Another good reason for getting the re-sized GM injectors from FIC.
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Another good reason for getting the re-sized GM injectors from FIC.
I called FIC today about my situation and they said to just tune the IFR table to match the previous injector behavior. I did continue the slope on the short pulse adder table. Going to flash and go drive soon.
I did three logs last night and the changes to the VE are shaping it more like a half pipe than a smooth hill. That definately cant be right. Im starting back to the VE tune prior to these injectors.
Did some more tuning last night. I created a histogram with the IFR table vs AFR err. Problem is now the table populates (from 0) around -5% to as high as 7% (around 40) and back to -5% rich (at 75). The paste X % half function turns the slope into a roller coaster. Id smooth it and log, did this a few times last night. I must be chasing another problem. Im guessing the high/low AFR errors in the VE table are skewing my IFR table. I think Im going to try to tune the VE and IFR by themsleves to less than +/-4%. Hopefully I can get "middle of the road" results.
Just curious did you purchase these injectors new or used?
Used, supposedly 6,000 miles on them.
I spent last night tuning again. If I tune just the VE, it turns into a half pipe. If I tune just the IFR, it turns into a roller coaster. :banghead:
It also drastically looks like DFCO below 3500 rpms in any cells coasting and engine braking. I have every table in dfco to max speed, 0 map, 0 throttle and it doesnt change anything. Still 20+ AFR in those cells. I flashed back to my original file and letting closed loop and fuel trims fix it until I can drop the car off with my tuner. I surrender.
Well I ran into bad luck. My tuner is overwhelmed with work and is declining any new business for the rest of the summer. On top of that, I had a valve spring break. Im lucky to not have any piston to valve contact. Hopefully back at fuel injector troubleshooting next week.
He does tuning on the side. I dont blame him for wanting to enjoy the summer too.
Im having a hell of a time with the SVO Green Tops as well...
http://www.hptuners.com/forum/showthread.php?t=30702
Whew, Im glad Im not the only one to ever run into this problem. I have a local tuning guru that offered me to look at my tune and help me out. I emailed him and am waiting for a reply back.
Meanwhile, Ive been getting tired of working on this car so Ive been cutting down the tuning time. Im running Greg's offset, short pulse, and min pulse tables with my previous VE and MAF tables. Ive been tuning only the IFR table. Above 30 kpa, its tuning out very well, less than 3% AFR error. 35 - 80 is still 35% - 40% lean. I keep trimming the IFR cells down and right now its nearly a straight line, no more slope and still lean.
Last night I copied my current IFR table into my closed loop tune and drove for about an hour. I made another histogram with the IFR vs STFT. (LTFT off)
-0.3 -5.8 -7.4 -7.9 -9.2 -8.9 -9.2 -8.4 -7.4 -6.8 -4.9 -5.2 -3.7 -5.7 -7.9 -10.0 -6.3
Its still correcting but not as much as the AFR error is in open loop. I keep thinking there has got to be something outside of the IFR table that is causing this. :banghead:
Well, your ahead of me and your on the Rich side... I only was rich when in an attempt to see rich, i put my PRE Injector tune in, then i was 20% rich. Now with the tables adjusted I just start the car and at idle and am 38% lean, let alone any other values along the IFR vac.
I am actually going to go back (rollback to my working tune)and ONLY change the IFR table and go from there, many on LS1tech say they dont adjust the other tables.
If it still shows large discrepancies, ill more than likely pull the injectors out and sell them as watching the DVD for the 11th is not in order.
Its odd that many say the xls from Calibrated Success works, and I truly thought it would, but I mean, my car only has a FAST intake and larger throttle which tuned in great prior, I followed the xls and boy oh boy, not even close.
Injectors themselves or those values are messed, or? what else is a factor, i even thought, maybe i cracked the FAST intake tightening the injectors down.. ill look at that too.
So I resorted to doing the math myself... and well, its still wrong, just leaving the injectors (they are used)... so I dont know.
I know how you feel, Im considering reselling these injectors too. Like Ive stated in my progress above, Ive tuned with stock tables and VE but its still lean with high vac. One more thing I want to do is measure each injector resistance cold and hot. Maybe I do have a bad injector(s) and its just not opening the pintle at low pulsewidths.
my green tops with gregs data worked awesome i switched to 60# seimens and entered gregs data and also worked awesome,the short pulse adder for the green tops should look like stairs and make shur your changing your offset vs volts vs kpa table.
i know my fuel pressure is 58 psi to so there is no correction needed for that being off or guessing if that is close.
Okay, as stated in a post in smithers thread (link above), I decided to put the stockers back in. Just got in from reflash and short idle log. Back to normal. Nice seeing less than -3% AFR error in the high vac IFR histo. Whenever I have an extra 100 bucks burning a hole in my pocket, I'll send the green tops out for rebuild. Giving up on nitrous again for another season. Oh well, runs great and going to the track on sunday! W00t!
Reviving this thread.....
I sent the injectors out to FIC last month, one was bad, now all cleaned and flowmatched. I also licensed and flashed an '02 OS tune. A couple days ago I put these injectors back in. Low and behold...SAME PROBLEMS!!!!
These injectors flowed 500cc @ 60psi. I calculated 47.xx @ 0 kPa Vac and 52.xx @ 80 vac, then interpolated to populate the IFR table. Copy/paste GB offset, short, and min tables. Same exact results as last year. Roughly 20% lean AFR in normal driving and max lean AFR on the wideband with engine decel, when scanning with CL and trims off.
I dont know what the hell to do from here. I've talked with a few local guys that self-tune and they've never heard of this problem either. Attached current tune file. Any input is appreciated.
What is your fuel pressure, it doesn't matter what FIC tested them at.
Stock, 58-60psi
Dont know what exactly, but its fixed. I put all the injector tables back to stock except IFR. Somehow I never noticed but the idle LTFT was still enabled. Tuning VE, its within 5% ish right off the bat....should have this tune done fairly soon. :cheers: