Black2003SS Posted July 26, 2007 Report Share Posted July 26, 2007 (edited) I know B1 and B2 mean bank one and bank two...but what is the LT and ST stand for? What is that percentage measuring? I noticed that HPT had some default red light area that you dont want it to go into...well my bank 2 is different than B1...it went into the red today, like 25% or something on B2. Does that mean I'm lean or something? Edited July 26, 2007 by Black2003SS (see edit history) Quote Link to comment Share on other sites More sharing options...
misterp Posted July 26, 2007 Report Share Posted July 26, 2007 LT = "Long Term" fuel trim ST = "Short Term" fuel trim As the PCM sees feedback from the O2 sensors it will increment or decrement these values to compensate in it's fueling; ideally you want fuel trims to be zero, when they are not zero then the computer is seeing something happening it cannot explain - the O2's are reporting a rich or lean condition and the PCM does not know why. Negative numbers mean the PCM is subtracting fuel, and positive numbers means the PCM is adding fuel. Mr. P. Quote Link to comment Share on other sites More sharing options...
Black2003SS Posted July 26, 2007 Author Report Share Posted July 26, 2007 Ok, so it went positive 25%...on one bank...is that bad? it seems the B2 is having to compensate more than B1 under any load... Quote Link to comment Share on other sites More sharing options...
zippy Posted July 26, 2007 Report Share Posted July 26, 2007 I know B1 and B2 mean bank one and bank two...but what is the LT and ST stand for? What is that percentage measuring? I noticed that HPT had some default red light area that you dont want it to go into...well my bank 2 is different than B1...it went into the red today, like 25% or something on B2. Does that mean I'm lean or something? That means you are lean for sure. You did install the 42lb hr injectors with the Radix right? Quote Link to comment Share on other sites More sharing options...
Black2003SS Posted July 26, 2007 Author Report Share Posted July 26, 2007 (edited) yes..installed it like it came out of the box...injectors and all. I'm going to go downstairs and grab my laptop at lunch...try to email you the files and hopesully you can open them zippy. Edited July 26, 2007 by Black2003SS (see edit history) Quote Link to comment Share on other sites More sharing options...
Black2003SS Posted July 26, 2007 Author Report Share Posted July 26, 2007 Which side is Bank 2...drivers or passenger? Quote Link to comment Share on other sites More sharing options...
misterp Posted July 26, 2007 Report Share Posted July 26, 2007 Which side is Bank 2...drivers or passenger? B1 = Driver B2 = Passenger Quote Link to comment Share on other sites More sharing options...
Black2003SS Posted July 26, 2007 Author Report Share Posted July 26, 2007 I just looked at HPT and some old logs vs new. On average, LT B2 has always been higher than B1 even pre-blower. Now, I looked at the blower logs and as soon as I go WOT, the LT trims even out and match each other...usually around 3-6%. As soon as TPS goes to zero...B1 stays the same and B2 goes up to around 10%. What would cause this? One thing that has been in the back of my mind for a long time is the positioning of the cats. The way the exhaust guy did my cats, he put one right at the heade collector (the one on the passenger side) and the drivers side he put back behind the trans a few inches before the exhaust system flanges. Would that mess things up because the one has further to go than the other? I really need to get those cut out of there. Quote Link to comment Share on other sites More sharing options...
.justin. Posted July 26, 2007 Report Share Posted July 26, 2007 You'll never ever see fuel trims = 0 in the long term. It's just the nature of atmospheric changes, fuel composition, quality, etc. The closer to 0 you are, the better as there is less compensation having to occur. If you're seeing 6 on one bank and 10 on the other at low load and you recently installed the 42lb injectors along with the radix, I'd bank on that change being the culprit. Did you use the magnuson handheld to update your tune or do it yourself? If you did it yourself, did you alter the injector voltage offset table along with the flow rate table? Quote Link to comment Share on other sites More sharing options...
Black2003SS Posted July 26, 2007 Author Report Share Posted July 26, 2007 You'll never ever see fuel trims = 0 in the long term. It's just the nature of atmospheric changes, fuel composition, quality, etc. The closer to 0 you are, the better as there is less compensation having to occur. If you're seeing 6 on one bank and 10 on the other at low load and you recently installed the 42lb injectors along with the radix, I'd bank on that change being the culprit. Did you use the magnuson handheld to update your tune or do it yourself? If you did it yourself, did you alter the injector voltage offset table along with the flow rate table? Zippy did the tune for me. I know he changed those things...but one bank shouldnt be so far off the other...could be mechanical and thats what I am most worried about...tunes can be fixed, motors have to be rebuilt. Quote Link to comment Share on other sites More sharing options...
.justin. Posted July 26, 2007 Report Share Posted July 26, 2007 Zippy did the tune for me. I know he changed those things...but one bank shouldnt be so far off the other...could be mechanical and thats what I am most worried about...tunes can be fixed, motors have to be rebuilt. Does your radix have a front balance tube (line connecting the fuel rails at the front)? 4% variance between the two is nothing. When you get up to 8-10% variance or higher, then you should start to be concerned. Before I installed a front balance tube on my radix, I would see variance as high as 14% on decel. Quote Link to comment Share on other sites More sharing options...
Black2003SS Posted July 26, 2007 Author Report Share Posted July 26, 2007 No variance tube on the front... Maybe I'm just paranoid and I dont want anything to go wrong with my baby... The whistle issue needs to be tackled this weekend as well. Quote Link to comment Share on other sites More sharing options...
.justin. Posted July 26, 2007 Report Share Posted July 26, 2007 No variance tube on the front... Maybe I'm just paranoid and I dont want anything to go wrong with my baby... The whistle issue needs to be tackled this weekend as well. Okay, give magnuson a call and tell them you'd like the front balance tube and fittings for your radix. It's a flexible hose and should be $30-40. Helps to balance the fuel pressure between banks. Quote Link to comment Share on other sites More sharing options...
Black2003SS Posted July 26, 2007 Author Report Share Posted July 26, 2007 I'll get it from blownchevy on pt.net...magna pissed me off the last couple of times I called...it apepars they dont want to work with people on used kits or small parts. I called to order the TB gasket, updated intercooler, intercooler resevoir tank bracket (that goes on the fuse box) and they kept just transferring me around to people who all said it wasnt their job and I finally just hung up...blownchevy is sending me the bracket and TB gasket for free and getting me the intercoolr for a great price I think...cheaper than a fluidyne...and it bolts in. Quote Link to comment Share on other sites More sharing options...
.justin. Posted July 26, 2007 Report Share Posted July 26, 2007 I'll get it from blownchevy on pt.net...magna pissed me off the last couple of times I called...it apepars they dont want to work with people on used kits or small parts. I called to order the TB gasket, updated intercooler, intercooler resevoir tank bracket (that goes on the fuse box) and they kept just transferring me around to people who all said it wasnt their job and I finally just hung up...blownchevy is sending me the bracket and TB gasket for free and getting me the intercoolr for a great price I think...cheaper than a fluidyne...and it bolts in. That sucks. I've called magnuson at least 8 times for parts and they've been great to deal with every time. Quote Link to comment Share on other sites More sharing options...
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