving up/down and RHS trim goes to -8, but LHS reads rich still until 10:39 then LHS drops to -16

At 80 degC then both start normalising the fuel trims. Around 14.8 then

Cannot see LTFT RHS in the log file?

Do you see this still happen with both O2 sensors disconnected?

What if you change TIM = 512, and K Constant = 252 instead? How does that look?

[xlr8]

my apologies i thought i made it clear with the fuel pressure gauge pics, another forum member pointed out my fuel pressure regulator settings were too high at idle, so i adjusted it while using the snapon vacuum tester and nistune "fuel pump relay active" test function. since its running so rich when started its easier to set the fuel pressure this way without flooding the crankcase with fuel
i didnt try unplugging the o2 sensors this time i just did the warmup log, but ordinarily when i do the wideband readings are still inconsistant and same symptoms. i can do another log this afternoon following your suggested changes, and unplug o2's after warm so the differences are logged ?
i will wait to swap the injectors.

[xlr8]

with most recent recommended settings the engine was very hard starting then it started surging very high and low idle trying to die out and recover, i did log for a short time but it was so rich in the high 9's so i shut it off. i reverted to previous tune log (most recent forum upload) and the extreme surge was still there and eventually died. so strange since it ran fine (no surge) with that tune for the last log.
this car is all over the place.no changes to engine from last log, i will post the logs today in case helpful, but i dont know if it will provide much insight. i ticked LTFT on batt V off.
here is the short log for: base map file with only changes to LAT 850, TIM 512, and Kconst 252

[xlr8]

heres the base file with only changes: LAT 850, TIM 448

the engine died from rpm surging so low, though it was running fine from this tune previously.

[xlr8]

OK sorry for the delay we've had a relentless heat wave and I've been on mandatory overtime. I will get these deutchworks 370 cc installed with stock maps and see what happens.