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05 Escalade ESV
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Discussion Starter #1
yesterday was out driving all of a sudden in the middle of a hill the car would not move. next thing I know I get the good old reduced engine power, system stability messages and the TC light on the dashboard lit up. Could not get the car to go any further up the hill was stuck in the middle had to call a tow truck. Everything I read says the throttle body mechanic says there's a sensor that goes with the throttle body and the car threw a code for it what is the possibility that it's only the sensor and not the whole throttle body?
 

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03 cadillac escalade
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The throttle body is worked via the pcm and would throw a code of it had a issue(same with the data link to the tac module)

Now it will cause a reduced engine power message and still let the engine run(you just don't get the full range of the throttle)

There are five sensors total
Three in the throttle body
Two mounted on the side of the pedal in a single package unit
There is also a module the the sensor on the pedal reports to called the throttle actuation module(or tac for short)
If any of these sensors are failing or going flaky it will trigger the reduced engine power mode
Failure of the data bus to the pcm(power train control module) from the tac will also cause the reduced engine power message to show and will also disable the starter and fuel system

If the sensor code in the pcm is for the throttle body sensors then the whole throttle body has to be replaced as the sensors are internal and not serviceable
 

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Pcm......Power Control Module. It's basically the computer that controls the fuel injection system and all other systems that make the engine run.
 

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03 cadillac escalade
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blaze190 said:
Pcm......Power Control Module. It's basically the computer that controls the fuel injection system and all other systems that make the engine run.
Correction it's
Power train control module
It works both the engine and transmission along with acting as a gateway for the throttle control module

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Cadillacnewbie16054 said:
No the engine didn't shut off. There messages pop up when I put my foot on the pedal and shift into drive.
Sounds like the pedal position sensor

Need to get the codes pulled as it likely has thrown a code for the sensor
 

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08 Escalade ESV awd, 05 Yukon Xl Denali awd, 06 SRX sold
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I would start with having the vehicle scanned and see what trouble codes a present then go from there
 

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My started doing this but it's for a few secs then I can drive. I thought it's because my hub is making noises and that I know there is a sensor on it. I'm changing the hub today after work. So do I have a bigger problem also?
 

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joelnaimee said:
My started doing this but it's for a few secs then I can drive. I thought it's because my hub is making noises and that I know there is a sensor on it. I'm changing the hub today after work. So do I have a bigger problem also?
The wheel speed sensor is on the wheel hub
 

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That's why I thought it's why as causing the problem. I figured the sensor is going bad and making the truck think it's skidding. It's acting like I'm sliding on ice
 

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03 cadillac escalade
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Easy way to tell for sure is disable the traction control(little button with the car on it)
If the truck runs fine with it off then you will need a tech-2 to tell which wheel speed sensor is failing

Mine does it ever so often(plus the bearing is starting to moan slightly) just waiting till it gets worse before dropping the cash on it as currently it's not affecting the truck's proformance
 

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Sorry I didn't use complete laymen's terms on the PCM comment. I didn't mention the Trans part of the module because his problem at that point sounded most likely a power train problem and not a drive train. Plus the throttle control is part of the efi system. Without throttle position info the efi system wouldn't know how to function in off idle situations.
 

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I changed the hub and everything went back to normal. Even the weird braking issue when tuning into a parking spot and the brakes get hard. So my problem was all centered around the wheel hub sensor.
 

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2004 Escalade ESV 2008 Escalade ESV
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Hello,

I had the same exact thing happen on my way to work this morning. On the interstate cruise was set at 60 mph. The cruise kicked off and I got reduced engine power message along with the traction control light and check engine light came on as well. I read some of the other posts and turned the traction control button off. I proceeded to work (about 5 miles from when it happened ). All lights stayed illuminated. When I stopped at a light or stop sign idling got rough like it was going to shut off so I put it in neutral and kept the idle up. Made it to work. 8 hours later I got in the truck to drive home ( about 12 miles). Only the check engine light was illuminated. The truck drove fine to my doctors office. I then drove home. When I cranked it up the last time to put it in the garage until I can take it to the shop I had no lights at all. The check engine light had gone out. Are the codes still stored even though the light is not on ? Also the throttle body and connector were replaced with OEM parts about 9 months ago. Do you guys think it could be the throttle body again? I hope not because the last one cost about $900
 

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hturner0iii0 said:
Hello, I had the same exact thing happen on my way to work this morning. On the interstate cruise was set at 60 mph. The cruise kicked off and I got reduced engine power message along with the traction control light and check engine light came on as well. I read some of the other posts and turned the traction control button off. I proceeded to work (about 5 miles from when it happened ). All lights stayed illuminated. When I stopped at a light or stop sign idling got rough like it was going to shut off so I put it in neutral and kept the idle up. Made it to work. 8 hours later I got in the truck to drive home ( about 12 miles). Only the check engine light was illuminated. The truck drove fine to my doctors office. I then drove home. When I cranked it up the last time to put it in the garage until I can take it to the shop I had no lights at all. The check engine light had gone out. Are the codes still stored even though the light is not on ? Also the throttle body and connector were replaced with OEM parts about 9 months ago. Do you guys think it could be the throttle body again? I hope not because the last one cost about $900
Get the codes pulled
Likely a wheel speed sensor by the way you describe it
 

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I see that this is an older thread, but it is still a relevant issue. I was having the dreaded reduced engine power on my 03 Escalade. In the summer it would only do it when it want warmed up before driving; but once it got cold it was doing it every 2 miles, making it a much bigger issue and ruining the driveability of the truck. Long story short, I've fixed the problem (finally...) I did a lot of research on forums like this and ended up replacing the throttle body and attached sensors, the APP sensor (accelerator pedal position sensor,) and the TAC module ( throttle actuator control.) After spending only about $300 dollars and acquiring said parts, I took it out for a drive and finally... I can drive my truck again. This was an extremely frustrating journey for me as I'm sure it is with everyone else who may be experiencing this huge issue. Hope this helps. -Sam.
 

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09 cadillac cts4 09 yukon Denali
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If you get lose of power its not speed sensor. I have had to replaced probably 10 to 15 wheel barring in my life never got lose of power.
Its most likely throttle position sensor.
It happened to me in 09 Yukon Denali. Every light goes on and it drives like your catalytic converter is plugged. You can press on gas but it barely moves. The motor is in limp mod not letting you go faster.
Easy fix its on throttle body i did it in 5 minutes in -25. I did not take off throttle body like you see people do on YouTube Google
Sorry how ever paid $900 acdelco part on ebay $125. If live buy me i would do it free. If part was same price i would rather replace throttle position sensor than air filter in my denali
 
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