(Help) how to get my car out of reduced power mode

I do not that, not until 2006 the bad octane spark table on the PCM was terrible, and would force the car to run in reduced power mode. for the P 1125 IT may be your Throttle Position Sensor, 04 to 08 grand Prix uses a drive by wire system.( There's no Cable to control your throttle, its a sensor on your gas pedal, electronically controls the throttle body) You have a multi level sensor system on your actual gas pedal inside the car. and you have a drive by wire sensor to control your butterfly on the throttle body. I would start with getting that issue addressed, hence that's your only codes your PCM is throwing at you. You can get a replacement at your local auto store for around $100, and YouTube a howto video to install it for free. should take about 1 hour.

ok Jae thanks my mechanic is saying the computer is bad the position sensor is new the dealer replaced it recently trying to fix the problem. looks like i might just order a computer there on ebay for 80$

That's odd. The computer going bad is a VERY RARE occasion. Did you run the car through 3 complete drive cycles? ( 3x Cold start, until warm and driving, repeat) ? Also clear all of the fuel trims, and cache by disconnecting your battery for 20 minutes? Before you replace the computer, you may be able to get the computer flashed at the dealer for cheaper than $80. Flashing it will pretty much have it brand new.

Did any of this stuff ever work? I'm having the EXACT same problems with my 2005 grand prix, but don't know if it's the computure, tps, or something else. Email me if anything fixed it. cts3w@mtmail.mtsu.edu

Had this issue with my 04 Grand Prix. When in park, I'd press the accelerator and it wouldn't get past 1300 RPM. When driving, we would have to take off very slowly after a complete stop and even then, couldn't go past 65 mph. Replaced the mass air filter, the computer, and pedal/accelerator position sensor. None solved the issue and the car would still show the "reduced engine power failure" thing. Finally took it to some dude that had a $6k computer error reader thing and it came up with the throttle bottle assembly. After spending money on all this other stuff we said why not, so we went ahead and changed it. It cost a little over $300 at the local auto parts store ao we went to a junkyard/you- pull-it place and found the car we needed. We took it off right then and there. It doesn't take but 10-15 minutes to get out and put back in. all you need is a 10mm socket and git r done!! Sparked up the car and BAM!! We were able to press the gas and it picked up right away. It's been working fine for a small trip now and looks like this fixed the problem!! It was the throttle bottle assembly. When we took the original one out, the gasket was totally worn out and looked pretty ugly. That may have been it but just replaced the whole thing. Good luck!!

If youfind out what it is plz email me and let me know what it was my car is doing the same thing and they are telling me that is the sensor above my peddal my email is carieo44@gmail.com thank you

Anyone ever above the problem , I have replaced the pedal and throttle body no fix

Ok i need help. My 06 Pontiac Grand Prix base, 6 cyclinder is losing power as i drive and sometimes it dies on the street. One parts store said it has 2 throttle body sensors. I went to a very good friend who owns Napa and there is not a throttle body sensor on that year. I need help. I am thinking it is a accelerator pedal position sensor. HELP

Ok I had the same issue with reduced engine power code and car shutting down while driving. Once I start it back up it accelerates very slow even when mashing in gas pedal. I changed the throttle position sensor first. Unfortunately couldn't get the sensor by itself had to buy entire assembly (took me 15minutes). That didn't fix it so I replaced the accelerator pedal sensor which included the pedal (took me 10 minutes). Problem solved. Not saying it will resolve your issue but it fixed mine!! No mechanic needed don't get taken to the bank. Look up the YouTube video and do it your damn self. Good luck and hopefull this helped.

PLEASE HELP: I have a 08 Pontiac Grand Prix...replaced accelator pedal position sensor and it's still messing up, and getting worse. Car has cut off on me 4 times today. Mashed the pedal all the way down and barely went any where.

Can u flash the pcm ur self or do u have to go to a dealership and how much does it cost

If what i suggested in order doesn't work. Replace the throttle body. The sensors are built in and cannot be serviced. Entire assy replacement is required. The control works at both ends ( pedal sensor and throttle body). Remmember its electronic theres no cable. They did this to fix delay and VE. Good luck!

Ok I have a 2004 pontiac grand prix and keep saying reduce engine power so I changed the throttle body drove go for two weeks and started back saying reduce engine power so I changed the accelerator pedal position sensor so I'm hoping that it's if not I give up

05 grand prix went into limp mide then wouldn't start. 10 codes came up. Replaced throttle body and pedal position sensor. Didnt fix anything so i cleaned old throttle and reinstalled it along with pedal. Everything and everyone points to the computer. I searched and found 2 melted wires and 2 completely broken wires. Car runs great and all codes are gone

Where did you find those bad wires?

They were to the right of the oil fill cap. I lifted and inspeced underneath the wire harnesses. So top right side of valve cover was where they were melted.

Directly under the black tape. Notice the oil rubbed away underneath. Thats where the wire harness was touching the valve cover.

Check the Vacuum line off the intake. That's What happened to mine!

I had one last year that did that and I changed the fuel pedal out and it quit doing it a quick way to test it when it goes into limp mode tap the side of the fuel pedal with a screwdriver and see if it don't rev up after that

Ditto to the problems.. 04’ Pontiac Grand Prix gtp1 3.8L I felt reduced power and misfires. Scanned. Got codes for both o2 sensors. Checked sensor 1. It’s wires were cut clean, along with the spark plug wire for cylinder 6. I spliced all those wires back up. Engine sounds healthier, occasional misfire, but smoother. Still reduced power. I reset the ecm by pulling the neg off off the battery for 30min. Still reduced. Replace the throttle body unit. Replace the accelerator pedal. Now, I’m getting all kinds of codes P0300-misfire P0108-MAP sensor P0036-o2 sensor bank 2 P1125-APP sensor AND P2138- APP sensor and TPS sensor not correlating. I clear the codes. Reset the system and try again. Limp mode enables about 30-35mph after switching out of 2nd gear.

Seeing all of your guys prices to fix things is freaking crazy yo.. I’m jealous.. I found a TP/w sensor on Amazon for $945 lmao.. CARID for $450.. EBay for $130(lowest) I’ve got the same issue.. P0300-misfire P0036-o2bank2 P2138-non correlating Voltage between APP and TP sensor P1125-non correlating Voltage between APP and TP sensor I had a cv axle slip out of the knuckle a month or two ago, and ever since it had reduced power. Replaced the cv. Still reduced. Cleaned TP/w sensor Still reduced. Replaced the TP/w sensor Replaced the APP unit. I didn’t do such an in-depth reset of the system though. Gonna have to try that tomorrow. Probs gonna be looking around at my wires too..

Idk if this will help anyone but I’m going to try it tomorrow.