2004 Chevy Tahoe reduced engine power

[rtcmom1]

Hi there. New to this forum and having great frustration with my Tahoe. We are at about 200,000 miles now. It has the 5.3 liter engine. For at least a year we have been having this reduced engine power message when I am trying to start the engine. It takes about three or four times jiggling the battery cables to get the message to go away and for the vehicle to start properly. It's even worse when it is cold. Once it starts and the engine warms up, it runs fine for the rest of the day. I have replaced the TCM, the throttle body x 2, throttle body harness, replaced the pig tail on the throttle body connector, replaced the battery, replaced the ignition switch, and the little red box where the battery cables connect to (sorry I can't remember what the mechanic called it). At least 2500$ worth of replacement parts + work, and still with the reduced engine power message. Two different mechanics, both frustrated as I am. I have been reading the forums and using advice I have seen to help the mechanics troubleshoot. I have not replaced the APP sensor or the gas pedal assembly yet. It makes this noise on start up that sounds like a compressor starting up or something firing up and until that noise is heard the reduced engine power message will not go off, and the truck will not accelerate at all or only about 20 mph. I can reproduce the sound almost identically when I switch on my heater. Also, sometimes the car will not turn off unless I turn on the bright lights. Please tell me it is something obvious. Fuel injectors? And I am a girl so please keep it simple, LOL. Thanks for your help!

 

[gmtech4]

Hi there. New to this forum and having great frustration with my Tahoe. We are at about 200,000 miles now. It has the 5.3 liter engine. For at least a year we have been having this reduced engine power message when I am trying to start the engine. It takes about three or four times jiggling the battery cables to get the message to go away and for the vehicle to start properly. It's even worse when it is cold. Once it starts and the engine warms up, it runs fine for the rest of the day. I have replaced the TCM, the throttle body x 2, throttle body harness, replaced the pig tail on the throttle body connector, replaced the battery, replaced the ignition switch, and the little red box where the battery cables connect to (sorry I can't remember what the mechanic called it). At least 2500$ worth of replacement parts + work, and still with the reduced engine power message. Two different mechanics, both frustrated as I am. I have been reading the forums and using advice I have seen to help the mechanics troubleshoot. I have not replaced the APP sensor or the gas pedal assembly yet. It makes this noise on start up that sounds like a compressor starting up or something firing up and until that noise is heard the reduced engine power message will not go off, and the truck will not accelerate at all or only about 20 mph. I can reproduce the sound almost identically when I switch on my heater. Also, sometimes the car will not turn off unless I turn on the bright lights. Please tell me it is something obvious. Fuel injectors? And I am a girl so please keep it simple, LOL. Thanks for your help!

 

Wow, you need some education on how stuff works ,,,,,,,, that msg means there is a trouble code (DTC) it needs to be pulled from the PCM and diagnosed , it's very simple to do , if you have the knowledge , your shop does not have these skills ,

 

Unfortunately you have HEMOURAGED way to much cash and you actually researched this TO TELL YOUR SHITTY TECH what to do ,,,,,, after all this you find this site , and now out of money and looking for Devine intervention and a free fix that the Internet can provide .......

 

Sorry doesn't work that way

 

You don't have a TCM unless it's a diesel ....

 

Stop this madness and change shops ... Maybe a dealership that may have some experience fixing your GM truck

 

Sweet jeeeebus girl

[rtcmom1]

Well thank you for a response anyway, LOL. Maybe TCM is not the correct name for the thing that's just what I remember. I took it to a GM dealer repair shop first. Told me I needed to replace my engine and I did. 3000$ later....still the same problem. And when I took it back all they could say was well sorry but we don't know what the problem is. The codes they were getting and my new mechanics as well are all throttle body codes. again thanks for the reply as harsh as it was. Just looking for some tips you know try this try that.. Peace! T

[rtcmom1]

If the engine starts when you wiggle battery cables, I'd have to say you've found the problem ... ??

. Well no... Because we replaced the battery cables and battery and it still does the same thing.

[rtcmom1]

I'd definitely say it is something electrical. Check your grounds on your battery and BCM.

.

 

Thanks will try this!

[cashflow50]

I had the same problem a few years back on my 03 yukon.

 

ACDelco 214-1105 Vapor Canister Purge Valve

 

I changed the o-ring to the above mentioned and the monster has power again. I found this with extensive searches on the infamous 'reduced engine power'. I've tried all the Throttle body to pig tails. all of them looked fine without any cracks or what not. All along it was an o-ring for the ACDelco 214-1105 Vapor Canister Purge Valve. Check that first before anything. Cost me about $2

[gmtech4]

YOU REPLACED THE ENGINE ????

 

You are the biggest idiot I've ever heard about here in 8 years ... Swear to god .... You need more than harsh ....

 

 

Omfg !!! I will tell stories about you at work lmfao !!!!!!

 

Why did you not go back and have your money returned ....ITS CALLED A COME BACK !!!!!

 

They miss diagnosed it for cryin out load ,,,!!!!!! I'm stunned

[Jsdirt]

If the engine starts when you wiggle battery cables, I'd have to say you've found the problem ... ??

[08CHEVYMAN]

This is sad.. All shops are doing to this poor gal is stealing money if you wiggle the connectors and it runs WHY would you need to replace the engine

 

 

Sent from my iPhone using Tapatalk

[02suburbanZ71]

I can feel robs pain.

[sahls01gmc]

I'd definitely say it is something electrical. Check your grounds on your battery and BCM.

[Jsdirt]

This is why nobody I know would ever bring a vehicle to any dealer, aside from a couple of the Jap manufacturers. They have a reputation of gouging around here that goes back decades.

 

It's nothing personal, rtcmom1 - we see stories like this all the time here, and it makes our blood boil! Hate to see people waste money like they do - it happens CONSTANTLY ...