RNN14 Pulsar strange issues.

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Re: RNN14 Pulsar strange issues.

Postby Matt » Wed Jul 12, 2017 10:38 pm

Sorry bigger posts like this take more time for me to read and respond... so they tend to get left to last. Particularly if I dont have the logs or BIN files with all information easily available to load and playback here

At this time I'm needing to re-reading the whole posts again trying to work out what the problem :(

Problem:
Either immediately after, or shortly after, (owner isn't sure), a hesitation developed between 2200 and 3000 rpm. If you're heavy on the throttle, it will pass right through the range with very little issue. If you're light with the throttle, there is very noticeable hesitation.

Z32 MAF, ID1000, vented BOV, fuel pump



If the Max load table is set high enough not to overrun, it shouldn't matter right? It looked really funny to me being at 255 for half the table.

This is done when automatically resizing the injectors so tuners don't accidentally hit the top clamp on TP limiting and wonder why when they add more fuel to the fuel map it isn't getting any richer.

I also have the issue where tuners using factory injectors don't use this feature (no injector resize) and hit the factory limits since they are used to the table being adjusted automatically when doing larger injectors

Doesn't it determine which load section of the fuel/timing tables get used vs actual load?

TP which affects total pulsewidth. I'm not sure on the TP indexing used in the maps (if that gets cut before/after indexing calculations) I would need to check that one

At present the stock turbo will never flow enough air to push beyond 150ish on the load scale, why scale all the way to 255? Or am I thinking of the wrong table?

255 is just a starting value, it is a clamp limit to help stablise (due to it being derived from airflow). You can lower it, but in the top end there is no point

Nistune doesn't give me the option to log Injector Duty Cycle.

Injector duty cycle is calculated from injection time and RPM. It will not log duty cycle as a parameter in itself (since the ECU doesn't report this). It should be displayed on playback (would need to check) if you have injection time and RPM within the software (but not the CSV file)

I deleted the Blow Off Valve in case it was leaking. No change. Also rechecked base timing, and fuel pressure. Both were solid

Ideally BOV should be fitted and vented in front of turbo (away from MAF)
Fuel pressure should be checked on boost (particularly where problem is occouring to make sure it is not dropping where you get hesistation)

Maybe I missed something but what is the cause of the hesitation? Are you getting bad AFRs in that particualr area, since we know the timing reported in the last trace I looked at was okay

Does this setting have anything to do with it? Hmm, guess Ill just have to try flattening it out. Either that or I can just disable overrun fuel cut I guess. More tests for tomorrow.

The deceleration min TPS should have nothing to do with the issue. As you mentioned at the start, you had these problems before installing the Z32 MAF and larger injectors. Somewhere along the line a problem was introduced

This table should not normally be altered as it will affect enrichment based on throttle position. I don't know from that particular post yet what your AFRs look like in the area (nor injection time) so I cannot add any comment which is why there is no response.


The only issue with that logic is, I have disabled o2 learning. You're describing the symptoms of a failing o2 sensor. This car behaves the same even with the sensor unplugged, and fuel trimming disabled.

Good that this is disabled in the meantime, helps eliminate one issue (and O2 analysis disabled with STFT/LTFT being clear and at 0%)

Matt, I had someone drive while I visually logged, since I can't get my computer to save ECUTalk logs.

Please use the logger inside Nistune (not other software) and record the hesistation issue, with RPM, MAF, TPS, O2, inj time, ign time, AFR etc logged and post here with your latest tune. I cannot see what is going on otherwise. and working from descriptions is too difficult

Any new theories Matt? Pretty much out of ideas

Please take logs of the issue (keep them short) and post with latest tune file. Email directly to me since I check forums about every 3 days at the current rate whilst I catch up on email backlog


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