Reduced Engine Power...
Race Director
Joined: Nov 2012
Posts: 11,048
Likes: 3,390
If anything it will make you unable to turn off TC/AH.
I been running no TPMS in my cup wheels for about 2 months now, no reduced power.
Melting Slicks
Joined: Dec 2013
Posts: 2,232
Likes: 315
From: Bridgewater New Jersey
DTC P2101 Circuit Description The commanded throttle position is compared to the actual throttle position based on accelerator pedal position (APP) and possibly other limiting factors. Both values should be within a calibrated range of each other. The engine control module (ECM) continuously monitors the commanded and actual throttle positions. This DTC sets if the values are greater than the calibrated range.
Read more at: http://www.obd-codes.com/forums/viewtopic.php?t=3671
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Seems like a issue with the throttle command not working in sync with the TB. I wonder if you could operate the throttle while watching the TB blade operation to confirm it's in sync. It maybe not be opening all the way or shutting correctly or a non consistent opening of the blade
sticking or hanging up.
Obviously, do this with the engine off, ignition on.
The easy fix would be a bad connection at the TB; look for push back pins in the harness plugs and corrosion.
I think if you could drive around without testing the full throttle position and no codes get throne, you may have the answer there.
Your TPMS problems could be dead batteries in the sensors, being a older car, that could make sense, they don't last forever, ten years is what is normal.
Read more at: http://www.obd-codes.com/forums/viewtopic.php?t=3671
Copyright OBD-Codes.com
----------------------------------------------------------------------------------
Seems like a issue with the throttle command not working in sync with the TB. I wonder if you could operate the throttle while watching the TB blade operation to confirm it's in sync. It maybe not be opening all the way or shutting correctly or a non consistent opening of the blade
sticking or hanging up.
Obviously, do this with the engine off, ignition on.
The easy fix would be a bad connection at the TB; look for push back pins in the harness plugs and corrosion.
I think if you could drive around without testing the full throttle position and no codes get throne, you may have the answer there.
Your TPMS problems could be dead batteries in the sensors, being a older car, that could make sense, they don't last forever, ten years is what is normal.
Race Director
Joined: May 2004
Posts: 16,667
Likes: 1,209
From: Raleigh, NC
St. Jude Donor '15
If it consistently does it then they can log and see what's going on. They can record everything happening at the pedal and throttle body.
Is there a throttle relearn procedure? Seems like there is, though I've never done it and have had mine apart plenty of times
Is there a throttle relearn procedure? Seems like there is, though I've never done it and have had mine apart plenty of times
Last edited by schpenxel; Dec 28, 2015 at 11:50 PM.
Thread Starter
Racer
Joined: May 2010
Posts: 277
Likes: 4
From: MO
I think I can rule out air intake temps. I can recreate the event without running the car for more than a minute in 50 degree ambient temperatures.
I believe the car is setup for a 2-BAR MAF. You seem pretty confident its tune related. Has it occurred with you before? If the tune can be thrown off from unplugging the battery, something wasn't setup properly.
I can do the idle relearn but im not sure if that process is going to throw something else off.
I believe the car is setup for a 2-BAR MAF. You seem pretty confident its tune related. Has it occurred with you before? If the tune can be thrown off from unplugging the battery, something wasn't setup properly.
I can do the idle relearn but im not sure if that process is going to throw something else off.
Last edited by Spoolin8; Dec 29, 2015 at 10:16 AM.
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Race Director
Joined: May 2004
Posts: 16,667
Likes: 1,209
From: Raleigh, NC
St. Jude Donor '15
Maf isn't calibrated right doesn't make sense
Iat's being too high doesn't make sense
Throttle maps being changed on some can do some weird things so that one I could buy. I assume that's what you mean as there is no other "tuning" of the TB
But none of these ideas explain why it began popping up after the balancer install.
Do you have access to HP Tuners? I'll look up those codes when I get home tonight but seeing the tune and a log could help.
Iat's being too high doesn't make sense
Throttle maps being changed on some can do some weird things so that one I could buy. I assume that's what you mean as there is no other "tuning" of the TB
But none of these ideas explain why it began popping up after the balancer install.
Do you have access to HP Tuners? I'll look up those codes when I get home tonight but seeing the tune and a log could help.
Last edited by schpenxel; Dec 29, 2015 at 11:08 AM.
Thread Starter
Racer
Joined: May 2010
Posts: 277
Likes: 4
From: MO
After speaking with the tuner we are leaning towards a ground being off. Its possible the TB coincidentally is just now failing but im going to run through the harness with a fine tooth comb first.
It sounds like most the grounds for the throttle body are near the heads so im not sure how one may of been pulled but obviously Ill check it out. Thanks for the input. So many variables that it makes diagnosing it difficult.
It sounds like most the grounds for the throttle body are near the heads so im not sure how one may of been pulled but obviously Ill check it out. Thanks for the input. So many variables that it makes diagnosing it difficult.
Last edited by Spoolin8; Dec 29, 2015 at 12:47 PM.
Pro
Joined: Feb 2009
Posts: 598
Likes: 18
From: STL MO
I think I can rule out air intake temps. I can recreate the event without running the car for more than a minute in 50 degree ambient temperatures.
I believe the car is setup for a 2-BAR MAF. You seem pretty confident its tune related. Has it occurred with you before? If the tune can be thrown off from unplugging the battery, something wasn't setup properly.
I can do the idle relearn but im not sure if that process is going to throw something else off.
I believe the car is setup for a 2-BAR MAF. You seem pretty confident its tune related. Has it occurred with you before? If the tune can be thrown off from unplugging the battery, something wasn't setup properly.
I can do the idle relearn but im not sure if that process is going to throw something else off.
Read this thread
https://forum.efilive.com/showthread.php?10740-P1514-error-what-is-the-real-fix
I'm fighting this issue with a N/A LS7. When it's cold I don't have a problem but when I heat soak the engine I get the code when idling. They talk about this in a Greg banish book too. MAF is maxed out.
Last edited by BOTTLE FEDvette; Dec 29, 2015 at 03:56 PM.
Race Director
Joined: Oct 2010
Posts: 14,475
Likes: 783
From: Las Vegas NV
Race Director
Joined: May 2004
Posts: 16,667
Likes: 1,209
From: Raleigh, NC
St. Jude Donor '15
Was the new balancer the same size as the old?
You really need to get HPT/EFI live on it to see whats going on.
It is possible the MAF is maxed out.. but it makes no sense for a maxed out MAF to cause any issues at idle (to the other guy..)
I found this, though it is for 2006+'s, but still worth a read.
I would disable all of the airflow correlation DTC's just to see if it makes any difference.
You really need to get HPT/EFI live on it to see whats going on.
It is possible the MAF is maxed out.. but it makes no sense for a maxed out MAF to cause any issues at idle (to the other guy..)
I found this, though it is for 2006+'s, but still worth a read.
I would disable all of the airflow correlation DTC's just to see if it makes any difference.
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
Some customers may complain of a SES light. Upon inspection, oil in the air cleaner, a loose hydrocarbon patch in the air intake snorkel, and/or DTCs P0101, P0172, P0175, P1516, and/or P2176 may be found. This may be a result of an improper oil level or PCV restriction, which can cause excess oil to be forced into the engine air intake snorkel. If this occurs, the oil can contaminate the adhesive that attaches the hydrocarbon absorber to the air intake snorkel, causing the absorber to become mis-positioned, which can alter incoming air flow.
Recommendation/Instructions:
If this concern is encountered, complete the following steps and re-evaluate the concern:
Follow the owner's manual for proper engine oil filling procedures. For 7.0L LS7 models, also review the latest version of 05-06-01-032.
Perform the Crankcase Ventilation System Inspection/Diagnosis in SI to ensure that the PCV system is operating properly with no restrictions.
If equipped with an oil tank, ensure that the semi-fresh and fresh PCV tubes are installed correctly. The fresh PCV tube is attached to the front port of the oil tank, and the semi-fresh tube is attached to the rear port of the oil tank.
Clean excessive oil from the air intake system and inspect the hydrocarbon absorber in the air intake snorkel. Replace the air intake snorkel if the hydrocarbon absorber is mis-positioned or loose.
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
#PIP3089B: SES Light And Reduced Engine Power DTC P0120 P0220 P1516 P2135 - keywords accelerator actuator APP blade body connector connection DTC L33 L59 LH6 LR4 LM7 LS1 LS2 LQ4 LQ9 module position reduce sensor - (Oct 31, 2006)
Subject: SES Light and Reduced Engine Power DTC P0120 P0220 P1516 P2135
Models: 2004-2006 Buick Rainer
2005-2006 Cadillac CTS-V
2003-2006 Cadillac Escalade
2003-2006 Chevrolet Avalanche, Corvette, Express, Monte Carlo, Silverado, SSR, Suburban, Tahoe, Trailblazer
2003-2006 GMC Envoy, Savana, Sierra, Yukon
2003-2006 Hummer H2
2005-2006 Pontiac GTO
Equipped with a 4.8 5.3 6.0 or 7.0 V-8 Engine
--------------------------------------------------------------------------------
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
A vehicle may be brought into the dealer for a reduced power message, and DTCs P0120, P0220, P1516, P2101, or P2135.
The Throttle Actuator Control (TAC) / throttle body type trouble codes, may be caused by a loose wiring crimp at the throttle body connector, or a broken throttle body circuit.
Recommendation/Instructions:
Complete the current SI diagnostics for any symptoms or trouble codes found. If a intermittent T/P or TAC module type code is occurring complete the inspections below.
Inspect all related throttle body terminals for a loose wiring crimp. The loose crimp may be difficult to find, and the poor connection will be between the terminal and the copper strands of the wire. Wiggle test the individual throttle body circuits to see if the concern can be duplicated.
Inspect the related circuits for broken wires inside the insulation. The outer wire insulation may look fine, but the internal copper strands may be partially broken. Breaks in the wires usually occur within 1 to 4 inches of the throttle body connector. Wiggle testing may also induce a trouble code to set.
On C/K trucks complete SI procedures for voltage drop on grounds G103 and G104. Grounds G103 or G104 may be loose or corroded.
If a terminal crimp or a broken wire has been found, repair or replace only the circuits involved. There is a throttle body pigtail connector available through GMSPO, but installing this pigtail connector may cause other intermittent TAC module/TP codes at a later date. If this pigtail must be used, please follow the SI procedures for Splicing Copper Wire Using Splice Sleeves. (the proper Kent-Moore crimping tool must be used for this repair)
Condition/Concern:
Some customers may complain of a SES light. Upon inspection, oil in the air cleaner, a loose hydrocarbon patch in the air intake snorkel, and/or DTCs P0101, P0172, P0175, P1516, and/or P2176 may be found. This may be a result of an improper oil level or PCV restriction, which can cause excess oil to be forced into the engine air intake snorkel. If this occurs, the oil can contaminate the adhesive that attaches the hydrocarbon absorber to the air intake snorkel, causing the absorber to become mis-positioned, which can alter incoming air flow.
Recommendation/Instructions:
If this concern is encountered, complete the following steps and re-evaluate the concern:
Follow the owner's manual for proper engine oil filling procedures. For 7.0L LS7 models, also review the latest version of 05-06-01-032.
Perform the Crankcase Ventilation System Inspection/Diagnosis in SI to ensure that the PCV system is operating properly with no restrictions.
If equipped with an oil tank, ensure that the semi-fresh and fresh PCV tubes are installed correctly. The fresh PCV tube is attached to the front port of the oil tank, and the semi-fresh tube is attached to the rear port of the oil tank.
Clean excessive oil from the air intake system and inspect the hydrocarbon absorber in the air intake snorkel. Replace the air intake snorkel if the hydrocarbon absorber is mis-positioned or loose.
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
#PIP3089B: SES Light And Reduced Engine Power DTC P0120 P0220 P1516 P2135 - keywords accelerator actuator APP blade body connector connection DTC L33 L59 LH6 LR4 LM7 LS1 LS2 LQ4 LQ9 module position reduce sensor - (Oct 31, 2006)
Subject: SES Light and Reduced Engine Power DTC P0120 P0220 P1516 P2135
Models: 2004-2006 Buick Rainer
2005-2006 Cadillac CTS-V
2003-2006 Cadillac Escalade
2003-2006 Chevrolet Avalanche, Corvette, Express, Monte Carlo, Silverado, SSR, Suburban, Tahoe, Trailblazer
2003-2006 GMC Envoy, Savana, Sierra, Yukon
2003-2006 Hummer H2
2005-2006 Pontiac GTO
Equipped with a 4.8 5.3 6.0 or 7.0 V-8 Engine
--------------------------------------------------------------------------------
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
A vehicle may be brought into the dealer for a reduced power message, and DTCs P0120, P0220, P1516, P2101, or P2135.
The Throttle Actuator Control (TAC) / throttle body type trouble codes, may be caused by a loose wiring crimp at the throttle body connector, or a broken throttle body circuit.
Recommendation/Instructions:
Complete the current SI diagnostics for any symptoms or trouble codes found. If a intermittent T/P or TAC module type code is occurring complete the inspections below.
Inspect all related throttle body terminals for a loose wiring crimp. The loose crimp may be difficult to find, and the poor connection will be between the terminal and the copper strands of the wire. Wiggle test the individual throttle body circuits to see if the concern can be duplicated.
Inspect the related circuits for broken wires inside the insulation. The outer wire insulation may look fine, but the internal copper strands may be partially broken. Breaks in the wires usually occur within 1 to 4 inches of the throttle body connector. Wiggle testing may also induce a trouble code to set.
On C/K trucks complete SI procedures for voltage drop on grounds G103 and G104. Grounds G103 or G104 may be loose or corroded.
If a terminal crimp or a broken wire has been found, repair or replace only the circuits involved. There is a throttle body pigtail connector available through GMSPO, but installing this pigtail connector may cause other intermittent TAC module/TP codes at a later date. If this pigtail must be used, please follow the SI procedures for Splicing Copper Wire Using Splice Sleeves. (the proper Kent-Moore crimping tool must be used for this repair)
Pro
Joined: Feb 2009
Posts: 598
Likes: 18
From: STL MO
So you put a new pulley on your car right? Is it oversize? If so your making more power right? Was a retuned applied?
Computer (MAF) is seeing more air then it was used to and now going into limp mode to protect itself.
Computer (MAF) is seeing more air then it was used to and now going into limp mode to protect itself.
Race Director
Joined: Nov 2012
Posts: 11,048
Likes: 3,390
But all I'm saying is 0psi or no sensors giving an "xx" reading, the computer will not allow you to disable tc/ah.
Ether or on the tpms issue will not cut power.
Thread Starter
Racer
Joined: May 2010
Posts: 277
Likes: 4
From: MO
I replaced the stock harmonic balancer with the ATI equivalent. Kept the same belt, tune, etc.
The TPMS are still in the wheels but are giving me "0" as the psi read out. I have been able to turn off traction control even with this.
I dont think its a airflow related problem because I can turn the car on, have it idle perfect, Put it into 5th, nail the throttle and if I go to at least 90% it will go into reduced power. In 5th going 1mph, im at like 1,200rpms and I promise its not making any boost or moving much air at that point.
The TPMS are still in the wheels but are giving me "0" as the psi read out. I have been able to turn off traction control even with this.
I dont think its a airflow related problem because I can turn the car on, have it idle perfect, Put it into 5th, nail the throttle and if I go to at least 90% it will go into reduced power. In 5th going 1mph, im at like 1,200rpms and I promise its not making any boost or moving much air at that point.
Race Director
Joined: Oct 2010
Posts: 14,475
Likes: 783
From: Las Vegas NV
So you're saying I don't know what I'm talking about? Ok, good...carry on. I'm outa here.
Race Director
Joined: Nov 2012
Posts: 11,048
Likes: 3,390
I replaced the stock harmonic balancer with the ATI equivalent. Kept the same belt, tune, etc.
The TPMS are still in the wheels but are giving me "0" as the psi read out. I have been able to turn off traction control even with this.
I dont think its a airflow related problem because I can turn the car on, have it idle perfect, Put it into 5th, nail the throttle and if I go to at least 90% it will go into reduced power. In 5th going 1mph, im at like 1,200rpms and I promise its not making any boost or moving much air at that point.
The TPMS are still in the wheels but are giving me "0" as the psi read out. I have been able to turn off traction control even with this.
I dont think its a airflow related problem because I can turn the car on, have it idle perfect, Put it into 5th, nail the throttle and if I go to at least 90% it will go into reduced power. In 5th going 1mph, im at like 1,200rpms and I promise its not making any boost or moving much air at that point.
Race Director
Joined: Nov 2012
Posts: 11,048
Likes: 3,390
I was just saying it's not true you get reduced power with TPMS issues. Maybe with the electronic aids turned on, it will reduce power if it detects slippage. Which then i said someone who actually KNOWS about all that can comment. I'm not gonna spend hours trying to know every single detail of it.
But automatically reduced engine power the moment the computer finds out there's an issue with TPMS?? No that's not true.