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I loaded v3.43 software last night. I manually entered all values from a fresh .msq to match my old setup with v3.23 and now the PW's seem to be way longer than they used to be (was ~4ms at idle, now ~32ms). I've looked thru all settings and checked out a datalog and all gamma enrichments seem identical and MAP and RPM are identical so I am not sure how this is happening. Any ideas? could it be the new software?
BTW- my cold start issue (car wouldnt start with cranking RPM below 140 RPM) went away with this new v3.43 software somehow.
Any assistance would be greatly appreciated. My apologies in advance if it's just something dumb I overlooked
The revision notes for changes on v3.43 specify:
Old Equation:
Pw = Topen + MAP x VE x ReqFuel /
New Eq (model-based):
Pw(sec) = Topen + ((MAF(g/s) x (120 / Rpm) / No_cyl) / AFRTGT) / InjFlowRate(g/s)
In reviewng my Datalog, the PW is most definitely the problem in my case. For example, idling at ~850 RPM, ~40 kPa I think my map is in the area of VE = 40%. This means with a ReqFuel = 18mSec, my PW should be ~7.2mSec. My PW in this general range is around 30mSec.
I am running MAP only, I would assume if I selected MAP only (no MAF) it would use the old equation, is this not true anymore?
Nothing stands out at the moment. I will test this when I get a chance, probably tomorrow. But to answer your question - if you are using MAP only, then Yes, you should get the same PW compared to 3.23 code. The new PW eq is only for MAF.
I ran your msq and immediately got a 32 ms (max possible value). To get things to come out correct, I had to set AFRStoich = AFRTarget = 0.45 volts and change "Separate VE & AFR table w/ WB EGO" to NB EGO. This necessitated some changes to the ini file. I am still working on this and will send you something tomorrow.
Ok I think I have a modified ini file and msq file that should give you a reasonable PW. Basically several things got clobbered in the msq and I made some changes to the ini file to hopefully reduce the chances of this happening. The main problem was that the pw was getting multiplied by AFRStoich/AFRTgt, which had a mix of afr/ volts which jacked the PW up by about a factor of 10. Also there was some ambiguity in the msq as to whether you had a WB Innovative or a NB, as specified by the EGO Type. I set it up as a NB but you can of course change this if it is wrong.
I'm still having the same problem with the NB settings but here's the thing- I do not have an o2 Sensor hooked up. I have an innovate WB but I only use it to setup my VE table then pull it so that I can use it on other cars so in normal operation I do not have an o2 sensor wired in (and obviously its not hooked up currently). This means my o2 input looks like I'm constantly totally lean.
I'm tracking with you on the 'AFR Stoic. NB Ratio' setting effects and I played around with those values and saw a direct, proportional relationship to my PW after cranking. So since I'm not running an o2 sensor it appears I should set 'AFR Table Fuel Calc Usage' to 'Use Combined VE/AFR table'. I tried this and things seem to be running like they were on the v3.23 code. Does this sound right?
robh wrote:....So since I'm not running an o2 sensor it appears I should set 'AFR Table Fuel Calc Usage' to 'Use Combined VE/AFR table'. I tried this and things seem to be running like they were on the v3.23 code. Does this sound right?
Yes. In the combined mode there is no multiply by AFRStoich/AFRtarget so the problem goes away. In the AFR modes, the problem is not with the value of AFRStoich and AFRTarget, it is with the fact that the ratio was taken with different units on the top and bottom. It's like dividing inches/feet, you are always going to be off by a factor of 12 over and above the real ratio.
Also, if the ego is disconnected, then you should select the "Disabled" option under EGO Control to ensure you never go into ego control mode. If you want the ego values for datalogging, then make sure you set a condition such that Ego control never kicks in, for example 'active below map' = 10 kPa.
