Lt b1- lt b2
Lt b1- lt b2 I am trying to get my car tuned. I have hp tuners. Its a head and cam car. I had it starting and idleing without giving it gas. That only lasted for a day. Now it won't idle or start without giving it gas. I have to hold my gas pedal to make it idle. I noticed on my scanner that the ltb1 and ltb2 are at 25%. How do I correct this?
You need more fuel. +25% means your O2's are pegged and trying to add as much fuel as possible to bring things back into line.
One of your parameters in the tune may be off.
What size cam?
One of your parameters in the tune may be off.
What size cam?
Try kicking the thing to open loop. That cam has a lot of overlap.
Put in max values for the closed loop enable table and do a write-full to clear out the old LTerms.
If it works, you can either leave the car like that or get fancy with the tune have have it OL for idle but CL everywhere else.
Put in max values for the closed loop enable table and do a write-full to clear out the old LTerms.
If it works, you can either leave the car like that or get fancy with the tune have have it OL for idle but CL everywhere else.
I put in max values for closed loop and entire write. That did help my lt. My wideband is still showing high 15 and 16.0 most of the time. This is a new wideband and I did calibrate it before I used it. Running that lean is worrying me. I also noticed that my 02 sensors are showing a big differance in readings and one is jumping from 100s to 500s a lot while the other is staying around 100s.
Last edited by zeekracing; May 1, 2009 at 03:27 PM. Reason: more info
Your LT should be zero now....they are not being referenced in open loop.
BIG cams cause O2 problems. They don't move much air through the motor at lower rpms and overlap can inflate O2 readings.
Your PE table will only be in effect at the lower rpm if you change the TPS enable table (hot and cold) for the lower rpm to 0, and in some cars the overall RPM and MAP enable. This puts your car on the PE table with the throttle closed. Otherwise, you have to meet the standard WOT conditions before this table is referenced for fueling.....maybe you already know this.
While in open loop you are on the Open Loop Commanded A/F table....I forget what it is called in HP tuners. Its under the fueling section though. A quick and dirty way to richen up your idle is to use this table and increase the value for idle conditions.
With all this being said though, the 100% correct way to do it once you've reached this point is to adjust the VE table. But that depends on how proficient and how much time you have.
BIG cams cause O2 problems. They don't move much air through the motor at lower rpms and overlap can inflate O2 readings.
Your PE table will only be in effect at the lower rpm if you change the TPS enable table (hot and cold) for the lower rpm to 0, and in some cars the overall RPM and MAP enable. This puts your car on the PE table with the throttle closed. Otherwise, you have to meet the standard WOT conditions before this table is referenced for fueling.....maybe you already know this.
While in open loop you are on the Open Loop Commanded A/F table....I forget what it is called in HP tuners. Its under the fueling section though. A quick and dirty way to richen up your idle is to use this table and increase the value for idle conditions.
With all this being said though, the 100% correct way to do it once you've reached this point is to adjust the VE table. But that depends on how proficient and how much time you have.
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Verdad Gallardo I tried adding to the eq ratio in open loop and could get the afr in the safe range but I could not get it to idle correctly. It would try to die and then rev way high. I tried with the pe table and it would just keep the rpms high when I added fuel to it. I guess I need to try raising the numbers on the primary ve table?
i've been doing a lot of research trying to figure this out. I ended up finding a post on hp tuners forum. It descibes on how big cames will give a false afr reading becuase of the valve over lap. That would explain why when I added more fuel to it the rpms would not come back down, I guess. I got it idling smooth. Then took it for a test drive and my afr was 12.4 a little rich. I ended up with a broken trans mount. I hope everything is ok.
