Need help!!!

Discussion in 'General Automotive Tech' started by Grizz, May 12, 2018.

  1. Grizz

    Grizz Are we there yet???

    Joined:
    Mar 4, 2016
    Messages:
    1,307
    Likes Received:
    553
    Trophy Points:
    293
    Wagon Garage:
    2
    Location:
    Nashville, TN
    my friends mom has a 2002 Tahoe. 5.3 vortex. She couldn’t pass inspection because of the check engine light. My scanner showed p0178;p0179 codes. They relate to a flex fuel sensor. I unplugged this sensor to test voltage. When I plugged it back up and went to start the car i get nothing. It turns over all day but it’s not getting gas. I can’t here the fuel pump and get little coming out of the bleeder valve. Does anyone have a remedy??? I was just talking up Chevy and how they are so simple to work on and then I go eating my own words. She seemed ok with getting a ride home but I know this will bother me until it’s resolved. I’m confused on how unplugging a sensor could cause this much trouble. Also she had 3/4 tank and now the gas gauge reads zero. My first assumption is fuel pump assembly but I don’t know how the car could go from running to not, just by unplugged sensor
     
  2. Poison_Ivy

    Poison_Ivy The crazy kid in the sandbox

    Joined:
    May 20, 2017
    Messages:
    3,722
    Likes Received:
    826
    Trophy Points:
    356
    Location:
    Leaving the cake out in the rain
    I'm not sure how GM sets these up. But, if I were to disconnect the battery on my Audi, which I haven't had a reason to do yet, I'd have to type in a code, to get the hi-fi to play. What's true is that if I remove a stuffed up particle filter on a late model Diesel and then send it out to have baked, when I get it back and install it, connecting the sensors to the plugs, if the computer co-ordinates don't get set back, the computer will continue delivering fuel to what it still thinks is an engine with excessive back pressure.
    In your case, if it ran before and now does nothing, it has to be something that simple. What you need to do is to get hold of that plug-in device which resets everything, including that idiot light and fuel guage. They make everything interconnected, anymore.
    In my case, either a dealer will look up the radio code, if I were to loose it, and give it to me, free of charge, as customer service and there are other dealers who will only book you to have them type it in, footing the customer the bill
     
  3. Silvertwinkiehobo

    Silvertwinkiehobo "Nothing is foolproof as fools are ingenious."

    Joined:
    Apr 21, 2014
    Messages:
    7,988
    Likes Received:
    1,391
    Trophy Points:
    505
    Location:
    Everett, WA
    You need to re-disconnect the connector and ensure there's no corrosion, no heat damage, and 'snug up' the female terminals in the connecter shell, as it sounds like an open circuit, or the connector had not fully seated with a click and came back apart. The GM fuel modules do have a history of overheating which can burn the terminals or cause the female terminals to expand so much they barely hold, and undoing the connector really breaks that hold and they don't touch when you plug back in. PM me if you have any further questions, as I have extensive experience with these modules and their connectors.
     
  4. OldFox

    OldFox Curmudgeon

    Joined:
    Feb 20, 2013
    Messages:
    955
    Likes Received:
    154
    Trophy Points:
    115
    Location:
    West Tn
    Maybe someone stole the gas without you knowing it. We are having a rash of gasoline thefts in our neighborhood. As the price goes up, the thieves get bolder.
     
  5. Grizz

    Grizz Are we there yet???

    Joined:
    Mar 4, 2016
    Messages:
    1,307
    Likes Received:
    553
    Trophy Points:
    293
    Wagon Garage:
    2
    Location:
    Nashville, TN
    It’s a thought... but she was driving before I pulled the plug, so unless someone is playing a cruel and extremely clever trick...or she could be going senile?
     
  6. Grizz

    Grizz Are we there yet???

    Joined:
    Mar 4, 2016
    Messages:
    1,307
    Likes Received:
    553
    Trophy Points:
    293
    Wagon Garage:
    2
    Location:
    Nashville, TN
    Went back out today armed with new info. And diagrams. Thanks Andrew! This is what I found. I couldn’t really see so I used the phone camera to get in there and shoot some grainy pics of the prongs on the sensor itself. I like what I see!! Looks to me that one is missing. Do ya think that has anything to with anything? :idea: Going back out soon to pull the sensor and get a good look at it. I know your all on the edge of your seat so I’ll keep ya posted. Oh yeah, surprise surprise! It’s going to rain for the rest of the week:grumpy: 74B3116E-83CC-472C-A376-191E8578D4DC.jpeg B1EBF122-2382-42BD-AF0E-0335FFAD51F0.jpeg
     
  7. OldFox

    OldFox Curmudgeon

    Joined:
    Feb 20, 2013
    Messages:
    955
    Likes Received:
    154
    Trophy Points:
    115
    Location:
    West Tn
    Only if you can see the broken prong inside of the connector itself. Look there first. Maybe there isn't supposed to be a prong in that location.
     
  8. Grizz

    Grizz Are we there yet???

    Joined:
    Mar 4, 2016
    Messages:
    1,307
    Likes Received:
    553
    Trophy Points:
    293
    Wagon Garage:
    2
    Location:
    Nashville, TN
    No prong in the connector BUT there are three wires: pink, white, black. Black is ground (thanks Andrew!) White goes straight to the ecm, pink I’m not sure, but I’ve had her order the part which she got off amazon for $300. They had them at Oreilly for $500. I don’t trust the internet stores but That’s due to bad previous experiences. I like being able to carry wrong or faulty parts back to the same human that I bought them from. It’s a lot of money but I can’t think of anything else
     
    Last edited: May 15, 2018
  9. Krash Kadillak

    Krash Kadillak Well-Known Member

    Joined:
    Feb 14, 2008
    Messages:
    17,870
    Likes Received:
    759
    Trophy Points:
    558
    Wagon Garage:
    1
    Location:
    Springfield, Oregon
    I have no idea whether it will help, but it's worth a try, and doesn't cost anything. Try resetting the emergency fuel shut-off. procedure should be in the owner's manual.
     
  10. Grizz

    Grizz Are we there yet???

    Joined:
    Mar 4, 2016
    Messages:
    1,307
    Likes Received:
    553
    Trophy Points:
    293
    Wagon Garage:
    2
    Location:
    Nashville, TN
    Inertia switch? I don’t think it has one. I don’t think I’ve ever seen one on a Chevy
     
  11. Poison_Ivy

    Poison_Ivy The crazy kid in the sandbox

    Joined:
    May 20, 2017
    Messages:
    3,722
    Likes Received:
    826
    Trophy Points:
    356
    Location:
    Leaving the cake out in the rain
    Like Old Fox says, if the prong didn't corrode off and get stuck in the connector, there wasn't a prong in there, to begin with. I've got plenty of connectors which have missing teeth, because of common harnesses being shared between different models using different gadgets. GM doesen't rationalize any doifferent than does any other car maker, including mine. Is there a cable shoe, at the end of that 3rd homeless wire? If not, you should easily be able to pull that wire out
     
  12. Silvertwinkiehobo

    Silvertwinkiehobo "Nothing is foolproof as fools are ingenious."

    Joined:
    Apr 21, 2014
    Messages:
    7,988
    Likes Received:
    1,391
    Trophy Points:
    505
    Location:
    Everett, WA
    What likely happened is that the third pin had the barest of hold inside with the connector, but as soon as Grizz pulled it off to test, it fell out, and without it, the pump module wouldn't activate at KOEO or cranking. Of course, when you go to change this out, Nosmo King is in charge, and no drumming the tools on the frame or exhaust while the lines are undone.
     
  13. OldFox

    OldFox Curmudgeon

    Joined:
    Feb 20, 2013
    Messages:
    955
    Likes Received:
    154
    Trophy Points:
    115
    Location:
    West Tn
    Did you hear the "naming the baby" joke?
     
  14. Grizz

    Grizz Are we there yet???

    Joined:
    Mar 4, 2016
    Messages:
    1,307
    Likes Received:
    553
    Trophy Points:
    293
    Wagon Garage:
    2
    Location:
    Nashville, TN
    Good gracious, good heavens, and deary me! I had to google him. He’s before my time. Apparently he’s before anyone alive today’s time too? What is he supposed to be?!
     
  15. OldFox

    OldFox Curmudgeon

    Joined:
    Feb 20, 2013
    Messages:
    955
    Likes Received:
    154
    Trophy Points:
    115
    Location:
    West Tn
    It's an old dumb, 50 year old joke. A young couple just had a baby and couldn't decide what to name him. The wife decided on a doctor's name. Laying in bed, she looked out one door and saw Nosmo. Then she leaned over and looked out the other door and saw King. They decided these must be 2 good doctors, so they named the kid Nosmo King Smith. Once she was released and headed home, she saw a sign in the hallway that said No Smoking.
     

Share This Page