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fired up my turbo 5.3 a few days ago. im having trouble tuning the thing. Idle seems to be rough. when I give it a bit of throttle in park the rpm drops and it wants to die then smooth out, give it throttle while in gear, it dies... Any advice or feedback is greatly appreciated.
rundown on my setup
5.3
216/220 112 lsa cam
SEP 80lb injectors
76/75 turbo
2 Bar map
80e 3200 stall
Thanks in Advance!
Cut the over/underspeed spark correction tables down to +/- 8 degrees, right now it can swing the timing way too much. Play around with idle timing as well, it might want 18 degrees instead of 22.
Did those injectors come with all the data you need like flow rate, short pulse adder, min injector pulse and offset settings??
I don't see o2 sensor data, injector pulse width or a wideband in the logs to see how the fueling is doing. If the airflow model is really off or it's idling overly lean/rich, you will have a hell of a time getting the timing and base running airflow squared away.
Yes i have the data for the injectors. i couldnt get it to fire with the correct data. forgive me im a bit green to tuning and vcm scanner. i have a wideband, not sure on how to add it to vcm yet.. wideband gauge reading from around 10-13 in park. any amount of throttle makes it go rich ,let off throttle it goes lean then evens back out..
Why wouldn't it work with the correct data?
Can you post that data here?
Are they 80's at 43.5 or 58psi and what pressure do you have your regulator set at?
80's at 43.5psi, have not installed an adjustable regulator yet, im running the factory rails and regulator. when i used the data they sent it would turn over and not start.
Factory fuel pressure is more around 58psi on these, so you will need to adjust the flow rate data for that.
The spreadsheet looks like it already has the g/sec at 58psi, so that is just a copy paste. Then the min injector pulse and offsets looks right. Just the short pulse adder isn't right and the short pulse limit needs to be changed to 2.000.
ok, i'll give it a shot tomorrow and let you know how it goes.
thanks again.
alright so after messing with the tune i posted the other day, i screwed something up to the point where idle was no good and it would die when shifted. so i decided to start all over and give it another shot with some luck this time. idle seems ok now,(then again im not entirely sure what else it needs). I did use the injector data that SEP sent me, it worked. I was able to get it in reverse and drive with out it sputtering and drive it around the block but the issue now is i was not able to go above 1000-1500 rpm, every time i gave it some throttle, it would sputter and fall on its face. at one point i was at 70% tps and choking around 1200rpm and wideband gauge reading so lean that it wont display a value, let off the throttle a bit and let it coast AFR sits around 14-15.
after doing some research, i think my tune is running closed loop. would it benefit to run open loop? correct me if I'm wrong, closed loop uses LTFT and STFT to correct fuel?
and open loop purely uses VE table?
The -/+ 8 on the over/under speed seemed to have helped!
I posted the new tune and log file for reference.
Thanks again. I really appreciate the advice!
SCRATCH THAT. disregard last post. i worked on it some more. it idles good, doesnt die when shifted, im able to drive it. getting on the throttle it seems like its falling on its face a bit. in boost @ high rpm (4k+) it falls on its face hard and backfires.
I'm not looking for anyone to work on my tune, just advice on what to look at and why.
I've posted my updated tune and log
Thanks!
Getting into boost should be the last thing you do. You must get your wideband data into your logs somehow. Either with the PRO interface or logging the wideband through a 5v reference circuit like the AC pressure sensor or the EGR. You need to tune this in open loop with no fuel trims using a wideband error to log the error between the commanded AFR and the actual AFR the sensor is seeing.
Your still missing your o2 sensor data, knock retard and injector data in the logs, those are really helpful in seeing how things are doing. Also the 1 bar map sensor channel needs to be removed and replaced with the 2 bar MAP channel so kpa over 105 can be logged.
Thanks for the reply. i have not tapped into a 5v source for my wideband yet, will do that ASAP. i reconfigured my scanner for the russ k files in order to see idle air flow. need to rearrange it a bit better in there. in that last tune i believe it was running open loop with LTFT disabled.
also does not help that i found 3 of the 4 plug wires near the hotside had burned. with heat sleeves. so ill be looking for a solution there but i will def make those changes and start logging with the AEM wideband.
thanks again for the help.