Going nuts.....another in-depth tuner question..$50 Paypal whoever figures it out.
#1
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Maybe you saw my other thread...
https://ls1tech.com/forums/pcm-diagn...-****-out.html
Basically I still have the codes below....with two brand new 02 sensors.
I checked everything regarding wires, plugs, PCM pin rows, ground wires...and both front 02 sensors are new. New coolant temp sensor.
Question:
Can one "bad" new 02 sensor cause the other 02 sensor to read problems and throw its own codes?
I still have these codes......and still, this problem ONLY misses/stumbles about 1 minute after start-up, it does it for about 10-30 seconds, and then it clears up for the rest of the day and the engine runs perfect until it cools down and I start it again to drive it.
Or is there something that can throw all these EQUAL codes on both sides at one time.
P0131 0P2 Sensor Circuit Low Voltage (Bank I Sensor I)
P0133 02 Sensor Circuit Slow Response (Bank 1 Sensor 1)
P0151 02 Sensor Circuit Low Voltage (Bank 2 Sensor I)
P0153 02 Sensor Circuit Slow Response (Bank 2 Sensor 1)
P0171 System too Lean (Bank 1)
P0174 System too Lean (Bank 2)
Heading to a dealership where a friend works, he's gonna take a crack at it today. If he doesn't find it, the $50 is still in play................
.
https://ls1tech.com/forums/pcm-diagn...-****-out.html
Basically I still have the codes below....with two brand new 02 sensors.
I checked everything regarding wires, plugs, PCM pin rows, ground wires...and both front 02 sensors are new. New coolant temp sensor.
Question:
Can one "bad" new 02 sensor cause the other 02 sensor to read problems and throw its own codes?
I still have these codes......and still, this problem ONLY misses/stumbles about 1 minute after start-up, it does it for about 10-30 seconds, and then it clears up for the rest of the day and the engine runs perfect until it cools down and I start it again to drive it.
Or is there something that can throw all these EQUAL codes on both sides at one time.
P0131 0P2 Sensor Circuit Low Voltage (Bank I Sensor I)
P0133 02 Sensor Circuit Slow Response (Bank 1 Sensor 1)
P0151 02 Sensor Circuit Low Voltage (Bank 2 Sensor I)
P0153 02 Sensor Circuit Slow Response (Bank 2 Sensor 1)
P0171 System too Lean (Bank 1)
P0174 System too Lean (Bank 2)
Heading to a dealership where a friend works, he's gonna take a crack at it today. If he doesn't find it, the $50 is still in play................
.
Last edited by LS6427; 10-07-2011 at 04:44 PM.
#2
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BUMP....and an update.
I just drove home from the gym....this time after I pulled away, about 1 minute into driving, the missing/stumbling started and lasted just about 5 seconds one time....then never returned all the way home. Usually it stays for about 30 seconds, sometime it comes and goes in 5 second intervals for 30 seconds and then stops.
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I just drove home from the gym....this time after I pulled away, about 1 minute into driving, the missing/stumbling started and lasted just about 5 seconds one time....then never returned all the way home. Usually it stays for about 30 seconds, sometime it comes and goes in 5 second intervals for 30 seconds and then stops.
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#3
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If both bank set lean codes it is generally something that affects both banks. The lean codes don't set until the pcm is commanding an extra 25% fuel to compensate for the problem. There has been no talk of fuel pressure and volume testing so that is a first step and will take less than 5 min to rule out. If that is good then I would look at the MAF failing in range hence no code.
#4
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If both bank set lean codes it is generally something that affects both banks. The lean codes don't set until the pcm is commanding an extra 25% fuel to compensate for the problem. There has been no talk of fuel pressure and volume testing so that is a first step and will take less than 5 min to rule out. If that is good then I would look at the MAF failing in range hence no code.
....could I go buy a stock MAF and try it to see if it fixes the issue....with the tune I have in it for my 427ci?
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#5
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I think 2 possible things:
1- Your O2's are too far from exhaust collector and they are working too cold.
2- You need to tune VE and MAF with a wideband, because the AFR is too lean when engine is in open loop, when it goes closed loop it compensates a little and works better, but it's far from ideal.
1- Your O2's are too far from exhaust collector and they are working too cold.
2- You need to tune VE and MAF with a wideband, because the AFR is too lean when engine is in open loop, when it goes closed loop it compensates a little and works better, but it's far from ideal.
#7
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2- You need to tune VE and MAF with a wideband, because the AFR is too lean when engine is in open loop, when it goes closed loop it compensates a little and works better, but it's far from ideal.
The car sat for 4 months waiting for a new tranny, when I got it installed I started it up and both 02 sensors (maybe 5 years old each) were showing switching problems. I went and got two new 02 sensors and it was great for 3 months. Then all of sudden...this starts and those codes.
Could I go get a stock MAF from Advance Auto to try....will it work on my 427ci tune? Just as a weeding out process to see if my MAF is dying.
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#8
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Ok...even with no MAF code.....it can cause this stuff, right?
Its a 10 year old Z06 MAF...it went on when they installed my 427ci. back in 2002.
edit: I see Advance Auto has them (2002 Z06 MAFs) for $85.00. Could I go get one to try....will it work on my 427ci tune? Just as a weeding out process to see if my MAF is dying.
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Its a 10 year old Z06 MAF...it went on when they installed my 427ci. back in 2002.
edit: I see Advance Auto has them (2002 Z06 MAFs) for $85.00. Could I go get one to try....will it work on my 427ci tune? Just as a weeding out process to see if my MAF is dying.
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Last edited by LS6427; 10-07-2011 at 10:37 PM.
#9
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Sounds like lean open loop, wether it be tuning or unmetered air entering somewhere. It could be q maf issue. Needs to be logged to see error difference between commanded and actual fueling.
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have you checked for exhaust leaks upstream from and close to the O2 sensors?
if air from the outside environment gets into the exhaust and the O2s pick it up, it will intepret a lean condition and throw fuel in like crazy. This won't happen in open loop while the car is warming up, only when it starts using the O2s in closed loop as part of the fueling calculations.
did you by any chance get oil/grease/anit-seize/coolant/etc...on the O2 sensors before installing them? they could be fouled by some other kind of contamination....could also maybe be a leaking exhaust valve seal, getting oil in the exhaust and fouling the sensors....its a long shot, but i'm just trying to think outside the box here
if air from the outside environment gets into the exhaust and the O2s pick it up, it will intepret a lean condition and throw fuel in like crazy. This won't happen in open loop while the car is warming up, only when it starts using the O2s in closed loop as part of the fueling calculations.
did you by any chance get oil/grease/anit-seize/coolant/etc...on the O2 sensors before installing them? they could be fouled by some other kind of contamination....could also maybe be a leaking exhaust valve seal, getting oil in the exhaust and fouling the sensors....its a long shot, but i'm just trying to think outside the box here
#15
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have you checked for exhaust leaks upstream from and close to the O2 sensors?
if air from the outside environment gets into the exhaust and the O2s pick it up, it will intepret a lean condition and throw fuel in like crazy. This won't happen in open loop while the car is warming up, only when it starts using the O2s in closed loop as part of the fueling calculations.
if air from the outside environment gets into the exhaust and the O2s pick it up, it will intepret a lean condition and throw fuel in like crazy. This won't happen in open loop while the car is warming up, only when it starts using the O2s in closed loop as part of the fueling calculations.
did you by any chance get oil/grease/anit-seize/coolant/etc...on the O2 sensors before installing them? they could be fouled by some other kind of contamination....could also maybe be a leaking exhaust valve seal, getting oil in the exhaust and fouling the sensors....its a long shot, but i'm just trying to think outside the box here
Leaking valve.......again though, the problem would always be present all day, right?
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#18
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I had a guy scan it with HP Tuners and he could see out of the ordinary was the 02 sensors not switching properly. Right side sensor was only reading between 0-4....left one was up in the 400-800 range, but he said they were switching slowly.
I'll get new 2002 Z06 MAF tomorrow and see if that fixes it, they're around $55.00 at Advance Auto with a 40% off coupon code I found on the net. "BIG35"
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I'll get new 2002 Z06 MAF tomorrow and see if that fixes it, they're around $55.00 at Advance Auto with a 40% off coupon code I found on the net. "BIG35"
.
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But wouldn't a leak always cause stumbling/missing from the richness.......this clears up after 20-30 seconds and its great the rest of the day.
I didn't use anything on the 02 sensor threads this time.
Leaking valve.......again though, the problem would always be present all day, right?
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I didn't use anything on the 02 sensor threads this time.
Leaking valve.......again though, the problem would always be present all day, right?
.