For anyone who forced the computer into open loop at idle
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From: Cecil County Raceway!!!
For anyone who forced the computer into open loop at idle I set my car to be at WOT tuning for 0-1200 rpm at 0% TPS to force the car into open loop. My "little" cam and the slip on collectors on the dynatechs are causing a severe rich condition at idle if in closed loop (don't start until car is up to operating temp)
I was wondering what kind of values in the PE-RPM table people are using for 0-1200 idle fueling. I just put mine at -1.000 and it still is acting a bit rich <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />
I was wondering what kind of values in the PE-RPM table people are using for 0-1200 idle fueling. I just put mine at -1.000 and it still is acting a bit rich <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />
Re: For anyone who forced the computer into open loop at idle Did you try just leaving the car in Open loop until it is warmed up and changing the fuel air multiplier table? (or are you saying the problem occurs in closed loop only when the car is fully warmed up)
You could skew the low end MAF rates to lean it out too. let the car idle all the way from cold to hot and log your MAF rates. Then reduce your MAF rates 3 - 5% at those frequencies. I would start a few frequencies above so that you can make a smooth curve starting with a 1% adjustment. That should lean it out for you.
You could skew the low end MAF rates to lean it out too. let the car idle all the way from cold to hot and log your MAF rates. Then reduce your MAF rates 3 - 5% at those frequencies. I would start a few frequencies above so that you can make a smooth curve starting with a 1% adjustment. That should lean it out for you.
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From: Cecil County Raceway!!!
Re: For anyone who forced the computer into open loop at idle the maf may not work as the fueling at idle is skewed by the leaky collectors misreading the o2 content. I figured since WOT won't occur below 1200 rpm I could force it into PE/RPM and adjust from there...is there a flaw in this idea?
my problem before existed once it acheived closed-loop at idle. it couldn't maintain proper fueling even though it seems ok at part throttle cruising. so I wanted to send it into open loop at idle to force it to lean out without relying on the O2 sensors
<small>[ September 19, 2002, 09:33 AM: Message edited by: Fireball ]</small>
my problem before existed once it acheived closed-loop at idle. it couldn't maintain proper fueling even though it seems ok at part throttle cruising. so I wanted to send it into open loop at idle to force it to lean out without relying on the O2 sensors
<small>[ September 19, 2002, 09:33 AM: Message edited by: Fireball ]</small>
Re: For anyone who forced the computer into open loop at idle The leaky collectors will continue to skew the results, but you would be starting from a leaner condition if adjust the MAF table.
What happens if you raise your idle another 50 - 100 rpm? (I realize that could cost you the lope. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> )
Does WOT trump the Fuel Air Multiplier table or do they work together? You could try adjusting the low load column to see if that leans you out. How many Kpa's do you see at idle?
Why not fix the leaky collectors? <img border="0" title="" alt="[Razz]" src="gr_tounge.gif" />
What happens if you raise your idle another 50 - 100 rpm? (I realize that could cost you the lope. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> )
Does WOT trump the Fuel Air Multiplier table or do they work together? You could try adjusting the low load column to see if that leans you out. How many Kpa's do you see at idle?
Why not fix the leaky collectors? <img border="0" title="" alt="[Razz]" src="gr_tounge.gif" />
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From: Cecil County Raceway!!!
Re: For anyone who forced the computer into open loop at idle </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Ragtop 99:
<strong>
Why not fix the leaky collectors? <img border="0" title="" alt="[Razz]" src="gr_tounge.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I will but I need to find a time when the lift isn't occupied, I'm not occupied and Tyson isn't occupied....thats alot to ask for nowadays <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
<strong>
Why not fix the leaky collectors? <img border="0" title="" alt="[Razz]" src="gr_tounge.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I will but I need to find a time when the lift isn't occupied, I'm not occupied and Tyson isn't occupied....thats alot to ask for nowadays <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
Re: For anyone who forced the computer into open loop at idle Fireball,
I have forced the computer into open loop at all times (by changing the closed loop enable temp to a pretty high value).
Part throttle tuning is much more of a pain in the *** in open loop...but WOT tuning is a lot easier because there are really no LTRIM values to worry about the computer adding or subtracting fuel.
I am in the process of trying to figure out how to get the part throttle/idle tuning under control and then I am going to ditch the o2 sensors completely (I have a WB o2 system in the car though, so I can see what it is doing at all RPM/throttle conditions).
I'll keep the board posted on how the tuning goes.
Scott
I have forced the computer into open loop at all times (by changing the closed loop enable temp to a pretty high value).
Part throttle tuning is much more of a pain in the *** in open loop...but WOT tuning is a lot easier because there are really no LTRIM values to worry about the computer adding or subtracting fuel.
I am in the process of trying to figure out how to get the part throttle/idle tuning under control and then I am going to ditch the o2 sensors completely (I have a WB o2 system in the car though, so I can see what it is doing at all RPM/throttle conditions).
I'll keep the board posted on how the tuning goes.
Scott
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From: Melbourne, FL
Re: For anyone who forced the computer into open loop at idle </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Scott 98Z M6:
<strong>I am in the process of trying to figure out how to get the part throttle/idle tuning under control and then I am going to ditch the o2 sensors completely (I have a WB o2 system in the car though, so I can see what it is doing at all RPM/throttle conditions).
I'll keep the board posted on how the tuning goes.
Scott</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I'll be keeping my eyes peeled, as I really haven't done much in the way of part throttle tuning on my open-loop setup.
I still think I'm a little lean at idle and part throttle.
The WOT stuff is cake, though <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
<strong>I am in the process of trying to figure out how to get the part throttle/idle tuning under control and then I am going to ditch the o2 sensors completely (I have a WB o2 system in the car though, so I can see what it is doing at all RPM/throttle conditions).
I'll keep the board posted on how the tuning goes.
Scott</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I'll be keeping my eyes peeled, as I really haven't done much in the way of part throttle tuning on my open-loop setup.
I still think I'm a little lean at idle and part throttle.
The WOT stuff is cake, though <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
