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My opinion (which might be completely wrong) is that your injectors are fine. I think you've got a pig rich decel which is carbon fouling your plugs.
Try replacing all your plugs with a fresh set and implement Darth V8r's suggestion of reducing your minimum pulse (including minimum transient pulse) and redo your MAF and VE.
Seems you are correct. New injectors balance my trims better but that's it.
I'm working on a new flash to try the ideas posted. So far I have confirmed injector data from the spreadsheet, reduced the injector timing in the upper temp to your recommended 5.9, and I am trying to follow the other suggestion but I have not clear on what table is meant by minimum transient pulse as I do not have a table called that. Do you know which that is in EFI live?
New plugs, new injectors, and put some different o2 sensors back in.
Tune changes: IAC effective area dropped 4 cells like you said, leaned out low rpm section of VE (going to try richer next), reduced warm injector timing.
This is killing me...first to admit I'm a pretty bad tuner but I had the car running nearly perfect. Gave my friend his injector back, installed new o rings on my injectors, fixed a small vaccum leak, changed the oil, and input "correct" injector data and this all started when I went to try to correct the VE and MAF data to match the new injector data.
I've unplugged the MAF to rule it out and I've loaded at least 2 dozen different VE maps which while they might not be fully correct everywhere I've been only really dicking with the idle areas and the car hasn't been leaving my garage between flashes of them.
I had 2 plugs fouled, one in each bank the passenger bank being much less fouled than the driver side which was pictured above.
Fuel pressure is rock solid when running. Been through a couple different fill ups so the fuel itself shouldn't be the problem.
It almost just has to be something simple I'm overlooking.
I googled to get the efi location for that parameter and my tune doesn't have it. Could be called something else but I don't see anything that is a single cell like that and I don't like to make assumptions and start messing with things I'm not sure of.
Once again I should stress I am really a novice here....I know mechanical stuff pretty well but I've been learning tuning as trial by fire and 90% of it is done using the efi live CALC.VET procedure to correct MAF and build a VE table and it's always worked well for me.
That said it auto builds the VE and I smooth it, but if it creates bad data in the decel range I'm not wise enough to know off hand and do anything with it. The data is averaged and filtered. It's never been an issue before but certainly could be now and I get that...I don't have many example tunes to compare my VE table to so that I know what's obvious wrong.
You didn't make me pull the MAF, I did it to rule it out and it takes all of 2 seconds since I just plug in my old stand alone IAT and leave the MAF unplugged. It's back on now that it's ruled out as a culprit.
Thought I was onto something with the idea of a weak coil. A local pro tuner said he has seen a weak one not fire at idle but work fine everywhere else. I hooked up my timing light and the cyl 3 had intermittent flash, but I changed the coil and plug wire for known good ones with the same result so maybe my timing light is crap or maybe the coil harness is damaged....it would have been off when I removed the valve cover to check hot lash on the rockers so it would make sense.
I did another smoke vacuum test with the engine warm just to be sure. Tomorrow I might plug the ports (notable the vacuum brake booster) just to rule it out for good.
The thing I keep coming back to in my mind is that the car was running...there is a video of it idling well in this thread. Then all of a sudden it wouldn't and nothing I do seems to help at all. So it's hard to think tables in the tune I've never touched are the culprit but I will continue to change them out of desperation.
Is there anything else mechanical I should be looking into in the mean time?
I have not clear on what table is meant by minimum transient pulse as I do not have a table called that. Do you know which that is in EFI live?
Minimum transient pulse is not available by default in EFILive. You have to download the {B9021} cax file which you can find by searching in the EFILive forums.
To speed things up, I've fixed up all your minimum fueling tables for you... including your minimum transient pulse.
Use this as a base tune... redo your MAF and VE as well as your rafig/rafpn. You may still have an idle surge after this, but it will be easier to fix when your fueling and airflow is in better shape.
I think its mostly a running rich or lean issue. I found with my car most surging root cause was wrong fueling, too rich usually IIRC. That doesn't really explain why when you were changing AFR it didn't really help tho...
Only thing I noticed in tune that might be an issue between idling good cold and idling bad warm is the "B3605 Commanded Fuel When in Open Loop". The stock tune starts off rich when cold and leans out to approx 1.00 Lambda at operating temp. The way its set up now is commanding same AFR cold and hot.
IMO it should look somthing like this. Starting point, reference only...
Minimum transient pulse is not available by default in EFILive. You have to download the {B9021} cax file which you can find by searching in the EFILive forums.
To speed things up, I've fixed up all your minimum fueling tables for you... including your minimum transient pulse.
Use this as a base tune... redo your MAF and VE as well as your rafig/rafpn. You may still have an idle surge after this, but it will be easier to fix when your fueling and airflow is in better shape.
Prior to that it would have been stock values I'm pretty sure.
Originally Posted by statesman
Check the resistance of your spark wires.
Will do. Right now I have 2 factory style ones on there and the rest are MSDs which are about 5-6 years old. I might order a new set as I'd been thinking about replacing them anyway to get the car fresh for race season.
Originally Posted by David_viny
I think its mostly a running rich or lean issue. I found with my car most surging root cause was wrong fueling, too rich usually IIRC. That doesn't really explain why when you were changing AFR it didn't really help tho...
Only thing I noticed in tune that might be an issue between idling good cold and idling bad warm is the "B3605 Commanded Fuel When in Open Loop". The stock tune starts off rich when cold and leans out to approx 1.00 Lambda at operating temp. The way its set up now is commanding same AFR cold and hot.
IMO it should look somthing like this. Starting point, reference only...
I will look into that as well. I might have accidentally messed it up when I was switching from a closed loop idle tune to an open loop idle tune?
One more thought. In HPTuners, this would be called "Derivative air". In EFILive, i think it is called "Filtered RPM Airflow Correction". There are two tables - low and high. The function is to look at the slope of the rpm change and predict a future value and pre-emptively adjust. At the lower end of the table, it can be trying to adjust for cam surge, starting an endless loop.
Stock values:
0.00....0.01....0.03.....0.04.....0.05.....0.06... ..0.07....0.09.......0.10 through the end
0.000..0.000...0.00....0.05x....1.00x...1.2x.....1 .5x.....1.75x......2.00000
New values:
0.00....0.01....0.03.....0.04.....0.05.....0.06... ..0.07...0.09 through the end
0.000..0.000...0.00....0.000....0.000...0.66.....1 .33.....2.00000
PS - I can't think of anything else mechanical in nature.
Just remembered I was putting off on plug wires until I get the roller rockers and taller valvecovers because I think I will need longer wires.
I'll test mine for now and if I find anything seriously wrong with them I'll just order the valvecovers and wires together and be ahead of the curve once I get the rockers.
Minimum transient pulse is not available by default in EFILive. You have to download the {B9021} cax file which you can find by searching in the EFILive forums.
Originally Posted by joecar
I can't see that on my phone... what is the name of it...?
Joe, he posted a picture of the HP Tuners screen showing "Minimum transient pulse" which is an item my EFI Live does not have apparently which explains why I couldn't find it by digging or searching for B9021 in my tune.
Lean out the VE table 2% at a time (entire thing) and set your OL fueling to 1 across the board. Your wideband might be off (it happens as they age and typically skew toward rich). 2% at a time would be safe enough.
01-24-2016, 01:31 PM
