Lowering VE doesn't change trims/low RPM lack of power due to extreme lean transition

[Exidous]

BLUF: I need to get my observed Min Inj PW lower. FIC lists it as 0.45ms but I can only get down to 1.7ms.

After I installed the FIC (clinic) 525cc injectors I've been having issues with hitting a Min Inj PW wall. About 1.7ms.

My issue is that when in the high vacuum areas of the VE/lower RPM range, IE 15,20&25kPa, I am not able to pull enough fuel out. The Min Inj PW will not drop below 1.7ms. This is causing my STFT to pull a lot of fuel in the neighborhood of 10-14%. At higher RPM this isn't an issue as the 1.7ms is fine. Around 2200RPM and below in OL the car goes VERY rich. The result of the STFT going negative is a get a huge dead spot in power on tip-in. The car goes VERY lean. >20 according to my WB.

Obviously going OL I do not have the STFT issues causing a loss of power on tip-in but that's a fix of the symptom and not the cause. I'd prefer to not run really rich at every tip-out. As a note, lowering Transient Fuel mg brought my Min Inj PW down to 1.7 from 2.2ms. Any further changes to TFmg only add instability to transient situations and doesn't lower MIpw.

Any help you can offer is appreciated.

Is there a better way to provide the scanner setup outside three separate files?

VE-WOT.Channels.Channels.xml
VE-WOT.Charts.xml
VE-WOT.Graphs.xml
5 oct 16 new inj-ve old spark RAF zero'd.hpt
dfco.hpl

[5FDP]

Does that log match the tune file you posted?

Because the tune file has all the fuel trims disabled but the log is showing them active. Also the MAF dtc's need to set to first error for speed density tuning.

[Exidous]

They all should be set to first error. I just changed that yesterday but it made no difference.

The log does match the tune. It was just the tune I used to do the RAF the afternoon before. All else is equal.

I don't know if the extreme lean is actually from not burning the fuel. I've had to add a lot of timing and 5 heat plugs just to keep the car from stumbling and smelling like fuel. The quench is quite tight. 93 Oct fuel.

Thanks for the response.

[Exidous]

Bump, I've updated my OP and title to reflect the current state of the issue I'm having. Thanks for looking!

Edit: From what I can tell the issue might be the combination of offset and inj pulse. If that's true, are the inj just too big?

I'm curious how folks handle off throttle high vacuum situations with high flow injectors. Do they use DFCO as a bandaid so the STFT's ignore those areas? Ex. 15,20&25kPa.

[Boosted53f]

see my post in a couple minutes for a possible fix for this.... at least for me.

this is most likely issue with min inj pulswidth and closed loop time out in decel map areas. will explain my situation in recent post

[Boosted53f]

The min PW wall you are referring to I commented about in the post I added. I am not the first one to have the issue or resolve it but the information about it is limited.

The min PW wall when you are in closed loop is driven by the Min Inj Pulse width and Default Inj Pulse... Not the min fuel mg the factory min inj pulse does not equate to 1.277 in the stock table. If you cut this in half the STFTs shouldnt freeze under dc and a locked PW. If you adjust these values and your seeing a LEAN decel... and your logs show your inj pw isnt freezing on decel then your VE is messed up in low map. Just make sure the min PW doesnt bottom out and lock the trims negative. check this in your logs. Negative locked trims will transition into lean tip in.

seems like this issue can be common for people running 38lb+ injectors