[pazi88]

440cc is quite small for 2,5l engine. Well for NA those are unnecessary big, but in turbo engine 440cc is actually puny size and doesn't stretch to higher HP number. I have personally used 870cc injectors in BMW 2.8litre engine with speeduino without any problems.

If the VE values are too low at idle, just adjust Req. Fuel lower that you can run about 30 VE at idle.

[LPG2CV]

@tal_s24
Still waiting for your log in msl format

[Tal_S24]

I have an idea how to start eliminating possibilities.

Do you have any gama enrichment showing added fuel when it is at idle?
If not then a lot of things can be left out.

There are things that do change gama enrichment.
...
Hope you get it solved soon so you go on to the next part of tuning.

It is all fun until it is frustrating.

Black Knight

Hey, thank you and thank all of you for trying to help me figure it out

440CC injectors personally pulled off of a 2JZ engine, they're 440CC which as said by others is nothing - I actually have 1050CC injectors coming to support more than the 166kpa Im currently maxing fuel at.
Gamma enrichment is at 100% when idling so it isnt an enrichment issue that I can see
O2 calibration is okay, It shows the same number on the AEM gauge as it does on Tunerstudio, and even if it wasnt the problem is that I can't really adjust the AFR at all. Even if it was 12.5 and not 12, it still only would go from around 12 to 17 when idling. The fuel pressure is steady, fuel pressure regulator is okay and it isnt connected to vacuum for that exact reason.
I'm really lost as to what's going on here.
Setting a higher Req fuel does make it better but then at higher RPMs and boost it would go to quite high numbers. Currently on 166 KPA it is around 70-80 VE, idle is at 5. If I halve the req fuel I would go to around 220 VE when Ill get to the 270kpa boost Im aiming for.

Above 60 KPA & higher RPM it's quite easy to accurately adjust the AFR, it only happens around idle.

Take a look at this video, this guy is tuning his table so accurately on his turbo Civic while still having decent VE numbers up high. If my req fuel would be 10 times smaller I would'nt reach that VE values on idle and my VE values on boost would be 700

[Tal_S24]

@tal_s24
Still waiting for your log in msl format

Sorry!
Do I have to make a new one or can I somehow convert the old one for you?

[LPG2CV]

I would suggest you do a new log. Just warm it up and let it idle. Be a good idea to post the current tune with it as well.

[ric355]

The idle is absolutely terrible. Wet and smelly on 11.8 and it barely runs on 16.7.
I've used another wideband previously (14point7) and now using an AEM X-Series, both showing pretty much the same AFR

What pulse width are you getting at 11.8 vs 16.7?

@Tal_S24 you didn't answer this question. The answer would be in your logs but as we can't open them...

[Tal_S24]

The idle is absolutely terrible. Wet and smelly on 11.8 and it barely runs on 16.7.
I've used another wideband previously (14point7) and now using an AEM X-Series, both showing pretty much the same AFR

What pulse width are you getting at 11.8 vs 16.7?

@Tal_S24 you didn't answer this question. The answer would be in your logs but as we can't open them...

I'll get a new log tomorrow. The tune is the same

[Black Knight]

440cc is quite small for 2,5l engine. Well for NA those are unnecessary big, but in turbo engine 440cc is actually puny size and doesn't stretch to higher HP number. I have personally used 870cc injectors in BMW 2.8litre engine with speeduino without any problems.

If the VE values are too low at idle, just adjust Req. Fuel lower that you can run about 30 VE at idle.

Thank you for this posting.

I am still learning more about base tune and tuning.

This info on required fuel is of big help for me and it may help everyone that is not familiar with it.

I will now try a different required fuel to get my idle ve numbers up and if I understand what you said, I should have higher ve numbers and that should reduce the twitchy over sensitive fuel change problem at idle.

Can I assume that this could also make all of the VE table less twitchy?

I will try this today.


Thanks

Black Knight

[Black Knight]

I have an idea how to start eliminating possibilities.

Do you have any gama enrichment showing added fuel when it is at idle?
If not then a lot of things can be left out.

There are things that do change gama enrichment.
...
Hope you get it solved soon so you go on to the next part of tuning.

It is all fun until it is frustrating.

Black Knight

Hey, thank you and thank all of you for trying to help me figure it out

440CC injectors personally pulled off of a 2JZ engine, they're 440CC which as said by others is nothing - I actually have 1050CC injectors coming to support more than the 166kpa Im currently maxing fuel at.
Gamma enrichment is at 100% when idling so it isnt an enrichment issue that I can see
O2 calibration is okay, It shows the same number on the AEM gauge as it does on Tunerstudio, and even if it wasnt the problem is that I can't really adjust the AFR at all. Even if it was 12.5 and not 12, it still only would go from around 12 to 17 when idling. The fuel pressure is steady, fuel pressure regulator is okay and it isnt connected to vacuum for that exact reason.
I'm really lost as to what's going on here.
Setting a higher Req fuel does make it better but then at higher RPMs and boost it would go to quite high numbers. Currently on 166 KPA it is around 70-80 VE, idle is at 5. If I halve the req fuel I would go to around 220 VE when Ill get to the 270kpa boost Im aiming for.

Above 60 KPA & higher RPM it's quite easy to accurately adjust the AFR, it only happens around idle.

Take a look at this video, this guy is tuning his table so accurately on his turbo Civic while still having decent VE numbers up high. If my req fuel would be 10 times smaller I would'nt reach that VE values on idle and my VE values on boost would be 700

Wow. Good thread. Much learning going on.


I think you have two problems in conflict with each other.

I just learned about ve value to req fuel. very good stuff.

Now you get req fuel to help out at idle but you say your ve numbers will be 770 under boost. I hope that was not real. That number is very high.

I had with an NA motor at 80 to 100 kpa ve numbers as high as 180 and as low as 12 on ve at idle.

That swing was because my O2 lambda delay was way off. I found that by getting the delay dead on my table was much flatter. No wild high numbers under load now.

I got my lambda delay right and now I will try a different req fuel number to get the idle numbers up to reduce the twitchy tuning.

I will post later on what I find.

If you need help on lambda delay I will post an easy way to find it on another thread to help more people on the forum. Yes, I have found an easy and accurate way to find delay.


Thanks to all of you.

Black Knight

[Black Knight]

Had a good day with the ECU.

Req fuel did make a good change. Got the VE numbers up and it did make tuning at idle better.
It also seemed to stop most of the AFR gauge drift. Gauge was more stable like more sensor filter.
I did not get to road test this as I had another project to finish today. I got an EGT to record data on TS and MLV. I also now have an EGT gauge on TS.

The EGT was helping me see what req fuel was doing. Both AFR and EGT changed when I changed req fuel.

Very interesting.

Now for a question.

Req fuel did what you said but I have done similar with inj CCs and got similar results.
The I did not know it would help the low end tune I used it as part of finding and setting inj dead time.

I noticed that req fuel will not change inj CCs but changing CCs will change req fuel.

Is one way better than the other?

I will try both tomorrow.

Good thread and good info.

I will spend less time talking about my project so as not to be high jacking this thread.
Sorry if I did.

Hope my test and sharing help you.

Thanks

Black Knight