Hondata Fuel System

[MoTeC R]

Haha going back to work Monday after messing with it Saturday afternoon and Sunday morning sucks. My body hurts and I've got cuts all over my hands (stupid factory zip ties). I hit my head on parts of the hood to multiple times climbed up in there, so I have bumps and cuts to show there. I could a got a blanket and put the hood all the way back and tied it, but it was good shade from the sun

I would highly recommend the $500 on the Flex Fuel kit unless you don't have enough stations near by to justify it. It definitely makes a noticeable difference running e85 vs 93 or mix. Not just on the dyno it's a noticeable difference in power while driving.

Glad you got it all sorted and have some battle scars it sounds from the process.

Sponsored

 

[kefi]

Corn juice is a godsend, even on factory fuel system.

 

[AdamD19DFK8]

Here's a log where afr is really rich.. like 27.1PSI @ 4850rpm at 11.8:1 I think during the long pulls DIFP duty only goes to 63%





and heres the calibration

I think I copied and pasted the wrong set of ignition table maps that I have saved. I take the maps from the PRL dp/ic basemap and go from there. I think I used a conservative one by accident.

Either way, I'm gonna crank up top end timing until I get KR, try to get a pattern,. And enrich the area. Try to increase it more and test some good pulls. Gotta find that sweet spot where adding more timing doesn't add power. That's really hard without a dyno though. I could also try and lean out the afr more down low to mid low to see if that adds to it. I need another weekend of testing.

My car doesn't like EGT disable for some reason. If you take the exact tune I posted here, and in mods check the disable egt reduction mode, it will run really lean while cruising around stutter and backfire and feel like it's constantly engine braking harder than the car could ever engine brake lol. It's really annoying to drive, I was going to hit the highway but spirited driving the back roads didn't inspire much confidence when using slight throttle. My log didn't record right so i only have 6 minutes of light driving to show for it yesterday. I've noticed this behavior on the highway too before when I tried to use egt disable and the car will crack and gurgle like crazy.

I was really afraid something with the manifold was loose like an evaporation hose or the manifold itself. Like it was getting too much air for the fuel mixture. Go and reflash with the mod off and it drives like a dream. I have to check my flashpro and comb through all the datalogs on it since I only saved a couple



The pulls in this video are in the log, near the end where i get off the highway.

This weekend I could try messing with an E85 pump. Some royal farms around me have it. It'll be a fun like experiment. Obviously lower air charge limits

 

[Jpierro79]

Here's a log where afr is really rich.. like 27.1PSI @ 4850rpm at 11.8:1 I think during the long pulls DIFP duty only goes to 63%





and heres the calibration

I think I copied and pasted the wrong set of ignition table maps that I have saved. I take the maps from the PRL dp/ic basemap and go from there. I think I used a conservative one by accident.

Either way, I'm gonna crank up top end timing until I get KR, try to get a pattern,. And enrich the area. Try to increase it more and test some good pulls. Gotta find that sweet spot where adding more timing doesn't add power. That's really hard without a dyno though. I could also try and lean out the afr more down low to mid low to see if that adds to it. I need another weekend of testing.

My car doesn't like EGT disable for some reason. If you take the exact tune I posted here, and in mods check the disable egt reduction mode, it will run really lean while cruising around stutter and backfire and feel like it's constantly engine braking harder than the car could ever engine brake lol. It's really annoying to drive, I was going to hit the highway but spirited driving the back roads didn't inspire much confidence when using slight throttle. My log didn't record right so i only have 6 minutes of light driving to show for it yesterday. I've noticed this behavior on the highway too before when I tried to use egt disable and the car will crack and gurgle like crazy.

I was really afraid something with the manifold was loose like an evaporation hose or the manifold itself. Like it was getting too much air for the fuel mixture. Go and reflash with the mod off and it drives like a dream. I have to check my flashpro and comb through all the datalogs on it since I only saved a couple



The pulls in this video are in the log, near the end where i get off the highway.

It’s not the egt delete it’s an issue with map loading. I’ve had the same issue where it targets 14.7 under boost but reads 12.4 on fueling charts. In order to fix this you need to return the car to stock start it then turn off. Disconnect the battery 2 minutes with door open. Build a new tune from scratch. Copy and paste your chart values Most likely your egt deiete tune is corrupted during flash. I’ve had it happen twice now both times after an update to hondata and firmware update.

what will happen is it will go in and out of targeting fuel it will bounce back between 14.7 and your afr target in fueling charts. It will swing as lean as 15.8 under boost.
rebuilding the tune is not bad. I have the logs that I need to send to hondata to BBC show them.

 

[MoTeC R]

I’m only running 25PSI and the torque is peaking around 5300 on e85. I’m tuned from a very hot day on the dyno in July. I may do the 2.3L engine build prior to the P600 release (likely early next year is I’ll my assumption). Getting the build done this winter will allow me to be ready to just drop the turbo in and avoid lengthier delays if PRL doesn’t release their turbo until spring. That way I’ll be ready to drive in the nicer weather sooner than later if the turbo is delayed beyond winter.

 

[AdamD19DFK8]

It’s not the egt delete it’s an issue with map loading. I’ve had the same issue where it targets 14.7 under boost but reads 12.4 on fueling charts. In order to fix this you need to return the car to stock start it then turn off. Disconnect the battery 2 minutes with door open. Build a new tune from scratch. Copy and paste your chart values Most likely your egt deiete tune is corrupted during flash. I’ve had it happen twice now both times after an update to hondata and firmware update.

what will happen is it will go in and out of targeting fuel it will bounce back between 14.7 and your afr target in fueling charts. It will swing as lean as 15.8 under boost.
rebuilding the tune is not bad. I have the logs that I need to send to hondata to BBC show them.

For me it commands the same afr as usual but The engine runs lean. Afr command or actual AFR don't bounce around or deviate any, it's just the actual AF graph mimics it's command only +2-3 more parts air, if one changes, the other changes by the same amount, it's just the actual mixture is lean.
It doesn't have this behavior at WOT at all, just below 50% throttle usually at lower rpm

Fuel trims are within 5% too

 

[kefi]

My car doesn't like EGT disable for some reason. If you take the exact tune I posted here, and in mods check the disable egt reduction mode, it will run really lean while cruising around stutter and backfire and feel like it's constantly engine braking harder than the car could ever engine brake lol. It's really annoying to drive, I was going to hit the highway but spirited driving the back roads didn't inspire much confidence when using slight throttle. My log didn't record right so i only have 6 minutes of light driving to show for it yesterday. I've noticed this behavior on the highway too before when I tried to use egt disable and the car will crack and gurgle like crazy.

If that's true and you can replicate it that easily, that's pretty serious and you should report it to @Hondata.

 

[AdamD19DFK8]

If that's true and you can replicate it that easily, that's pretty serious and you should report it to @Hondata.

Yeah it's puzzling, the car performs like usual at WOT but not at lower loads. I'll try to replicate it this evening plus look through other logs I have where something very similar was happening though not as seriously at highway speed, at least by feel I'll have to check fuel data to see if it's running leaner than what the ECU is calling for.

I might just manually change around the pa temp table and try to increase air charge manually.

I'll be able to expand on this after work when I can test it

 

[Jpierro79]

Yeah it's puzzling, the car performs like usual at WOT but not at lower loads. I'll try to replicate it this evening plus look through other logs I have where something very similar was happening though not as seriously at highway speed, at least by feel I'll have to check fuel data to see if it's running leaner than what the ECU is calling for.

I might just manually change around the pa temp table and try to increase air charge manually.

I'll be able to expand on this after work when I can test it

Here’s you proof commanding 14.7

here’s the fuel chart what it’s supposed to command. You can put 11.8 across all of it it’s still going to get lean

there were zero changes to the tune except a 5 percent increase in aircharge and an update. After that no matter what o changed if I used the same starting file even after modifying it did this till 4800 rpm then starts fueling correctly. It is 100 PERCENT A FLAW In flashing. I’ve done enough tunes on different cars to see crazier crap than this.
same exact file copied values to a new file fixes it along with ecu return to stock. Until you return ecu to stock it probably won’t go away. You can try disconnecting the battery.

There’s no reason for the egt limit to cause this. It doesn’t do anything except chose fueling charts. Higher egt selects Minimum lambda table to cool down cylinder temps. If that chart is identical to the others and it exceeds temp it removes boost. It has absolutely nothing to do with your set up at all. It’s physically impossible to cause lean.

What happens is the ecu gets stuck between the initial learn mode and closed loop fueling. It The reason it locks on 14.7 is to set base fueling. It’s basically checking upstream lambda sensor calibration.
You should know that for about a mile or two the afr is locked in on 14.7. Once it starts moving it should continue to follow what you set in fueling charts. Again egt has nothing to do with fueling offset at all. Only boost limit and which chart fuel it uses.

at first I suspected MAF sensor failure but checking the MAF voltage increase showed a smooth incline.
hers a pic of MAF curve

as you can see there’s no reason for it to fuel lean. If I load the old file which I did as an experiment verification it screwed up all over again.
Both times it happened to me after an update where it reloaded the tunes to my flashpro after a firmware update. I even deleted them out of the flashpro and reloaded them but didn’t rebuild them.

I’m an auto tech diagnostic 21 years been tuning 6 years and built computers throughout the years. I’m 100 percent positive it’s a map file loading issue: whether the update caused it or not can’t confirm. It might be cause if you think about it if the update changes coding in the tune it’s very possible in an old coding it could put an incorrect value into the code. If you accidentally add a single space and n coding you can ruin the whole tune.

I had a tune load using hptuners that cause one half the engine to run at 16.0 at idle and the other half at 14.2. Dissconnected the battery problem solved. It happened only once and no matter what tune I loaded it did it. It’s not uncommon during ecu flashing to get corrupt file. There are many factors. I’ve dealt with programming factory ECUs which is a far more dangerous procedure cause you can very easily brick a computer.

All ecu values in log were on point. Iat iat2 ect ect2 map sensor MAF sensor diff fuel pressure and diff pressure command. Cam positions and vtec activation. It caused knock retard but that’s from lean. It just gets stuck on 14.7 at WOT until 4800 rpm fir absolutely no reason. Egt or not. Doesn’t matter what codes you deiete or don’t doesn’t matter what egt limit you set. Fuel trims don’t fix it. It’s essentially a memory jam like you get with any normal computer that require restarting to clear what’s jammed in the memory. It is just a computer. It does not restart every time you turn the car off. It only goes into sleep mode essentially. That’s why battery disconnect is required to fix it.

 

[Centripetal]

I wonder if there's something up with the cat-protect temperature and disabling EGT. From what Hondata said, the cat protect temperature is lowered to make it run less lean. Consequently, I can see why that works because lean EGT is hot, so you rich it up to lower the catalyst temperature. I seem to recall reading somewhere that the fuel re-learn procedure will not complete if EGT is too high, which makes sense because the O2 sensor and catalyst are not at their ideal temperature range. Maybe I'm remembering another car.

 

[AdamD19DFK8]

I don't have a cat and my engine bay temps don't get hot.

Here's the brief clip I have of it acting wonky

 

[Centripetal]

I don't have a cat and my engine bay temps don't get hot.

Here's the brief clip I have of it acting wonky

You may not have a cat but far as the ECU is concerned, you have a cat and it has a temperature.

 

[kefi]

I may do the 2.3L engine build

calm down satan, don't make us look that weak

I wonder if there's something up with the cat-protect temperature and disabling EGT. From what Hondata said, the cat protect temperature is lowered to make it run less lean. Consequently, I can see why that works because lean EGT is hot, so you rich it up to lower the catalyst temperature. I seem to recall reading somewhere that the fuel re-learn procedure will not complete if EGT is too high, which makes sense because the O2 sensor and catalyst are not at their ideal temperature range. Maybe I'm remembering another car.

The Bosch ECU has it's own way of determining the A/F target that isn't entirely understood. From factory it will target stoichiometric (14.7:1) near constantly until the catalytic converter reaches a certain temperature, at which point it starts using some static tables for fueling.

Hondata gives us direct control over the A/F by setting the catalytic protection temperature to 400F so these tables are used constantly once the engine has warmed up a little. That's why the tables have 'cat protect' in their name.

However, Hondata's basemaps all use the factory cat protect tables as-is.

 

[Centripetal]

calm down satan, don't make us look that weak


The Bosch ECU has it's own way of determining the A/F target that isn't entirely understood. From factory it will target stoichiometric (14.7:1) constantly until the catalytic converter reaches a certain temperature, at which point it starts using some static tables for fueling.

Hondata gives us direct control over the A/F by setting the catalytic protection temperature to 400F so these tables are used constantly once the engine has warmed up a little. That's why the tables have 'cat protect' in their name.

However, Hondata's basemaps all use the factory cat protect tables as-is.

Close loop operation with O2 sensor is known. You'll notice when you're idle air fuel will search, which is in control loop narrowing down on control. The important part of that control driving under load is is the fuel-learn (aka basic calibration) can be done. If it cannot, it will search under load as well.

 

[AdamD19DFK8]

You may not have a cat but far as the ECU is concerned, you have a cat and it has a temperature.

Ok, but what's your point? the sensor reads cooler after the end of a 4th-5th pull because I have it super rich