GMC Yukon Reduced Engine Power message
I purchased my 2006 Yukon last September 2005. I now have 24,000 miles on it. Over the last month I have had it into the dealer three times for the same problem. The problem is that while driving the vehicle it will suddenly lose almost all power. The Information Center will display the messages: "Stability Control Disabled", "Engine Power Reduced". And the vehicle will not go over 20 mph on a level surface and bearly 3 mph up a moderately steep hill. Each time I have had it into the dealer for repair they have beeen stumped by what the cause of the problem is. They said that GM/GMC told them that "GM is aware of the problem but does not have a fix for it at this time". How can a manufacturer sell a vehicle that has a defect and not have a fix for it? When the power goes out in a busy intersection or on a highway this is a major safety issue. Has anyone else experienced this problem.
Thanks, Steve
See Also: Reduced Engine Power Message Displayed on GM Vehicles
Thanks, Steve
See Also: Reduced Engine Power Message Displayed on GM Vehicles
2
Comments
You need to be CAREFUL!! Mine was fine for a week and then went nuts again with all the kids in the car. Mine was in the shop for a week...ran fine for a week and then died again. Seems like whenever they mess with the wires it behaves for a little while. Dealership is NO help...GM is NO help...I have no idea where to turn at this point. I have a beautiful vehicle...sitting in the driveway, can't use it. GM and the dealership didn't seem to give a damn that this is a MAJOR safety concern...in fact when I called the dealership this morning I was so upset I was crying...the manager said that he "didn't like the way I was speaking to him" and said there was nothing he could do for me. I wasn't even letting him have it! I am SO fed up and confused. I even went to a FORD dealership today to see what they had that actually ran and stayed running...only found one SUV I liked enough to test drive...but all I did was bring it home, park it next to my Yukon, and make fun of it...I hated it...I just want my Yukon. If you find any further info on this please let me know. There are several TSBs regarding this issue but GM didn't seem overly impressed with that either. Hopefully someone will be able to solve this problem. Stephanie :lemon:
please check this site and you will find a complete conversion kit available to you ...hgb
I also have a 2003 Yukon. I have had the engine light on the last few weeks, have had it diagnosed, One place stated it was Fuel Pump and Fuel Filter, another o2 Sensor and another Mass Air Flow Sensor. I replace Fuel Filter. Light went away for a while. Its back on I had it diagnosed after unpluging the MAF Sensor and it gave the same codes as a bad MAF Sensor. This morning I went to start my car, it started then stopped, and the code that you all are talking about speared for the first time. Reduced Engine Power, and it will not start. Can anyone tell me what ground wires were found bad, or if anyone has a fix to get the vehicle started?
Thanks
Brian
I just wanted to share with everyone with the problem that I had with my 2003 1500HD Crew Cab with 6.0 Liter. My truck would go into reduced engine power off and on. Sometimes one a week, sometimes 5 times on a 20 mile trip. My problem was a broken wire on the plug in going in to the throttle body. In the picture is the plug in that had caused me all of my pain and grief....... My problem was very intermittent and was hard to diagnose. I started vehicle and with all codes clear. I wiggled the wiring harness in the picture and vehicle spit and sputtered, throwing it into reduced engine power mode, and then smoothed out to a smooth idle. I disconnected the plug and pulled wires out of plug end and found a broken wire. Mine was a brown wire with white stripe. BUT, what was interesting, was that this vehicle had apparently had the smae problem with previous owner, becuz there was another wire (yellow wire) right beside the one that I found broken already soldered up and taped from where it had apparently happened before. This was my problem and not my truck is running great, and actually even idles better that before. Hope this helps with any problems that anyone else is having. I know this problem can be very irritating.
http://i184.photobucket.com/albums/x191/bunchtst/BrokenWire.jpg
Frustrated I told them to look at it and fiqure it out. I searched out the best mechanic and he was knowledgeable and worked on it. Said it was a bad ground , charged me 80 bucks and I was on my way. Problem was 5 miles down the road i got reduced engine power again. Turned around and took it back to them. long story short they had it for a week and said they could not fiqure it out . they wanted to throw parts at it starting with a 400 dollar one. I read your thread and told them to check out the wires at the throttle body, they told me they already did, and refused to look at them again. I went and got the truck and decided to go with your suggestion , took apart the cannon plug and found NO broken wires. Decided to replaced the metal contact pins themselves. cut them off and went to a different dealership to parts and look thru a ton of contact until i found the exact ones. replaced them and soldered them just in case and I HAVENT HAD THE PROBLEM SINCE. Im guessing it was just a bad contact pin, just enough to trip the computer.
Thanks for the info , your time writing your thread probably saved me hundreds of dollars.
FYI
I have never taken a vehicle in my entire life to a dealership for repair , they are thiefs. Look and ask around for a local repair shop with a good reputation. you will save alot of money, and I am NOT talking about a Firestone or something like that, more of a mom and pa shop
BTW,,,,,,,,,,,,I am a american airlines aircraft mechanic for the last 20 years
AC Delco
ACD# PT1572
GM# 88986255
Hope this helps.
Of course, this problem started about 4000 miles after warranty expired.
When I contacted GM they really just did not care. This issue shows up in the TSBs but what it comes down to is this: Until it kills someone, they won't do anything. I'd really like to know if this has been the cause of any serious accidents. If GM knows, they aren't talking.
Best of luck to you. I know how frustrating this problem is and I don't wish it on anyone.
I got truck home (at 15 MPH!) and started to examine wiring harness that plugs into the TPS. On my truck, the yellow wire was worn through and is shorting out. A simple wiring connector was the solution, rather than a $260 part. I encourage anyone to check wiring first.
I just had the problem again!!!@! unbelievebly fustrating.
are you saying that you replace this connector ACD# PT1572 and the wiring to fix the problem???? It was not the brown or yellow wire on the other side??
I am ready to dump this thing.
Btw did the wiring come with this connector or is this the price for just the connector??
Thanks,
John
This is what I replaced. Click on the link below and see the plug-in. The connector comes with about 15" or so of "ALL WHITE WIRES". You need to replace one at a time so you do no get them crossed. It comes with 8 wire conectors also. I am not saying that your problem was the same as mine, but its possible. The main reason I went ahead and changed out the whole plug was because the wire was broke off about 1-1/16 from where the wire went into the connector and it made it hard to get a good solder job on the broken wire. I would recommed again wiggling wires with the engine running and have someone sit in the vehicle and let you know when it goes into Reduced Engine Mode. Its best to do it this was that way you know which wires you moved to create the error. Let me know if you need more help. I ll help if I can.
http://198.208.187.182/internet/ViewPartImage.jsp?acdelcoPartNumber=pt1572
The dealership wanted to replace the tac module on the firewall. But after I thought I had fixed it when I replaced the brown and yellow wire ends that connected to the trottle body and had 2 months of success I fiqured it had to have something to do with that. I ended up replacing the throttle body. The cheapskate in me found one in a junkyard on a totaled out yukon. It cost me 175 shipped to the door. Replaced it in about 20 minutes, and it fired right up. Runs like a champ.
I am hoping this solves the problem and not just another teaser for a couple of months.
My wife called on her way home and had the "REDUCED ENGINE POWER" message and the check engine light was on, 2003 GMC Sierra 1500, she did not think she would make it home, just a few blocks away. I checked the net and found this post and started checking at the battery and almost right away found that the negitive battery lead was not tight where it connects to the block, it was not arcing loose, just not snug, a 1/2" wrench to thighten the bolt and the engine idle returned to normal, the message and check engine light is off and it drives normal. Thanks for the help!!!
-Replace wire harness to throttle body (get the AC Delco OEM harness) probably
This is from GM:
The PCM detects that the commanded and actual throttle positions are not within a calibrated range of each other.
The above condition is met for less than 1 second.
Step 1. Tighten ground G103 located next to the right cylinder head (passenger side) just below the head and mounted into the block. The ground uses a 13 mm bolt head mounted vertically to the engine block just above the bell housing. G104 located behind the left cylinder head has also been found to cause this concern.
Inspect throttle body torque. If the throttle body is improperly torqued to the intake manifold, remove throttle body and retorque the throttle body mounting nuts per SI in a two step process: 45 lb. / inches. on the 1st pass, and then 89 lb. / inches on the final pass.
Verify all electrical connections especially right at the TAC module. There have been reports of the plastic retaining tab in the connector missing causing poor contact especially on rough roads
Road test vehicle to determine if code re-sets/condition re-occurs. If not return it to customer.
Step 2. If condition is not corrected using above procedure, or re-occurs, replace throttle body assembly.
I didn't know that car came with a Driver Information Center (DIC). Are you sure you're just getting a "Service Engine Soon" light or can you actually read, "Reduced Engine Power"?
Those cars didn't use electronic throttles, at least I didn't think so.
Thanks to all
I thought we were going to be involved in a horrible accident today on the highway... YES, this happened on the highway and we had an 18-wheeler baring down on us with no where to pull off... I did have the forethought to put on my hazards, and most people were able to change lanes and pass us... but the 18-wheeler could not move over, and for some reason was refusing to slow down at a more reasonable speed... he was inches from my bumper before he finally changed lanes... I had 3 of my 4 children with me, all under the age of 5 in carseats... I was so scared...
I cannot believe GM has not recalled or addressed this problem proactively... They will be hearing from me via certified letter...
So thank you EVERYONE, but most especially, you... you covered all the bases for us... and lastly, I'm sure you saved us a bundle of money, something we cannot afford to be frivolous with these days...
Laura (mom2four)
Just for reference, one time I left the cap off, my Check Engine light came on before I was even out of the gas station parking lot. After I put the cap back on, less than a mile, the Check Engine light went off by itself...
SPOT ON WITH THE HARNESS!!!!!!! My wife called today with the "reduced engine power" alarm. She restarted it and got it home. I found this website and this post. Took note and went to the connector. moved it around an got the same error. went and looked......YELLOW WIRE WAS BROKE!!!. Now, it looks to be about a 8 strand wire which was bent at the connection. I think that they should have used wire with more strand and made it longer to reduce the "KINK". I soldered a long piece in with more strands. Problem fixed.
THANK YOU GUYS!!!!!!!!!!!!!!!!!!!!!!