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I can get a good AFR in OL although the idle is not steady it is +/- 200 rpms. The AFR hovers steadily around 14 +/- 0.5.
Once in CL, it goes lean 15-17.5 AFR.
I am kinda at a loss as to why. I have tried various things such as increasing MAF Table 1 values by 10-18%. 18% is too much and OL AFR suffers, 10% causes OL to suffer a bit less but has no effect on CL AFR.
I have tried using the pulse width listed on holley's site for my injectors, but the car actually runs worse with those pulse widths, than whatever random pulse widths were already in the bin.
I have set Single and Double fire mode to 42#/hrs.
I am including my bin, logs and decoder files in this thread.
Note I am not asking for anyone to operate on the bin, but simply including it so anyone that is willing to help has some reference point.
Additionally I run a modified bin, that accepts a WB input on pin D2 of the ECU. This allows me to read the WB data in Tuner Pro.
Tuned Performance has been helping me greatly with this, but has suggested we post here for additional insight.
I am flying out of town tomorrow (Sunday the 16th) but I will be checking this regularly while out of town. I won't be able to act on it until I return Wednesday the 19th though.
Thanks, below is a screenshot of my Tuner Pro Dashboard showing closed loop and lean.
Last edited by Green89IROC305; 06-15-2019 at 06:24 PM.
Between open loop and closed loop, usually the commanded AFR (cAFR) changes. This affects the injector PW as the cAFR is used in that calculation.
If the cAFR isn't in the data stream, check the injector PW change at the time the ECM goes closed loop.
Also, the INT & BLM should be looked at.
RBob.
Can the cAFR be changed. How is it commanded? What should I look for in in regards to PW?
I'm not sure if the cAFR is in the data stream or not but I will check.
Originally Posted by ULTM8Z
Do you have your NB on the opposite side of the engine from your WB?
No my WB is installed after the Y-pipe before the catalytic converter area in the intermediate straight pipe, so after both headers dump into a single source.
Thanks
Last edited by Green89IROC305; 06-16-2019 at 01:26 PM.
BLM never changes from 128, whether in OL or CL.
INT(Integrator) does tick down, but I am not sure what this means.
Target AFR is 13.88
When it is about at it's leanest 18.5 AFR, Injector base pulse width is 1.72
I am not relying solely on the ECU reading of AFR from the WB, but also the AFR gauge itself.
However the ECU is seeing the current state of the engine as Rich.
I wonder if something happened to my heated NB O2 sensor when the shop installed the new engine...
As to the Heated NB O2, I had a stuck open injector in my old engine and was running 10:1 AFR. I only backed it in and out of the garage, never drove it like that though., I wonder if that O2 is contaminated...
It seems to be swinging during OL though so I dunno.
I just ordered a new NB O2 and have plans to install it Thursday after I am back from my trip.
Below is a screen capture of the log.
Thoughts?
Last edited by Green89IROC305; 06-16-2019 at 06:33 PM.
Could try moving the narrow band to the other side and seeing what happens.
This could be some sort of split BLM issue common with short runner intakes. Such that the WB is picking up the results of a lean burn on the passenger side
Does this phenomenon only occur at idle or above idle too?
Could try moving the narrow band to the other side and seeing what happens.
This could be some sort of split BLM issue common with short runner intakes. Such that the WB is picking up the results of a lean burn on the passenger side
Does this phenomenon only occur at idle or above idle too?
I have not moved on to above idle much yet. But I remember my friend who was watching the guage when I opened the throttle from under the hood mention it went lean under revving in park.
nevermind, I am not reading the bin right, something is jacked up in tuner pro -> in other words, I loaded the log file in place of the bin. I had them similarly named in my Google Drive and grabbed the wrong one.. How dumb of me.
Last edited by Green89IROC305; 06-16-2019 at 06:55 PM.
After it goes into closed loop and goes lean, does it ever go back to normal target air fuel of 14-14.5 or so?
if you disable closed loop is air fuel good everywhere else in open loop mode? Thru part throttle and such?
how big is the cam?
I've not seen it correct itself, and being that lean on a new engine I was worried to run it much more than I did when it went that lean.
If there is no risk to the engine I am more than happy to give it a bit longer to see if it corrects itself.
I have not tried disabling closed loop just yet. I can do that at my next opportunity(Wed or Thurs). But overall at least at idle, AFR is pretty good in OL.
As to the cam, here is a link to the engine itself My Engine
I'm going to say that the injectors, while they may not be the problem, are an issue. Are you using injectors that are rated at 42# at 4 bar or 3 bar? A 42# injector rated at 3 bar is too big for your engine, assuming you have this engine: https://blueprintengines.com/collect...ock-bp38313ct1 If they are 42# at 4 bar that would come out to ~36# which isn't as bad but still not optimal. I'm using #30 3 bar injectors in my AFR headed 383 with a bigger cam and am fine. Your injector pulse width at idle of 1.51 mSec is too low for me to agree as being OK. When you get below a 2.0 mSec pulse width the injector doesn't want to respond in that linear and predictable fashion. I think your problem is that you are idling with an injector at 1.51mSec which is below it's linear range and when you are in closed loop the computer makes a calculation based on a linear calculation to take away whatever percent and it tries to take away that percent but in reality that amount of pulsewidth is way more/less so it just chases it's tail. If you are wanting to keep those injectors I would try to make the idle area an open loop area where fueling is concerned. A 30 or 32# injector would be easier to tune.
I'm going to say that the injectors, while they may not be the problem, are an issue. Are you using injectors that are rated at 42# at 4 bar or 3 bar? A 42# injector rated at 3 bar is too big for your engine, assuming you have this engine: https://blueprintengines.com/collect...ock-bp38313ct1 If they are 42# at 4 bar that would come out to ~36# which isn't as bad but still not optimal. I'm using #30 3 bar injectors in my AFR headed 383 with a bigger cam and am fine. Your injector pulse width at idle of 1.51 mSec is too low for me to agree as being OK. When you get below a 2.0 mSec pulse width the injector doesn't want to respond in that linear and predictable fashion. I think your problem is that you are idling with an injector at 1.51mSec which is below it's linear range and when you are in closed loop the computer makes a calculation based on a linear calculation to take away whatever percent and it tries to take away that percent but in reality that amount of pulsewidth is way more/less so it just chases it's tail. If you are wanting to keep those injectors I would try to make the idle area an open loop area where fueling is concerned. A 30 or 32# injector would be easier to tune.
I was afraid I would hear that. The shop that installed my engine chose the injectors not me. I was going to run 30 #/hr Bosch 3's but the ones I got had adapters for TPI and would not fit the HSR, so the shop chose these Holley Injectors. Keep in mind, they are not just a run of the mill shop, they are one of the highest rated performance shops in my area.
As to them being 4 bar or 3 bar, I am unsure, perhaps something at that link could illuminate it for me. But yes that is my engine you linked to. I can always have them switch out the injectors as well.
As to the response time, in OL I am hovering around 2.5 pulse width, its once in CL the ECM starts yanking out fuel like crazy and the pulse width drops.
The below image is shortly before CL happens.
Last edited by Green89IROC305; 06-16-2019 at 07:59 PM.
I was afraid I would hear that. The shop that installed my engine chose the injectors not me. I was going to run 30 #/hr Bosch 3's but the ones I got had adapters for TPI and would not fit the HSR, so the shop chose these Holley Injectors. Keep in mind, they are not just a run of the mill shop, they are one of the highest rated performance shops in my area.
As to them being 4 bar or 3 bar, I am unsure, perhaps something at that link could illuminate it for me. But yes that is my engine you linked to. I can always have them switch out the injectors as well.
Those injectors that you linked to are a 3 bar injector as they are rated at 42# at 43.5 psi of fuel pressure. They are too big.
You could use them but it would mean creating a bin with an open loop fueling idle region. To me, swapping injectors injectors to a smaller size is a much easier solution.
I wont say its injectors. I ran 42’s in my 383 just fine but they were lucas 42’s
however i ran into a similar problem as what you described
my open loop was tuned fine. When i enabled closed, on initial start ups as it transitioned to closed loop, it went lean til it almost shut off but then normalized to stoich as commanded. I never did get to the bottom of it and kept it open loop. However it was suggested that it may be closed loop timers, maybe need to lengthen them to keep sensor hot even tho its a heated o2.
I do believe longtubes cool gases down a bit by the collector and may take more time to heat sensor.
Also cam overlap could fool o2 sensors some and may read leaner than actual. But that cam isnt giant by any means
at idle i would see if it goes lean and then back to normal. Or if it normalizes with some throttle in park/neutral
Holley offtimes are not pulsewidth correction values in 6E i dont believe
i basically used stock AUJL table in mine but around the 12.8 and 14.4 table values i made them the same.
Are you saying then, that the values on Holley's site(attached below) are not what should be in this table(also attached below)?
If so, that would explain why I suspected it of running better with the stock values for the table "Injector pulse width correction vs Battery Voltage"
Actually i think it may be the same. We used to call it offsets but now people are using off time or dead times. Probably the same thing. I just know close to the stock settings seemed to work ok for me, and i used alot of timing advance at idle to stabilize idle. My cam was pretty big and tight lsa
I talked to the installer of my engine and they are willing to swap the injectors if I feel strongly enough which I do. What size should I get them to install. I've heard varying sizes 30, 32, or 36.
if I could get a definitive answer that would be much appreciated thank you for everyone support.
30 or 32 would be fine and they are readily available in the Ford world. I think that without a datasheet for the injectors 400 rear wheel horsepower is the minimum for 36# injectors.
30 or 32 would be fine and they are readily available in the Ford world. I think that without a datasheet for the injectors 400 rear wheel horsepower is the minimum for 36# injectors.
Thanks, I'll work with them to get the right size.
I swapped my injectors out to 36#, I know most recommendations were 30-32#. However it's running great, a tad lean atm, but I can correct it. Thank you all for your support in this matter!
06-15-2019, 01:45 PM
