Code 64 bank 2 o2 and bank1 LT fuel problem
#1
Code 64 bank 2 o2 and bank1 LT fuel problem
355 30lb injectors cam stage 3 dart pro heads etc
got a reflash from pcmforless for all new mods
started up great then cel came on code 64
im running heated o2 so I double checked wires and fuses (93 m6) replaced O2’s still the same
so I used scan9495 to see what’s going on
on start up o2 working fuel trims working.
then o2 bank 2 is .054 bank 1 is .800’s
bank 1 LT fuel trim is 108 and 2 is 160
fuel pressure is 43 I can feel injectors pulsing
checked for vacuum
exhaust is tight.
I did try starting it before tune and it was very rich but no cel
am I looking at a tune issue or am I missing something?
got a reflash from pcmforless for all new mods
started up great then cel came on code 64
im running heated o2 so I double checked wires and fuses (93 m6) replaced O2’s still the same
so I used scan9495 to see what’s going on
on start up o2 working fuel trims working.
then o2 bank 2 is .054 bank 1 is .800’s
bank 1 LT fuel trim is 108 and 2 is 160
fuel pressure is 43 I can feel injectors pulsing
checked for vacuum
exhaust is tight.
I did try starting it before tune and it was very rich but no cel
am I looking at a tune issue or am I missing something?
#2
Re: Code 64 bank 2 o2 and bank1 LT fuel problem
Are you sure you have the left and right bank O2 sensor signal wires connected to the correct ECM pins? Maybe “swapped”?
What do you mean by “on startup ..... fuel trims working “? Wasn’t it in open loop on startup?
If you post the .csv data log, I'll take a look at it.
What do you mean by “on startup ..... fuel trims working “? Wasn’t it in open loop on startup?
If you post the .csv data log, I'll take a look at it.
#3
Re: Code 64 bank 2 o2 and bank1 LT fuel problem
Are you sure you have the left and right bank O2 sensor signal wires connected to the correct ECM pins? Maybe “swapped”?
What do you mean by “on startup ..... fuel trims working “? Wasn’t it in open loop on startup?
If you post the .csv data log, I'll take a look at it.
What do you mean by “on startup ..... fuel trims working “? Wasn’t it in open loop on startup?
If you post the .csv data log, I'll take a look at it.
i did take a pic. But didn’t record yet. Cause I thought I had it handled. Guess not.
drives like crap tip in throttle is non existent it’s either yeehaa or nothing.
#4
Re: Code 64 bank 2 o2 and bank1 LT fuel problem
When you start it, it’s in open loop. It uses the stored long term trims (or 128 if PCM has been reset) and locks the short terms at 128. When it's in open loop ( 0 in “Eng. closed loop”) the fuel trims - meaning learning based on O2 sensor feed back - are not enabled ( 0 in “fuel trim enabled”). Even though it’s fully warmed up, and run time is over typical 206-second timer, apparently it’s not going into closed loop because of the problem with the O2 sensors. IAC counts are very high, struggling to maintain target idle RPM. Both fans are on at 181°F. How big is the cam? Stock or aftermarket throttle body?
When did pcmforless tune it? Since Bryan gave it up, results are not always what they used to be.
When did pcmforless tune it? Since Bryan gave it up, results are not always what they used to be.
#7
Re: Code 64 bank 2 o2 and bank1 LT fuel problem
Is this better?
but what’s the proper steps adjusting iac
one minute count is 70-90 then I adjust throttle stop and iac jumps to 160. Reset it car almost dies. Left it alone and now it’s 98
atleast banks are working and O2’s
#8
Re: Code 64 bank 2 o2 and bank1 LT fuel problem
Looking at a photo is relatively useless. Maybe pick out gross errors, but hard to pin down the cause. The ECM is updating as many as 10 times per second. That's why a log, with a scan rate of at least 5 frames per second is more useful. Knowing you have two O2 sensors that are no longer “stuck” is good, but is this going to correct the split/out-of-spec long term fuel trims (LTFT). Only watching how they respond, change, and hopefully stabilize over a period of time will show if there is still a problem, and perhaps suggest the cause.
Some aftermarket TB's contribute to high IAC counts, sometimes rectified by drilling an idle air hole in the TB.
Some aftermarket TB's contribute to high IAC counts, sometimes rectified by drilling an idle air hole in the TB.
#10
Re: Code 64 bank 2 o2 and bank1 LT fuel problem
Do I adjust throttle with iac unplugged
had to do brakes but did get to drive it
runs a whole lot better. Drivable but not clean on start and take off.
had to do brakes but did get to drive it
runs a whole lot better. Drivable but not clean on start and take off.
Last edited by grabbem88; 08-30-2020 at 09:40 PM. Reason: Forgot words
#11
Re: Code 64 bank 2 o2 and bank1 LT fuel problem
With IAC connected, TPS connected, slowly turn the stop screw to open the blades. As the blades open the IAC counts should drop to hold the target 900 RPM. You are trying to drop IAC into the range of 20-40 counts, and hold the idle at 900 RPM target. Problem is as you open the blades TPS volts will increase. You can't let them increase above about 0.85 volts.
You may not be able to get the RPM, IAC counts, and TPS volts into the correct range at the same time. As mentioned, some aftermarket throttle bodies don't pass enough air through the IAC passage, and they apparently don’t have a hole the stock TB has to flow additional idle air from between the bores directly into the intake plenum. Some people bore a hole and add a small tube, but I don’t know the details. I have a Holley 58mm TB and never had a problem. But I am using my stock PCM to control idle RPM (along with fan on/off temps, and speedometer), and everything else is controlled by an aftermarket engine management system that can accept any TPS volts for closed throttle.
You may not be able to get the RPM, IAC counts, and TPS volts into the correct range at the same time. As mentioned, some aftermarket throttle bodies don't pass enough air through the IAC passage, and they apparently don’t have a hole the stock TB has to flow additional idle air from between the bores directly into the intake plenum. Some people bore a hole and add a small tube, but I don’t know the details. I have a Holley 58mm TB and never had a problem. But I am using my stock PCM to control idle RPM (along with fan on/off temps, and speedometer), and everything else is controlled by an aftermarket engine management system that can accept any TPS volts for closed throttle.
#12
Re: Code 64 bank 2 o2 and bank1 LT fuel problem
Lol I shoulda left it all alone. Until I got back under car and found o2 issue.
thanks once again for your help. Knowledge of your stature is one of a kind
thanks once again for your help. Knowledge of your stature is one of a kind
#15
Re: Code 64 bank 2 o2 and bank1 LT fuel problem