Eng pwr reduced - FML (please help)
09-20-2009, 03:31 PM
#1
Senior Member
Thread Starter
iTrader: (2)
Join Date: 07-07-05
Location: Houston, TX
Posts: 799
Likes: 0
Received 0 Likes
on
0 Posts
Eng pwr reduced - FML (please help)
I had a big problem with my 2005 Cobalt SS/SC yesterday. I'm so pissed off.
It went into ENGINE POWER REDUCED mode and has a mess of 'check engine light' codes, in a situation where this absolutely shouldn't have happened. My engine is COMPLETELY STOCK except for an intake, and I only have 55,993 miles on the clock as it sits.
Here's a video of what happened:
http://www.youtube.com/watch?v=J1mQ7t4hfD4
I was doing a burnout. We'd splashed water under the tires. I pulled the handbrake all the way up. I rev it up, maybe to 4,000 or 5,000, drop the clutch, and give it some throttle. It lasted about a second. The car went a few feet, and the burnout just stopped. Obviously because power had been reduced.
We used a DiabloSport to scan the codes. It had 'system too lean' and 'MAF', which pop up a lot because of my aftermarket intake. But then it also had something like 'clutch switch'.
We took out the clutch switch, tested it, saw it was working fine, put it back. So we tried clearing the codes. Then the car wouldn't start AT ALL. Around this point I was pondering calling AAA.
Pulled the PCM fuse and put it back in. Now the car started- and with full power. But it still had the 'check engine light', so we scanned it again, and it had WAY MORE CODES. Maybe five or six of them. 'System too lean', 'MAF', I think 'Clutch switch', and two relating to the throttle, perhaps 'throttle position' and 'throttle (something else)'.
The car SEEMS to be driving fine and with full power, but I still have a 'check engine light' with all the error codes.
It would appear as if there is nothing mechanically wrong, but my engine's computer flipped out and is confused.
WHY would this happen, and how can I remedy it?
PLEASE offer some theories, advice, and solutions.
It went into ENGINE POWER REDUCED mode and has a mess of 'check engine light' codes, in a situation where this absolutely shouldn't have happened. My engine is COMPLETELY STOCK except for an intake, and I only have 55,993 miles on the clock as it sits.
Here's a video of what happened:
http://www.youtube.com/watch?v=J1mQ7t4hfD4
I was doing a burnout. We'd splashed water under the tires. I pulled the handbrake all the way up. I rev it up, maybe to 4,000 or 5,000, drop the clutch, and give it some throttle. It lasted about a second. The car went a few feet, and the burnout just stopped. Obviously because power had been reduced.
We used a DiabloSport to scan the codes. It had 'system too lean' and 'MAF', which pop up a lot because of my aftermarket intake. But then it also had something like 'clutch switch'.
We took out the clutch switch, tested it, saw it was working fine, put it back. So we tried clearing the codes. Then the car wouldn't start AT ALL. Around this point I was pondering calling AAA.
Pulled the PCM fuse and put it back in. Now the car started- and with full power. But it still had the 'check engine light', so we scanned it again, and it had WAY MORE CODES. Maybe five or six of them. 'System too lean', 'MAF', I think 'Clutch switch', and two relating to the throttle, perhaps 'throttle position' and 'throttle (something else)'.
The car SEEMS to be driving fine and with full power, but I still have a 'check engine light' with all the error codes.
It would appear as if there is nothing mechanically wrong, but my engine's computer flipped out and is confused.
WHY would this happen, and how can I remedy it?
PLEASE offer some theories, advice, and solutions.
09-20-2009, 03:41 PM
#2
Senior Member
Join Date: 05-17-09
Location: Minnesota
Posts: 719
Likes: 0
Received 0 Likes
on
0 Posts
I had a big problem with my 2005 Cobalt SS/SC yesterday. I'm so pissed off.
It went into ENGINE POWER REDUCED mode and has a mess of 'check engine light' codes, in a situation where this absolutely shouldn't have happened. My engine is COMPLETELY STOCK except for an intake, and I only have 55,993 miles on the clock as it sits.
Here's a video of what happened:
http://www.youtube.com/watch?v=J1mQ7t4hfD4
I was doing a burnout. We'd splashed water under the tires. I pulled the handbrake all the way up. I rev it up, maybe to 4,000 or 5,000, drop the clutch, and give it some throttle. It lasted about a second. The car went a few feet, and the burnout just stopped. Obviously because power had been reduced.
We used a DiabloSport to scan the codes. It had 'system too lean' and 'MAF', which pop up a lot because of my aftermarket intake. But then it also had something like 'clutch switch'.
We took out the clutch switch, tested it, saw it was working fine, put it back. So we tried clearing the codes. Then the car wouldn't start AT ALL. Around this point I was pondering calling AAA.
Pulled the PCM fuse and put it back in. Now the car started- and with full power. But it still had the 'check engine light', so we scanned it again, and it had WAY MORE CODES. Maybe five or six of them. 'System too lean', 'MAF', I think 'Clutch switch', and two relating to the throttle, perhaps 'throttle position' and 'throttle (something else)'.
The car SEEMS to be driving fine and with full power, but I still have a 'check engine light' with all the error codes.
It would appear as if there is nothing mechanically wrong, but my engine's computer flipped out and is confused.
WHY would this happen, and how can I remedy it?
PLEASE offer some theories, advice, and solutions.
It went into ENGINE POWER REDUCED mode and has a mess of 'check engine light' codes, in a situation where this absolutely shouldn't have happened. My engine is COMPLETELY STOCK except for an intake, and I only have 55,993 miles on the clock as it sits.
Here's a video of what happened:
http://www.youtube.com/watch?v=J1mQ7t4hfD4
I was doing a burnout. We'd splashed water under the tires. I pulled the handbrake all the way up. I rev it up, maybe to 4,000 or 5,000, drop the clutch, and give it some throttle. It lasted about a second. The car went a few feet, and the burnout just stopped. Obviously because power had been reduced.
We used a DiabloSport to scan the codes. It had 'system too lean' and 'MAF', which pop up a lot because of my aftermarket intake. But then it also had something like 'clutch switch'.
We took out the clutch switch, tested it, saw it was working fine, put it back. So we tried clearing the codes. Then the car wouldn't start AT ALL. Around this point I was pondering calling AAA.
Pulled the PCM fuse and put it back in. Now the car started- and with full power. But it still had the 'check engine light', so we scanned it again, and it had WAY MORE CODES. Maybe five or six of them. 'System too lean', 'MAF', I think 'Clutch switch', and two relating to the throttle, perhaps 'throttle position' and 'throttle (something else)'.
The car SEEMS to be driving fine and with full power, but I still have a 'check engine light' with all the error codes.
It would appear as if there is nothing mechanically wrong, but my engine's computer flipped out and is confused.
WHY would this happen, and how can I remedy it?
PLEASE offer some theories, advice, and solutions.
09-20-2009, 03:53 PM
#4
Senior Member
Join Date: 06-27-05
Location: southeast florida
Posts: 2,058
Likes: 0
Received 0 Likes
on
0 Posts
It is most likely to do with the throttle. I have been having that problem and have about the same miles as you.
Has to do with the throttle pedal position not corresponding with the throttle body position. i think it is covered under warranty.
If ur stuck just keep clearing the codes until it works again.
Has to do with the throttle pedal position not corresponding with the throttle body position. i think it is covered under warranty.
If ur stuck just keep clearing the codes until it works again.
09-20-2009, 03:53 PM
#5
Member
iTrader: (1)
Join Date: 08-01-07
Location: Rockford, IL
Posts: 318
Likes: 0
Received 0 Likes
on
0 Posts
how is it that 3 guys in the same day have the same problem without looking at the post below theirs....
the cure to this problem...........
STOP DOING BURN OUTS IN A FWD CAR AND HITTING THE LIMITER.
the cure to this problem...........
STOP DOING BURN OUTS IN A FWD CAR AND HITTING THE LIMITER.
09-21-2009, 09:10 AM
#7
Senior Member
iTrader: (3)
Join Date: 02-25-08
Location: Murray, KY
Posts: 2,534
Likes: 0
Received 0 Likes
on
0 Posts
What were the codes? Being an 05 your car could fall under a bad batch of PCMs that under certain conditions will throw a throttle body code and pcm code (driver 5 line 1 PCM or something along those lines...)
09-21-2009, 09:18 AM
#8
Senior Member
Join Date: 11-08-07
Location: Far from you
Posts: 5,792
Likes: 0
Received 0 Likes
on
0 Posts
My car has done this 3 times so far since I've gotten the car. My only advice is to disconnect the battery for 1-5 minutes and then reconnect. The codes should be gone. When this happened to my car, it was immediately after cranking... or lack of cranking up, I should say. It would also say the power steering was out, as well. It hasn't happened in about a year so maybe it's just a fluke with our computers. The first model of any new vehicle is always prone to malfunctions.
09-22-2009, 04:38 AM
#9
Senior Member
Thread Starter
iTrader: (2)
Join Date: 07-07-05
Location: Houston, TX
Posts: 799
Likes: 0
Received 0 Likes
on
0 Posts
New batch of problems today.
I thought the problem wasn't that bad because Saturday after resetting the PCM, the car drove home fine, and I drove it again later that night with no problems. The check engine light was on presumably with those same codes, but it ran normally.
Didn't drive it yesterday. Today I get in to go to university. To my surprise, no check engine light! I'm thinking the problem fixed itself.
After driving for a few miles, something goes wrong. I was coasting to a stop in neutral, not touching the accelerator, when the car starts revving itself up. It was a steady progression all the way up to 5,000- I had the realization that it wasn't going to stop so I freaked out and shut the car off.
I turn it back on, and turn around to go back home. On the way, it does the thing.
I get a ride to school, and when I get back, I try driving my car again. Check engine light is definitely back on- don't remember if it came back on this morning. After a few miles of driving, it does the same problem, steadily revving itself up uncontrollably.
When I get back on to my street, in second gear, I put my foot down just a little, just to see what would happen, trying to figure out what is it I'm doing that makes the car rev up. Well, I give it maybe a hard 1/4 throttle, revving up to about 3,000 RPM, when it goes back into ENGINE POWER REDUCED mode.
What's the problem and how can I get it fixed?
I thought the problem wasn't that bad because Saturday after resetting the PCM, the car drove home fine, and I drove it again later that night with no problems. The check engine light was on presumably with those same codes, but it ran normally.
Didn't drive it yesterday. Today I get in to go to university. To my surprise, no check engine light! I'm thinking the problem fixed itself.
After driving for a few miles, something goes wrong. I was coasting to a stop in neutral, not touching the accelerator, when the car starts revving itself up. It was a steady progression all the way up to 5,000- I had the realization that it wasn't going to stop so I freaked out and shut the car off.
I turn it back on, and turn around to go back home. On the way, it does the thing.
I get a ride to school, and when I get back, I try driving my car again. Check engine light is definitely back on- don't remember if it came back on this morning. After a few miles of driving, it does the same problem, steadily revving itself up uncontrollably.
When I get back on to my street, in second gear, I put my foot down just a little, just to see what would happen, trying to figure out what is it I'm doing that makes the car rev up. Well, I give it maybe a hard 1/4 throttle, revving up to about 3,000 RPM, when it goes back into ENGINE POWER REDUCED mode.
What's the problem and how can I get it fixed?
09-22-2009, 04:48 AM
#10
Senior Member
Join Date: 11-16-07
Location: Los Angeles, Ca
Posts: 6,232
Likes: 0
Received 0 Likes
on
0 Posts
sounds like one of your sensors are out of what...is there anyway that you can log your sensors while your driving so you could see which one is causing the problem....i know my scan tool has an option to record the sensors readings...does yours have that? this could help you pinpoint whats wrong...and if you dont know what your looking at...post the numbers that come up..
you should have readings like tps, map, maf, o2, ect, iat....
you should have readings like tps, map, maf, o2, ect, iat....
09-22-2009, 09:33 AM
#11
Premium Member
iTrader: (3)
Join Date: 08-21-06
Location: Western NY
Posts: 6,574
Likes: 0
Received 0 Likes
on
0 Posts
This sounds like it might be this Issue below
Service Information 2005 Chevrolet Cobalt | Cobalt, Pursuit (VIN A) Service Manual | Document ID: 1889565
--------------------------------------------------------------------------------
#07-06-04-003: LSJ, L61, LK5, L52, LL8 Engine - Reduced Engine Power, MIL/SES Light, DTC P1516, P2135, P2138 (Replace PCM) - (Jan 19, 2007)
Subject: LSJ, L61, LK5, L52, LL8 Engine -- Reduced Engine Power, MIL/SES Light, DTC P1516, P2135, P2138 (Replace PCM)
Models: 2005-2006 Chevrolet Cobalt, Cobalt SS, Malibu
2006 Chevrolet Colorado, TrailBlazer
2006 GMC Canyon, Envoy
2006 HUMMER H3
2005-2006 Saturn ION, ION Red Line
2006 Saab 9-7X
with ECOTEC™ 2.0L, 2.2L I-4 Cylinder Engine (VINs P, F-- RPOs LSJ, L61) or
VORTEC™ 2.8L I-4, 3.5L I-5, 4.2L I-6 Cylinder Engine (VINs 8, 6, S -- RPOs LK5, L52, LL8)
Attention: The following bulletin information is only to be used if the customer has returned for REPEAT repairs for DTCs P1516, P2135 and/or P2138.
--------------------------------------------------------------------------------
Condition
Some customers may comment on engine operation in the Reduce Engine Power mode with the MIL/SES light illuminated. This condition may be repeated and upon investigation, the technician may find the following DTCs set as current or in history:
• DTC P1516 Throttle Actuator Control (TAC) Module Throttle Actuator Position Performance
• DTC P2135 Throttle Position (TP) Sensor 1-2 Correlation
• DTC P2138 Accelerator Pedal Position (APP) Sensor 1-2 Correlation
Cause
This condition of a repeat DTC P1516, P2135 and/or P2138 may be caused by an internal concern with the PCM.
Correction
Important: DO NOT replace the APP sensor. Inspect the PCM build date first.
Before following the diagnostic information in SI on DTCs P1516, P2135 and/or P2138, an inspection of the PCM serial number year and Julian (PCM build) date will be necessary to determine if the PCM will need to be replaced to correct the repeat DTC P1516. Refer to Engine Control Module Replacement in SI in order to remove the PCM. Refer to the above graphic illustration (1) for the location of the PCM serial number.
The serial number is read left to right. The last digit of the year is the 9th character and the Julian date is comprised of the 10th, 11th and 12th characters and is used to determine the PCM build date. Refer to the example below to read a build date from the PCM serial number:
* 8 6 Y N AU K 1 5 3 2 5 0 R P N *
If the PCM year and Julian dates are between 5182 and 5304 , replace the PCM. Refer to the Part Catalog to order the correct PCM for your vehicle application, if necessary.
Vehicles with PCM built outside the dates should refer to SI diagnostics for DTCs P1516, P2135 and/or P2138.
Warranty Information
For vehicles repaired under warranty, use:
Labor Operation
Description
Labor Time
J6360
Powertrain Control Module Replacement
Use Published Labor Operation Time
Warranty Information (Saab U.S. Models)
For vehicles repaired under warranty, use:
Labor Operation
Description
Failed Object
Fault/Reason Code
Location Code
Warranty Type
Repair/Action Code
Labor Time
2481001
Powertrain Control Module Replacement
24810
67
0
01
01
Use Published Labor Operation Time
GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.
WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION
Š 2009 General Motors Corporation. All rights reserved.
Service Information 2005 Chevrolet Cobalt | Cobalt, Pursuit (VIN A) Service Manual | Document ID: 1889565
--------------------------------------------------------------------------------
#07-06-04-003: LSJ, L61, LK5, L52, LL8 Engine - Reduced Engine Power, MIL/SES Light, DTC P1516, P2135, P2138 (Replace PCM) - (Jan 19, 2007)
Subject: LSJ, L61, LK5, L52, LL8 Engine -- Reduced Engine Power, MIL/SES Light, DTC P1516, P2135, P2138 (Replace PCM)
Models: 2005-2006 Chevrolet Cobalt, Cobalt SS, Malibu
2006 Chevrolet Colorado, TrailBlazer
2006 GMC Canyon, Envoy
2006 HUMMER H3
2005-2006 Saturn ION, ION Red Line
2006 Saab 9-7X
with ECOTEC™ 2.0L, 2.2L I-4 Cylinder Engine (VINs P, F-- RPOs LSJ, L61) or
VORTEC™ 2.8L I-4, 3.5L I-5, 4.2L I-6 Cylinder Engine (VINs 8, 6, S -- RPOs LK5, L52, LL8)
Attention: The following bulletin information is only to be used if the customer has returned for REPEAT repairs for DTCs P1516, P2135 and/or P2138.
--------------------------------------------------------------------------------
Condition
Some customers may comment on engine operation in the Reduce Engine Power mode with the MIL/SES light illuminated. This condition may be repeated and upon investigation, the technician may find the following DTCs set as current or in history:
• DTC P1516 Throttle Actuator Control (TAC) Module Throttle Actuator Position Performance
• DTC P2135 Throttle Position (TP) Sensor 1-2 Correlation
• DTC P2138 Accelerator Pedal Position (APP) Sensor 1-2 Correlation
Cause
This condition of a repeat DTC P1516, P2135 and/or P2138 may be caused by an internal concern with the PCM.
Correction
Important: DO NOT replace the APP sensor. Inspect the PCM build date first.
Before following the diagnostic information in SI on DTCs P1516, P2135 and/or P2138, an inspection of the PCM serial number year and Julian (PCM build) date will be necessary to determine if the PCM will need to be replaced to correct the repeat DTC P1516. Refer to Engine Control Module Replacement in SI in order to remove the PCM. Refer to the above graphic illustration (1) for the location of the PCM serial number.
The serial number is read left to right. The last digit of the year is the 9th character and the Julian date is comprised of the 10th, 11th and 12th characters and is used to determine the PCM build date. Refer to the example below to read a build date from the PCM serial number:
* 8 6 Y N AU K 1 5 3 2 5 0 R P N *
If the PCM year and Julian dates are between 5182 and 5304 , replace the PCM. Refer to the Part Catalog to order the correct PCM for your vehicle application, if necessary.
Vehicles with PCM built outside the dates should refer to SI diagnostics for DTCs P1516, P2135 and/or P2138.
Warranty Information
For vehicles repaired under warranty, use:
Labor Operation
Description
Labor Time
J6360
Powertrain Control Module Replacement
Use Published Labor Operation Time
Warranty Information (Saab U.S. Models)
For vehicles repaired under warranty, use:
Labor Operation
Description
Failed Object
Fault/Reason Code
Location Code
Warranty Type
Repair/Action Code
Labor Time
2481001
Powertrain Control Module Replacement
24810
67
0
01
01
Use Published Labor Operation Time
GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.
WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION
Š 2009 General Motors Corporation. All rights reserved.
09-22-2009, 01:26 PM
#13
New Member
Join Date: 02-20-08
Location: CICERO IL
Posts: 82
Likes: 0
Received 0 Likes
on
0 Posts
This hapen to me to dont no what wrong with it i took it to the dealer and the told me that there was lot of air goin inn to the engen but they didnt no y i think it bcuz i have the stage 2 pully and ingeters so they told me it had to be caliberit but the dont no if that the problem with it yet the try dyno it but they cant cuz the car dont go over 3,00rpm so i going to get it caliberit to c if that what wrong with it my car been down over 2month hopefully that is it
I took it to autozone and scan it and this or the code they scan P0068 AND P0230 CAN SOMEONE TEL ME WHAT THEY OR PLEASE
I took it to autozone and scan it and this or the code they scan P0068 AND P0230 CAN SOMEONE TEL ME WHAT THEY OR PLEASE
Last edited by COBALTSS2.0; 09-22-2009 at 01:26 PM. Reason: Automerged Doublepost
09-22-2009, 01:31 PM
#14
Premium Member
iTrader: (3)
Join Date: 08-21-06
Location: Western NY
Posts: 6,574
Likes: 0
Received 0 Likes
on
0 Posts
This hapen to me to dont no what wrong with it i took it to the dealer and the told me that there was lot of air goin inn to the engen but they didnt no y i think it bcuz i have the stage 2 pully and ingeters so they told me it had to be caliberit but the dont no if that the problem with it yet the try dyno it but they cant cuz the car dont go over 3,00rpm so i going to get it caliberit to c if that what wrong with it my car been down over 2month hopefully that is it
I took it to autozone and scan it and this or the code they scan P0068 AND P0230 CAN SOMEONE TEL ME WHAT THEY OR PLEASE
I took it to autozone and scan it and this or the code they scan P0068 AND P0230 CAN SOMEONE TEL ME WHAT THEY OR PLEASE
Are you ****** kidding or what??? Do you seriously talk like you type..... or is english your 2nd or 3rd language ?
09-22-2009, 05:30 PM
#15
Senior Member
Thread Starter
iTrader: (2)
Join Date: 07-07-05
Location: Houston, TX
Posts: 799
Likes: 0
Received 0 Likes
on
0 Posts
Unfortunately, I'm also throwing a fourth code, regarding the clutch switch. So who knows what more could be wrong.
Importantly: where is a good place to take my car that isn't the dealer?
Thread
Thread Starter
Forum
Replies
Last Post
Extreme Dimensions
Appearance
53
06-29-2016 11:01 AM