Question about GMC Sierra 1500

1 Answer

I have a 2002 GMC 4x4 Sierra 1500 5.3L - After starting in the mornings, the engine revs up and then idles very low almost to the point of dying sounding very rough. Runs fine after it warms up. I have replaced the air filter and mass air flow sensor, fuel pump and filter, fuel pressure regulator, plugs and plug wires. Seemed a little better after replacing the fuel pressure regulator. Some say to replace the IAC or the air intake gasket. All codes say misfire.

Posted by on

  • tedge1988 Feb 09, 2010

    Check engine light is on. It only revs up high after starting in the mornings. It went off for 2 days and came back on flashing while in the car wash.

  • tedge1988 Feb 10, 2010

    The codes are PO171, PO174 and PO300.

×

1 Answer

  • Level 2:

    An expert who has achieved level 2 by getting 100 points

    MVP:

    An expert that got 5 achievements.

    Mentor:

    An expert who has written 3 tips or uploaded 2 video tips.

    Governor:

    An expert whose answer got voted for 20 times.

  • Expert
  • 146 Answers

Is the check engine light on? Does it only rev one then go low or keep reving up and down? Thanks

Posted on Feb 08, 2010

  • edwin187 Feb 09, 2010

    Ok, bring the vehicle to your local parts store and have them connect a scantool to check the diagnostic codes and let me know what codes your getting. Thanks

×

1 Suggested Answer

6ya6ya
  • 2 Answers

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

Hi,
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.
goodluck!

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%

my-video-file.mp4

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

×

Loading...
Loading...

Related Questions:

1 Answer

My 1990 GMC Sierra 4x4 wont shift into overdrive the engine just revs up after second gear. All the other gears work fine.


check the wires on the overdrive solenoid on top of the gearbox .if ok change the overdrive relay.

Dec 21, 2013 | Cars & Trucks

1 Answer

1995 GMC with 350 engine auto transmission idle to fast. Have replaced oxygen sensor, idle air control, and throttle potion value. can see butterfly values are closed when the engine is running at an...


It sounds like you have a vacuum leak somewhere. Take a propane torch, turn on the gas but DON'T LIGHT IT!!! Start the vehicle and point the torch at any and all vacuum outlets and hoses. If the engine revs up slightly, you have found your leak. The vacuum will pull the propane into the engine causing it to rev. Check the throttle body mounting plate good and vacuum lines at the back of the engine and transmission. Hope this helps.

Apr 03, 2011 | 1995 GMC Sierra C1500

1 Answer

The truck will start with jumper cables and idles very slow and then dies it is a 2002 gmc 1500 4x4.


your entire electrical system requires a minimum of 12.6 volts to operate correctly - if you don't have enough voltage then the system can react very unpredictably - check the voltage across the battery - if it is not 12.6 volts then charge or replace the battery to get the correct voltage - then start the vehicle and the voltage should increase to 13.5 to 15 volts - if the voltage does not increase, then the alternator is not charging and will need to have the electrical system serviced or the alternator replaced - good luck with your repairs

Feb 14, 2011 | 2002 GMC Sierra

1 Answer

2002 gmc tranny slow to go in rev only when cold(-10) when oil warm no trouble, but on cold mornings can take 30 sec or more,but ok when oil warm-been this way for a few years


Is your fluid level low? Does it have a burnt smell - clutches burnt. Your trns filter may need changing and the oil replaced.

Nov 17, 2010 | 2002 GMC Sierra

1 Answer

Went to start my truck Sun morning and it idled very sluggishly. When it was given the gas it hesitated. Applied brakes and it died but started right up. No warning hadn't driven it for a couple of days,...


I own a 93 GMC and I have had this happen a few times, First its a chevy they are cold blooded take a bit to warm up and get heat. That and im sure the oil had not warmed up and gotten up to the top end. Let it warm up then try it out.

Nov 02, 2009 | 1993 GMC Sierra K1500

1 Answer

Won't start after battery died and recharged


Sounds like low voltage.
Get a boost from another car with a good set of cables.
Once started check voltage with booster car disconnected.
Is it around 14 volts?
If so,the truck is charging, so it may be time for a new battery.

If the voltage is at 12 or lower while running the truck is not charging.
May be time for a new alternator.

The battery should have charged enough in 1 hour to start the truck.
You may need a battery and alternator.

Sep 07, 2009 | 2002 GMC Sierra

1 Answer

2002 gmc sierra, 3500, 8.1, flashing mil, dies, starts rough idle



First buy the alldata subscription for your unit and read the engine power management system, once you understand this then you will see you don't need a scanner, you can code out if it's a engine problem then read the codes itself with a paper clip. Then once you get the codes post them here to get a better answer, the more information you can provide the better the answer you will get. A digital test meter will be better than a scanner. Without understanding the engine management system you won't be able to fix it without replacing a lot of parts.

Aug 02, 2009 | GMC Sierra 3500 Cars & Trucks

Not finding what you are looking for?
Cars & Trucks Logo

Related Topics:

63 people viewed this question

Ask a Question

Usually answered in minutes!

Top GMC Experts

yadayada
yadayada

Level 3 Expert

75197 Answers

Freddy

Level 3 Expert

1311 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22095 Answers

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

Answer questions

Manuals & User Guides

Loading...