Edmunds Answers

Answers

  • zaken1 06/05/10 5:59 pm PST

    Instead of spending big bucks paying dealership prices; take the truck to a qualified independent repair shop (which preferably has ASE certified mechanics), and ask them to replace the fuel and air filters, and clean the fuel injection throttle body, the idle air control valve, and the mass airflow sensor. If the spark plugs have not been changed in the last 30,000 miles; I would also have them install new plugs. If those filters, sensors or spark plugs are dirty; it will put a lot of carbon out the exhaust; which will foul up the oxygen sensor.

  • warren99 06/05/10 7:24 pm PST

    Zaken1
    Thanks for your answer ! I think that the throddle body and mass air flow sensor sounds like a good answer as the problem is not the 02 sensor but it is a symptom. Is there a good way for me to do the work my self to help save bucks? Without a full blown shop! I am mechaicaly inclined do most of my own work, oil changes, brakes and other lower level jobs. Its not that I don't trust people, its just that I would rather do it myself to know what was done and how it was done. Again thanks!
    Warren99

  • zaken1 06/05/10 8:13 pm PST

    I'll be glad to help you to do this work yourself; but in exchange I ask that you trust my experience and do ALL the things I suggested, rather than only doing what seems likely to you to be the cause of the problem. Believe me; every one of those things could cause it, and sometimes it is caused by combinations of factors, rather than there being just one cause.

    There are two different chemicals need to do this job properly. One is called throttle body cleaner, and the other is called mass airflow sensor cleaner. The mass airflow sensor can be damaged by using anything except mass airflow sensor cleaner on it.

    The mass airflow sensor is located in the air duct from the air filter housing to the throttle body. Here's a link to a photo:
    (http://cardone.com/English/club/members
    /...
    ). Disconnect the hose from the sensor, and spray the inside of the sensor bore with mass airflow sensor cleaner until the sensor wires are clean and shiny. Do not touch or scrape the sensor wires with anything. Just spray them.

    The idle air control valve is mounted on the throttle body (http://www.rockauto.com/catalog/moreinf
    o...
    ) with two bolts and has an electrical plug connected to it. Remove the bolts and take the valve off. Spray throttle body cleaner into the opening where the valve attaches, and clean the metal tip of the valve.

    Disconnect the air duct hose from the throttle body, and spray throttle body cleaner all over the throttle butterfly and into every opening and passage. Take particular care to clean both sides of the throttle butterfly, and to remove all deposits from the bore near where the edges of the butterfly touch.

    If you decide to replace the spark plugs, and would like a recommendation about brand and model; please post the engine model (or the 8th digit of the VIN) and I'll reply with a plug recommendation.

  • warren99 06/05/10 10:19 pm PST

    Zaken1
    This is great, just what I needed! Many THANKS! I have enough experance to do this and I will work on this as soon as possible. I should have told you that I replaced the spark plugs two months ago, I bought Bosch platimum "2 "s ( double anode ) and they have performed great. The truck gets driven mostly around town and still gets around 18.5 mpg. I want to thank you again for your help. I am an electronic eng. and if I can help you with any electronic problem, just let me know
    Warren99

  • morin2 06/08/10 12:07 am PST

    Everyone who owns one of these trucks (not just the 99 MY) should print out Zaken's post and put it in the glove box for reference. I had one of these trucks and it was very good to me but also needed this same treatment. It can get so bad that the gas pedal needs a kick! The poor quality fuel we have now probably doesn't help at all.

    Warren, you're new here so FYI, when you're happy with advice, please leave a "thumbs up" for the poster - it shows your appreciation.

  • zaken1 06/27/10 2:19 pm PST

    Warren, I saw your note of appreciation, which I was able to read; but which I expect will soon be deleted, because it was posted in violation of the forum rule that ANY responses which pertain to a particular thread cannot be posted as a new question, and can only be posted in the original thread. I have no say in the rules here; all I can do is to tell people about them so their posts don't get deleted. There is one other way you can show your appreciation for my advice; and that is to log on, go to the question, and select my response you like best as "best answer." That will give me points, and will also close the question. Even after a question has been closed; it will still be possible to post additional responses to it. Thank you.

ADVERTISEMENT

Top GMC C/K 1500 Series Experts View More

Rank Leader Points
1. karjunkie 135
2. MrShift@Edmunds 85
3. laltazan 50
4. zaken1 45
5. snoofy 35
ADVERTISEMENT