Question about 2004 GMC Envoy

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Service engine light keeps coming on

My 2004 envoy 'reduced engine power' light came on and the car cut off several months ago. It started right back up and it never happened again but now my service engine soon light comes on from time to time. Sometimes I can take the gas cap off and put it back on and the light goes out. But then it may come on again in about another week.

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Need to scan for codes and find problem code some part stores do for free

Posted on Jul 06, 2009


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The engine light in the 2004 Envoy stays on and the reduced engine power light

You may need to find a different shop

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Reduce engine light came on in my 2002 envoy and it feel as if the truck is not getting any power, why is that? the truck slowed down so i pulled over cut it off an started it back up. after starting back...

Reduced engine power is just like a safe mode. First things first, clean your throttle body. It's possible the butterfly is sticking. Disconnect the battery, clean your throttle body with throttle body cleaner, must be nice and shiny. When finished, drive around for 20 minutes or so with all accessories off. This will allow the computer to relearn a properly functioning throttle body.

Mar 25, 2011 | 2002 GMC Envoy

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My service engine light has been coming on for a while and now I was stopped at a light and my car killed the light Reduce engine power light came on what do you think it is?

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Jan 06, 2011 | 2004 GMC Envoy

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My fan clutch is trying to go dead and it made my service engine light come on and now my reduced engine light came on what should i do

First you need to determine what the fault codes are that are setting the check engine light, if it is pointing to the fan clutch, have it replaced. But I don't think a bad fan clutch will set the reduced engine power light, there may some other things going on, the codes should help.

Oct 22, 2010 | 2004 GMC Envoy

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My 2004 envoy had a light come on that said reducing engine power and then the oil pressure dropped and die but it started back up and everything was fine then it did it again the next day what is the...

Your engine oil pump could be going bad and when your oil pressure drops your engine computer puts the car into a (Limp Mode) so you can safely find a place to pull over to prevent any permanent engine damage. Have your oil pump checked and replaced if necessary.

Jun 15, 2010 | 2004 GMC Envoy

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Car keeps stalling out along with reduced power and check engine

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May 14, 2010 | Cars & Trucks

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disconnect batt. for 30 min. then reconnect,if no problem exist the lights will go away

Dec 20, 2009 | 2003 GMC Envoy

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SES light then Reduced engine power light, loss of engine power

Hi It me Mohammad Siddiq my dear. First of all it will be wise of use to take your vehicle to a dealership or any other fully equipped w/shop. They can better tell you what the fault your vehicle has. But at the same time if your friend has the same model vehicle so you can exchange some parts with that vegicle, e.g., Mass Air Flow or TPS (Throttle Position Sensor) and can check your vehicle. These parts do not need to be programmed with scan tool. Just Simply replace these parts and switch on the ignition and wait for 01 minute, then switch off for 30 seconds and then start the engine. Now road test your vehicle, if no SES light or reduced power then there was fault with the part/s replaced. So Return those parts and now you must replace these parts with new or used ones. Anything else I may be contacted on my yahoo id [email protected]. Thanks. I am an auto technician and working in a GM dealership in Saudi Arabia. I am from Pakistan.

Apr 28, 2009 | 2004 GMC Envoy

1 Answer

I backed the 2004 envoy into my driveway and the engine killed and the reduced engine power light came on along with service engine light also. Restarted the engine and had no throttle while in park...

You need to check the fuel injection system, throttle body, sensors, check harness for ground. Best solution is to have your engine scanned using Tech 2 scanner. The mechanic will advice you based on the scan code. Whenever the "service engine soon " light the computer system logs the error code. You can retrieve this error code using a scanner.

Apr 28, 2009 | 2003 GMC Envoy

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