Leaning out on quick TPS movements ... I need some advice.
10-05-2007, 03:22 AM
#1
Leaning out on quick TPS movements ... I need some advice. I have been noticing on my HPT Scanner that I get these sharp spikes of lean A/F readings from my LC-1 when I move the throttle in quick movements. I look at the average on my scanning and it show that there is not that big of a problem. But everytime I do it, I hear a pop and the motor stumbles. Right now, I have the close-loop and fuel trim turned off to do some fine tuning. I'll post my log file for those who want to look at it. BTW, it is a 3-bar SD tuning. I am afraid that went I shift gears at WOT and lifting my foot between shifts, I burn something up. It is almost like I need to step up the "accelerator pump" with more aggressive curve. Any ideas on what to try?
10-08-2007, 08:26 AM
#3
Post your tune and some details about your car. Your log looks like you shouldnt be running as rich as it is. But to answer your question, with it running that rich, it cant help but lean out when you crack the throttle. Its running a steady .750v. WB is 12:1 or so. Why so rich?
Last edited by edcmat-l1; 10-08-2007 at 10:18 AM.
10-08-2007, 07:41 PM
#4
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Since its 3 bar SD, I would assume its FI? Do you have an MSD booster for the fuel pump? What is fuel pressure doing when you step into it? More details are needed about the car and fuel system to make any determinations. I can't see the log cause I don't have HP tuners (I use EFILive).
10-09-2007, 08:58 PM
#5
Post your tune and some details about your car. Your log looks like you shouldnt be running as rich as it is. But to answer your question, with it running that rich, it cant help but lean out when you crack the throttle. Its running a steady .750v. WB is 12:1 or so. Why so rich?
And I'll attach my tune of what I had in that time.
10-09-2007, 10:37 PM
#6
Not really an answer, but here are some observations:
You are in closed loop, but have have active LT trims which are skewing your data. Reset your fuel trims. You are very lean moving to boost at moderate throttle..13.5:1-14.0:1. See frame 4356. You are commanding 11.42 across the board in your boost enrichment table. Set it to something fatter until you get this nailed down like 10.9-11.0. Log AFR % error and keep at the VE until AFR commanded comes in line with your wideband. Your HO spark map is very high... 25 degrees across the board at WOT from the 2krpms all the way up?! You have part-throttle AFRs at cruise in the 11s:1 dipping to the 10s. Be careful. Use the log, make the changes. Good luck.
You are in closed loop, but have have active LT trims which are skewing your data. Reset your fuel trims. You are very lean moving to boost at moderate throttle..13.5:1-14.0:1. See frame 4356. You are commanding 11.42 across the board in your boost enrichment table. Set it to something fatter until you get this nailed down like 10.9-11.0. Log AFR % error and keep at the VE until AFR commanded comes in line with your wideband. Your HO spark map is very high... 25 degrees across the board at WOT from the 2krpms all the way up?! You have part-throttle AFRs at cruise in the 11s:1 dipping to the 10s. Be careful. Use the log, make the changes. Good luck.