Question about 2002 GMC Envoy

1 Answer

Envoy 2002 unsteady RPM and engine while stoping

I have a problem with my 2002 envoy which I never faced before. The problem is that when I start the engine, it will start smoothly but after a while the RPM is start oscillating up and down and the engine is not stable and when I drive no problem and the RPM is stable and the engine is raunning well, but when I stop for a trafic light, then the RPM start moving up and down and also the engine is not stable as well. I've sent my car for fixing to different places but they are not able to know the reason. The problem appreas only when the car is stopping, While running no problem at all. Please advise

Posted by on

  • maher_assaf Dec 01, 2008

    Actually, my mechanics finally found that the problem was from the camshaft exhaust sensor which was not working. we changed it, then the car is running fine



1 Answer

  • Level 1:

    An expert who has achieved level 1.


    An expert that hasĀ over 10 points.


    An expert whose answer gotĀ voted for 2 times.

    Problem Solver:

    An expert who has answered 5 questions.

  • Contributor
  • 9 Answers

It is your Fan Clutch going. That thing causes all kinds of settings on the computer to readjust as it fails. The fortunate folks that I know that it happened to simply experience a sudden roar of the engine sound,, loss of compression, and just a wide assortment of symptoms. But it was the Fan Clutch. Part only cost about 125 bucks, but after it is installed, a computer download must be performed that is only available from the dearlership. 600 bucks. This should have been a recall item in my opinion,, but.

Posted on Dec 01, 2008


1 Suggested Answer

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

A 6ya expert can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
The service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
Good luck!

Posted on Jan 02, 2017


Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

Roaring engine noise in cab when idling. Idles at 500-950 rpm..When raising rpm in idle noise goes away.2002 GMC Envoy 6 cly.

Should idle between 500-600. Clean your throttle body with the battery disconnected to help with the fluctuation. The roaring very well could be your fan clutch. Fan clutches are a known problem with our platform. If engaged, will sound like an airplane.

Jun 06, 2017 | 2002 GMC Envoy

2 Answers

Starting point for firing order

Starting point is always cylinder 1, on straight engines at the front, on V engines front left. The gear wheel or crank sensor will register at TDC or just before. TDC can be found with a pencil inserted in the spark plug hole of cylinder 1
So for a 4 cylinder engine it's 1,3,4,2
6 cylinder straight, 1,3,5,6,4,2,
Cant remember the v engines but it's always left right etc.and from end to centre.

Apr 22, 2017 | GMC Cars & Trucks

1 Answer

I am a woman learning to fix my 2002 GMC Envoy and it is knocking and the oil disappeared. I had an oil change about 2 months ago.

Could need an engine rebuild you cannot drive without oil and not do damage to the bearings.

Mar 12, 2016 | 2002 GMC Envoy

1 Answer

GMC 2002 Envoy wont start

have the engine code read that will give you a new starting spot. without just throwing money at it.

May 27, 2012 | 2002 GMC Envoy

2 Answers

My 2002 Envoy engine shuts down in low, i notice a huge leak of dex cool in drive way, also when i turn of the air condition the rpm goes down and sound like ready to shut down. The rear its un level righ...

I don't see any need to go into a long story here

You have at least two problems that may not be
all that big a deal

I would flat bed it to a dealer or local repair shop

Sep 23, 2011 | 2002 GMC Envoy

1 Answer

Engine knocks cold ok hot

if its at the top end its pistion slap
if its at the bottem end(of your engine) its a crank shaft bearing.

with out going into extream detail,

a ting sound at the top is a pistion slap.... replace all your pistions posibly over hual the engine.

a dubble knock that gose with rpm but sounds 2 knocks very every fireing of the pistion is a crank bearing..... replace your crank shaft bearings.... all of them b/c metal gose threw an engine extreamly fast and will destroy other beraings. this knock on start up will turn into a knock all the time, then a very louad knock that will end your engines life.

unfortunetly the answer is engine rebuild and fast.

May 30, 2009 | 2003 GMC Envoy

1 Answer

Envoy is running on highway and suddently turn off & wont start

This could be a bad key. Expensive but if necassary to replace to check on the symptom of the car since no codes are being thrown. I would also say check your Idle Air Control valve and your EGR valve to make sure they are working proplery

Apr 17, 2009 | 2002 GMC Envoy

4 Answers

2002 GMC Envoy

If your 2002 gmc envoy or sierra will not even turn over with a kown good battery try starting it in nuetral then go back to park and try starting again. There is a park nuetral safety switch that can malfunction. Turn the key on then shift into nuetral, then turn fully to start.

May 19, 2008 | 2002 GMC Envoy

Not finding what you are looking for?
2002 GMC Envoy Logo

282 people viewed this question

Ask a Question

Usually answered in minutes!

Top GMC Experts


Level 3 Expert

78010 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22306 Answers

Ronny Bennett Sr.
Ronny Bennett Sr.

Level 3 Expert

6927 Answers

Are you a GMC Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides