3SGTE Idle Setup, Fuel VE Table

[INSW20]

I have my new G4+ running as of a few days ago and working on getting idle sorted out.  Is there anything that seems way off in my current settings or idle log?

I disabled IAT fuel correction since I'm running modeled fuel with a FP sensor, but it seems like my VE table for fueling is super high on table 2 in the idle area?  I'll be running full flex fuel, tank is currently filled with E75, so I am mainly tuning table 2 and tried plugging in ~70% values in table 1 until it gets to the tuner.

My fuel blend ratio is linear 0-100%, but since I will never fill with E98-E99, I set my fuel table ratio to 100% table 2 at 80% ethanol content.  Am I making sense in doing so?

Thanks!

 

3SGTE Idle Log - 12.27.2020.llg3SGTE 1991 MR2 12.27.2020.pclr

[INSW20]

Specifically looking at my charge temperature vs IAT reading, would this discrepancy be causing such high VE table values?  I'm using a phenolic spacer on my intake manifold, IAT sensor is just upstream of the throttle body.  Do I need to change my charge temp approximation table?

 

 

[INSW20]

If it helps, these are brand new ID1050x's, and my FPR is slightly undersized compared to my fuel pump output, but my understanding is that should all be accounted for by the fuel model, using differential pressure to adjust fueling.  I zero'd out my charge temp approximation table, warm up enrichment, etc...  I'm still getting around 80% VE at idle, and I'm still lean.  What else am I missing?

My understanding is that we should see closer to 50% VE at idle.

 

 

[Ducie54]

Your base fuel pressure is 440kpa so your injector data has to match that. Or drop your base fuel pressure down to 300kpa

[INSW20]

I can't drop my base pressure, so should I split the difference of these two tables?  I was under the impression the model would adjust for fuel pressure, or that the higher base pressure would cause my VE table to be lower?  But I'm probably misunderstanding things.

 

 

[dx4picco]

you can make a 3D table for your dead times. leave battery volts on X and put differential fuel pressure on Y with 300 400 and 500 kpa break points and then give the raw values from there. the link will then do the interpolation according to the fuel pressure it reads.

[INSW20]

Something like this?

 

 

 

And what would I set my injector flow rate and rated pressure at?

So with some rough math, I'm seeing flow rates around 1310cc/min at 440kpa differential pressure:

Pressure (kPa)	135.0	200.0	300.0	400.0	440.0	500.0	600.0	700.0
Flowrate (cc/min)	690.2	857.8	1066.3	1235.7	1310.0	1369.2	1468.0	1577.2

It's not quite linear, but this value seems to fit pretty well with the rest of the curve.

[dx4picco]

Yes, like this table. 

 

Either you put 1300 at 440 or you leave 1060 at base pressure (300) and ECU makes the correction himself when FP is changing

[INSW20]

Those changes seem to have helped tremendously!  My fuel VE table is just about 70% at idle now at 1.05 lambda, and the engine seems happy idling there hot.  Thanks everyone for all the help!  If anyone has any further suggestions, I'd be happy to hear them. 

 

[INSW20]

Here's the update on where it stands with cold start and idle.  I have a couple small adjustments I think I need to make on initial startup and warmup enrichment.

Other than that, do I understand the VE table that the entire columns should be the same value more or less?  I know there will be minor variations in VE due to changes in backpressure under boost and things like that, but overall should be relatively close?

I believe I need to wait to tune accel enrichment until after the map is complete, but is there anything else I should look at before taking it for tuning?

 

 

 

 

[Adamw]

7 hours ago, INSW20 said:

Other than that, do I understand the VE table that the entire columns should be the same value more or less?

Generally VE will be lower at lower loads since the closed throttle restricts cylinder filling.  

But otherwise the basic set up looks ok.  Copy the charge temp table example from the help file as a decent starting point. 

Generally for flex fuel you would tune on an un-blended fuel first (usually petrol), then the highest ethanol blend you will run (or pure ethanol) secondly.   

[INSW20]

Perfect, thank you!

Yep, I just wanted to get it running with what was in the tank, and once it goes to the tuner I'll let them take it from there, whether they want to tune petrol or E85 first.  I figure the more I can get set up reasonably well before getting there, the less hours I'll get charged and the more they can focus on the mapping and more complicated feature setup.

[koracing]

I find it much simpler to tune petrol first, and once you tune whatever blend of ethanol and petrol you want, it is possible to extrapolate the 0% and 100% tables linearly in excel (assuming you use the same axis breakpoints on table 1 and 2).  

[INSW20]

Yep, if the tank weren't already full of E85 (77%) then I would have started there.  I'll just get it as far as I can and then let the actual tuners take it from there.  Thanks!

(Also, can't thank you enough for these Spearco IC pipes!  )

[koracing]

I've got some pretty decent startup setttings for a car here I'm running on 77% ethanol that I've been getting good cold starts out of down to 35°F ambient temps in the last couple weeks.  It's got 1000cc Bosch injectors (from Fuel Injector Connection). 

Personally I've switched to using the AFR lambda overlay map for cold start enrichment and the warm up enrichment table is largely zeroed out.  I just set the AFR to subtract from target at lower ECT using modelled fuel equation.  In addition to that, it becomes possible to use closed loop from the minimum of 32°F (0°C) if one so desires.

[INSW20]

2 hours ago, koracing said:

I've got some pretty decent startup setttings for a car here I'm running on 77% ethanol that I've been getting good cold starts out of down to 35°F ambient temps in the last couple weeks.  It's got 1000cc Bosch injectors (from Fuel Injector Connection). 

Personally I've switched to using the AFR lambda overlay map for cold start enrichment and the warm up enrichment table is largely zeroed out.  I just set the AFR to subtract from target at lower ECT using modelled fuel equation.  In addition to that, it becomes possible to use closed loop from the minimum of 32°F (0°C) if one so desires.

That's excellent advice, I'll check that out and hopefully come back soon with good results.

[ellisd1984]

3 hours ago, koracing said:

I've got some pretty decent startup setttings for a car here I'm running on 77% ethanol that I've been getting good cold starts out of down to 35°F ambient temps in the last couple weeks.  It's got 1000cc Bosch injectors (from Fuel Injector Connection). 

Personally I've switched to using the AFR lambda overlay map for cold start enrichment and the warm up enrichment table is largely zeroed out.  I just set the AFR to subtract from target at lower ECT using modelled fuel equation.  In addition to that, it becomes possible to use closed loop from the minimum of 32°F (0°C) if one so desires.

Can I ask what sort of settings you've got in your dead times and short pulse width tables for bosch 1000cc injectors?  I'm chasing my tale trying to get my car idling at any sort of consistant Lambda (celica 205 gt4 on petrol)  The deadtimes i got supplied don't seem to be anywhere near and I can't switch the injection to batch fire to check as the car just runs even rougher! 

What's the lowest actual & effective pulsewidth that work on the 3sgte with similar injectors? As soon as my coolant fans cut in (or any sort of electrical load)  my afr's just go through the roof. 

[INSW20]

FWIW, I'm getting a PW of 2.449 with an effective PW of 1.520 on mine with a stable idle lambda, using ID1050x's.

[Ducie54]

What lambda at idle? Try at .95 and see how that goes. Once u get accurate dead times you can lean it back out. 

4 hours ago, ellisd1984 said:

Can I ask what sort of settings you've got in your dead times and short pulse width tables for bosch 1000cc injectors?  I'm chasing my tale trying to get my car idling at any sort of consistant Lambda (celica 205 gt4 on petrol)  The deadtimes i got supplied don't seem to be anywhere near and I can't switch the injection to batch fire to check as the car just runs even rougher! 

What's the lowest actual & effective pulsewidth that work on the 3sgte with similar injectors? As soon as my coolant fans cut in (or any sort of electrical load)  my afr's just go through the roof. 

What lambda at idle? Try at .95 and see how that goes. Once u get accurate dead times you can lean it back out. 

[ellisd1984]

6 hours ago, INSW20 said:

FWIW, I'm getting a PW of 2.449 with an effective PW of 1.520 on mine with a stable idle lambda, using ID1050x's.

Is this running ethanol though?  This will mean you're runnning a higher pulsewidth than just petrol/gasoline

[ellisd1984]

6 hours ago, Ducie54 said:

What lambda at idle? Try at .95 and see how that goes. Once u get accurate dead times you can lean it back out. 

What lambda at idle? Try at .95 and see how that goes. Once u get accurate dead times you can lean it back out. 

I've started another threed as I don't want to hi jack this one, thanks for the reply
 

 

[INSW20]

I've moved in the wrong direction slightly.  =(

It seems like I'm getting a lot of kickback during cranking (this has been common ever since I got it running).  I have noticed several backfires that heat my IAT sensor (mounted in TB inlet) enough to kick my intercooler fan on (set to 120F threshold).  I tried lowering my cranking ignition timing to 5* with no real difference, other than it seemed worse.

My best log so far for starting is from Tuesday's post (3SGTE Startup Warmup Idle log) .  Attached is one from tonight that wasn't as smooth.  It looks to me like it needs more crank enrich, and more post-start enrich.  Aside from that, what am I missing?  What else could be causing so much kickback and backfires into the intake?

Thanks for all the help!  Once I get the start a little better I'll be trailering it to the tuner (200 miles away).

 

[Adamw]

Got a log of this "kick back", that would more likely be a trigger issue than fuel.  

[INSW20]

I haven't seen anything that I can see in the logs that shows it, but I will adjust my trigger arming thresholds.  Looking more closely at the log, it looks like I'm cranking for almost .5 seconds before any RPM is registered in the ECU.  I'm basing this off when battery voltage drops compared to when I first see the engine speed jump to 264rpm.

So it's reasonable that anywhere from 5-20* BTDC ignition timing would be acceptable for E85 cold start?

EDIT:  My trigger 1 threshold is .2V at 0rpm and .5V at 1000.  Trigger 2 is 0.5 and 1.0, respectively.  I'll adjust 2 down and see if that helps.

Another edit:  It's showing trigger errors.  Is there no error counter for Trigger 2?  I just read that the trigger error covers both, since if there's a problem with either trigger it'll increment the error count.

[INSW20]

It cranked over SO. MUCH. better after adjusting the trigger threshold for trigger 2.  No kickback, no backfires.  It still took just over 2 seconds of cranking, but I think that's now down to my enrichment/CLL needing further polishing.  And still seems like it's not horrible for E85 on a cold start, 55F, on non-optimized fuel and ignition maps.