Back to bad MPG heat range causing it?

Discussion in 'Vortec 4.2L I-6' started by AzTruckGuy, Jul 11, 2016.

  1. AzTruckGuy

    AzTruckGuy Well-Known Member

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    Like clockwork
    IMG_2455.JPG

    And my 4x4 switch broke!!!!!

    IMG_2456.JPG
     
  2. Mooseman

    Mooseman Moderator

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    Hopefully that new sensor will take care of it. While you have the tank down, check the top of the fuel pump module for corrosion, especially on the vent line. Fuel lines regularly leak there due to corrosion perforation (been there) and could be possible that the vent line could have the same issue.
     
  3. AzTruckGuy

    AzTruckGuy Well-Known Member

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    I'm actually thinking of replacing the fuel pump, Ive been driving lately and the Trailblazer just feels sluggish. Hell if I have to take the tank down might as well just replace that also, my stall issue has not gone awa, it hasnt stalled on me but at times it feel like it is. I think that fuel pump is going out
     
  4. Mooseman

    Mooseman Moderator

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    Quite possible but this is a much bigger expense.
     
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  5. gmcman

    gmcman Well-Known Member

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    I would check the pressure nipple at the fuel filter for proper pressure first. If you have good pressure with engine off and with engine running, then I would look at the fuel pressure regulator. I mentioned this earlier, did you ever replace it?

    Far easier to check the pressures than to drop the tank.

    The FPR is one of those things you just can't really test, so the notion of throwing money at a problem doesn't really apply here, more of a preventative maintenance thing.
     
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  6. AzTruckGuy

    AzTruckGuy Well-Known Member

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    I ordered a FPR last week and its on the way and its not an Ac Delco it is an aftermarket unit to be used for testing only ...I did test the fuel pressure....Turned it on and it was fluttering in between 50 and 60, after this test one of my ignition coils went bad and had been going out for a while with no code..I replaced all of the coils

    97779_0f697b24cd55e7b828cf5fb690ed8b0f.jpg

    Fuel pump would be aftermarket and around $50 discounted due to being returned and not used...its fuel pump that is normally $175...

    I don't plan on having the Trailblazer in 2017...
     
  7. AzTruckGuy

    AzTruckGuy Well-Known Member

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    I got the FBR and Fuel Tank Pressure Sensor today...installed the FBR and its the same...Didn't get to install the FTPS...due to installing rear rotors and pads...I will have to get to it at some point over the weekend...I'm glad I didn't waste $50+ on the FBR.....starting to think I should deal with this?

    Also noticed my tank has a sensor above the filler tank hose area and looked up a diagram so do I have 2 fuel tank sensors?

    http://www.gmpartsdepartment.com/pa...iteid=214533&vehicleid=190205&diagram=GN02365
     
    Last edited: Sep 23, 2016
  8. Mooseman

    Mooseman Moderator

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    I think it's the same one. Just the way the diagram shows it. It's on the fuel pump module. It's the only one I've ever seen on the tank. The other is the fuel level sender of course inside the tank.
     
  9. AzTruckGuy

    AzTruckGuy Well-Known Member

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    **
    I just took this and I looked it up ...some are saying this is the pressure sensor?
    tANK.png

    ***Updated*** Hate to post the other site http://forums.trailvoy.com/showthread.php?t=79445 but its confirmed? they started putting on by the fuel pump on 2005+ models? Wow I have an easy job now, I think I will put this on now...
     
    Last edited: Sep 24, 2016
  10. AzTruckGuy

    AzTruckGuy Well-Known Member

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    I cant make this up even if I wanted too... FUEL TANK SENSOR.png

    Guess were the broken piece fell? Put the new one on and turned the power on but didn't start the vehicle for fear of that piece going throw the fuel system.....Still have those fails and now I have new fails on the Oxygen sensors side....
     
  11. Mooseman

    Mooseman Moderator

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    It shouldn't affect anything. The pump has a filter of sorts (a sock) so it won't go in there. It might jam up the fuel level sender but I'd say the chances are pretty slim.
     
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  12. AzTruckGuy

    AzTruckGuy Well-Known Member

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    That's good to know...Fuel Pump will be coming in on Monday...I'm stumped man the fuel sensor didn't work either....
     
  13. Texan

    Texan Well-Known Member

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    I assume that you have checked the evap. system purge valve.
    It is up front, drivers side, under the intake manifold.
     
  14. AzTruckGuy

    AzTruckGuy Well-Known Member

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    Front and rear changed out, charcoal canister hasn't been changed and it won't since every part I've replaced so far has been good not dropping $150 on it
     
  15. Mooseman

    Mooseman Moderator

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    Find a used one. Haven't heard of these failing a lot so might be worth a shot. Pick-a-part would be cheap.
     
  16. AzTruckGuy

    AzTruckGuy Well-Known Member

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    I'm talking to some guy whos parting out a Trailblazer he got for the engine...I'm going to get the upper filler hose and see how much he wants the charcoal canister as well I got my fuel pump today and you were right, if its anything like the stock fuel pump, these fuel pumps are tight to not any objects get into the fuel lines..

    Fuel pump.png

    Bottom is sealed tight not to allow any objects in
    Fuel Pump1.png

    Nice stock looking seal
    Fuel Pump2.png

    Don't really need to fish out the Fuel Pressure Sensor nipple that broke off as it wont do any damage, but I will anyways when I do drop the tank. I was going to do it today but than I saw our very own May03LT video on how much it sucked and time consuming. I have to drop off the Trailblazer early in the morning to get the struts/motor mounts put on, so I don't even want to start a job and not be able to drop off at the shop.

     
  17. AzTruckGuy

    AzTruckGuy Well-Known Member

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    Just got some photos of the used parts from the seller


    His hose seems to have more ridges than mine?
    filler hose.png

    My hose
    My hose.png
    My hose1.png

    His Charcoal canister

    charcoal.png
     
  18. AzTruckGuy

    AzTruckGuy Well-Known Member

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    I did the fuel pump yesterday and it took me about 6hrs to do it, due to the straps being difficult and the stupid position of the charcoal can tabs, I ended up breaking the 2 plastic retainers and the one from the rear purge, so I called the dealer and these stupid a$$ retainers are $7 a piece? Here's my take on the evp hoses since I am driving around without 3 retaining pins, this evp system is a mess. Chevy did a piss poor job on it and like I am experiencing, I have replaced parts that didn't need to be replaced because how this Evp system is. Fuel Pump has not fixed my P0440 issue and it will pop up again. Trailblazer is stressing the sh$t out of me and also annoying me..

    Here's the old Bosch fuel pump
    IMG_2604.JPG

    I looked at connections and hoses to the fuel tank and they looked fine, I didn't see any issues or rust issues that others have experienced. I fished out the broken pressure sensor tip that broke off and I reused the gasket that that was on the old Bosch unit as the gasket was longer than the one that came with the new fuel pump. I started it up last night and everything was fine and the gas gauge seemed to be reading correctly, seemed to indicate a true reading vs the Bosch unit. Well that's not how this Trailblazer works does it, this morning I have the dreaded empty fuel warning light and first thinking it was empty, I put about $10 worth of gas to get the needle moving up, of course it doesn't and now it just that. I'll have to look at the video that May03LT did again, because I think he experienced the same thing. I can not tell how annoyed I am, especially since I am moving to Phoenix tomorrow and I wont be able to work on this damn Trailblazer anymore up there.
     
    Last edited: Sep 30, 2016
  19. AzTruckGuy

    AzTruckGuy Well-Known Member

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    Damn it just gets better while driving, the SES light came on and also reduced engine power light came on, pulled over and turned it off and turned it back on again. Have an appointment with the dealer to do a alignment after the suspension work was completed....

    Update so checked the OBD scan and it's coming up with a P1271 code WTF? Motor mounts were changed by someone on Tuesday
     
    Last edited: Sep 30, 2016
  20. Mooseman

    Mooseman Moderator

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    It may be the fan clutch as it was documented in the past of messing with the 5V reference line. Unplug it and see if it goes away. Yes, you can drive it with the fan disconnected but will get a code for it. Just keep an eye on the temps and don't use the A/C if you can.
     
  21. AzTruckGuy

    AzTruckGuy Well-Known Member

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    I had the Ac in when it happened. But I just got home and lifted the side with charcoal canister and messed with the hoses and now the SES light is gone. I don't have retaining clips in both since they broke off, the lower hose seems more prone to come off than the top. I'm running without 3 clips at the moment, I wonder if the hoses not being tight is causing this?

    Update just ran it with the bottom evp hose off the charcoal canister and it didn't even push a code or sputter it just ran, turned it off and put the hose back on and the same no code or sputter. What am I supposed to do with this stupid fuel warning light on? How do I fix that?

    I don't trust this effin Trailblazer to drive me up to Phoenix and not cause some BS issues, I'm never had a vehicle where you fix things and it just gets worse. Just rented a car to take care of my lease on Saturday, I'm going to have to come back and fix it since I found the clips up in Phoenix $6.50 a piece for these stupid clips
     
    Last edited: Sep 30, 2016
  22. MAY03LT

    MAY03LT Moderator

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    Those stupid canister clips break all the time, a ziptie is a great substitute. It's hard to describe how to situate it so the evap line stays on but it sounds like you have some technical skills so it shouldn't be too hard to figure out.

    For the fuel sender I would try to get to the fuel pump connector and ohm out the sender. I know it sucks but the odds are more toward a problem with the sender then a wiring issue.

    Just out of curiosity can your scan tool read fuel tank pressure sensor voltage?
     
  23. AzTruckGuy

    AzTruckGuy Well-Known Member

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    The IPhone version of Torque has GM setting for tank pressure but I can't get it to come up. I also just put in a new tank pressure sensor, I have zip ties I thought of that too but I just don't trust this Trailblazer at all with this fuel pump put in, I just cant believe this sh!t. When I move up to Phoenix I am going to have to drive 52miles a day to work and home. I regret even pulling the fuel pump, everybody wants to $299+ for the Bosch unit here and they don't even have it in stock.

    I drove to the autostore a couple of blocks away and the codes came back...driving back the SES light was still on and the REP was gone....Let it cool down and no codes....Sorry but this is just so effin stupid...I feel like putting the old Bosch unit back in
     
    Last edited: Sep 30, 2016
  24. MAY03LT

    MAY03LT Moderator

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    I was in the same boat and got mine from amazon. There's a 67415 (fits 02-04) on amazon right now for under $160/shipped. Advanced wanted over 3 bills. Also worth noting, I've been having such good luck with delphi pumps that I'm going to use theirs for my wifes Tahoe.

    Are the codes you're getting now just p0440 and p1271?
     
  25. AzTruckGuy

    AzTruckGuy Well-Known Member

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    Thanks guys for the help, I am just so effin frustrated. I have to go up to Phoenix tomorrow in a rental to give the realtor the deposits for my new place and I start my new job on Monday. So this is just too much..

    May03LT I had that fuel pump in my cart but they wouldn't be able to deliver it till Monday. I ordered it anyways, forget Dephi for me they want $369+ everywhere here. Those auto stores are complete crooks

    Ok here's the original code that popped up
    p1271.png
    That load value is high with the new fuel pump

    I cleared it out and no codes
    Codes.png

    These codes are related to my P0440 codes and whatever I do they just wont effin go away

    PO440 codes.png

    P0440.png


    Since buying new parts and replacing suspect parts for the P0440 I now have the oxygen sensor test failing and they have both been replaced
    oxygen sensor.png

    And now for the kicker with a new fuel pump look at that short term fuel % that sh!ts not right
    Short term Fuel.png

    So what I have learned new parts are bad it fails tests.

    I'm going to have to rent a rental for a week and come back to do this fuel pump install again with the Bosch unit. I wonder if I should order a new gasket? I reused the old one since it had a long range area than the new gasket. My ring was fine minor rust, I was able to take it off with ease and install it with ease as well
     
    Last edited: Sep 30, 2016
  26. Mooseman

    Mooseman Moderator

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    The new pump should come with a new gasket. I don't know what brand pump you bought the first time but I suspect it was some unknown brand, likely made in China. The Bosch should be fine.

    The clips for the lines are available from Dorman a lot cheaper. I found them in the Help! section in the parts store. But for these lines, which don't carry actual fuel, you can get away with the zip ties. 4 small ties would probably do the trick. One around loosely the line, one loosely around the other end, two looped around the other two, tighten the first ones and then tighten last ones.

    As far as your frustrations go, all I can say is that I have been there before myself when I first got my TB. All it needed was an engine. Yeah right! Seemed it was just one thing after another. Eventually, I got it done and it has been a reliable truck since. You're under the gun to get this fixed, with a move and new job on top of that, of course all you're gonna feel is frustration and stress. Take care of everything else and then get 'er done after everything else is settled down.
     
  27. AzTruckGuy

    AzTruckGuy Well-Known Member

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    The Fuel Pump I got was a spectrum premium and this link says I got a fuel pump for an extended model????
    http://ecat.spectrapremium.com/a/3132 When I compared them they have different PSIs but the same ohms? Stupid Amazon said this pump fit my short wheel base. Doesn't matter Bosch unit is coming in on Monday. The kicker is the same Spectrum fuel pump here is $299+tax

    3 clips will be sent by the person I bought a charcoal canister & upper filler tank piece from his trouble free running Trailblazer. This the last of the evp pieces to replace, if this doesn't clear the P0440 code, I'm done with the EVP system.

    I'm starting to suspect I have a bad cat, seems the evp pieces are being fixed and now issues are coming from the Oxygen sensor areas, since the thermostat was bad for unknown amount of time and my sister prob ran it like that...it could be failing and not throwing a code. If it is the cat, it's going to have to wait a month or 2 just don't have the funds after throwing $1500+ into it the past couple of months
     
    Last edited: Oct 2, 2016
  28. Mooseman

    Mooseman Moderator

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    The EXT has a bigger tank and probably a different shape so the pump module is different than the SWB, which could explain the problems with the fuel level sender. Anyway, you'll be able to return that other pump to Amazon as the wrong part.
     
  29. AzTruckGuy

    AzTruckGuy Well-Known Member

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    Paying someone to install the fuel pump tomorrow for $100, wont have time to install when I head back on Saturday and would rather have it installed and see hows it running before I make a 165 mile trip to Phoenix with it. Should I install a new fuel filter? Even though I just got one like 8 months ago? The gas looked pretty clean in the tank when I dropped the tank before
     
  30. Mooseman

    Mooseman Moderator

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    The filter should be OK. After the pump is replaced, you should be good to go, even if it might still get a P0440. It won't affect driveability.
     
  31. AzTruckGuy

    AzTruckGuy Well-Known Member

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    The guy replaced the fuel pump in under an hour, parents have been driving around in it and say its so smooth, should be front struts and motor mounts were replaced too. I told them to keep driving it till I get there on Saturday. I have been driving so much up in Phoenix, I want to get that P0440 code fixed, so I can at least get the MPG up.
     
    Last edited: Oct 6, 2016
  32. AzTruckGuy

    AzTruckGuy Well-Known Member

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    Well look what I got up in Phoenix, the filler gas hose already looks much better than my 13 year old hose. Let's hope this solves the P0440 issues
    IMG_2668.JPG
     
  33. AzTruckGuy

    AzTruckGuy Well-Known Member

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    I cant wait to be done with this BS....The fuel pump is running great and I got an alignment that was much needed on the Trailblazer...It was way out of specs....

    Unsure how a screw went missing on my fuel neck filler...but got the screws from the 2007 fuel neck filler I bought for the hose(cant use the fuel filler neck due to a different design than my 2003
    Fuel neck.JPG

    My hose didn't seem to have any holes but the 2007 model just looks better
    Hoses.JPG

    You would think these charcoal canisters are the same right? They have the same part # and are made by Delphi....Its never that easy

    Canisters.JPG

    My original canister middle port is thinner

    orignal.JPG

    and the 2007 model middle port is thicker

    newer.JPG
    I wanna effin shoot myself at this moment with this damn part....
     
  34. AzTruckGuy

    AzTruckGuy Well-Known Member

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    IMG_2683.JPG So this 90° connection didn't fit the new charcoal canister I had to improvise

    Bought this straight line at Napa $20
    IMG_2684.JPG

    Yes because it's not 90°s the plastic line was bent so instead of putting the charcoal canister it its tabs I moved it forward away from the tank, so the line wouldn't bend so much. The way GM positioned this canister it won't fall out, even if I left it loose due to the Evp fittings acting as holders for the charcoal canister.

    Unsure if maybe the fuel pump or combination of the upper fuller tank hose and charcoal canister fixed my mode 6 issues but they are passing on the OBD fusion app. One thing I did notice on my old canister is I could hear the canister particles loose when I shook it vs no sound from the newer charcoal canister.

    This still leaves me with a mode 5 issue now which pertains to the oxygen sensors, which leads me to think that my cat is failing or it has failed . It feels sluggish on acceleration.
    IMG_2685.PNG
     
    Last edited: Oct 9, 2016
  35. AzTruckGuy

    AzTruckGuy Well-Known Member

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    So I just made the trip in the Trailblazer up to Phoenix, it performed amazing. Man for all my complaining I have done on this post, I take back any negative things I said about this Trailblazer, once they are ready to go and taking care of, they will treat you right. Even the gas was at level on level with all the 2016 shiny rentals I have been renting this month and the last year. Half a tank left vs using the full tank when I drove the Trailblazer to Phoenix about 8 months ago

    IMG_2691.PNG

    Unsure if it was getting 27MPG as the ELM keep disconnecting, but I would say it was up there.

    Ok so the thing I noticed that leads me to believe I do have a bad cat is while driving I hit a mini hill and the Trailblazer got sluggish and I just pushed the gas to make it go fast and it did, but it was slow at first. Smelled a sulfer smell in the cabin after I did this.

    When passing other vehicles and I was hitting around 95, it was also sluggish and I floored it, and that sulfer smell hit the cabin again.

    So what do you guy think? Cat?
     
  36. Mooseman

    Mooseman Moderator

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    Sure sounds like it. A back pressure test would confirm it for sure but I had the same issue with mine and the cat was plugged.

    That mileage is calculated by the PCM and can be deceiving. Only real MPG is by calculating manually or using Fuelly.
     
  37. AzTruckGuy

    AzTruckGuy Well-Known Member

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    I had the back pressure test done and it was showing fine, but I didn't trust that it just didn't feel right. Just like my one bad coil that wasn't giving me a code.

    https://www.amazon.com/gp/product/B0058PC6SG/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1 So I found this for under $50? What do you guys think? Its the whole unit as the size indicates. Even the Magnaflow website is showing the full unit http://www.magnaflow.com/products?partnumber=23967 I ordered it!
     
  38. Mooseman

    Mooseman Moderator

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    $50 is a heck of a deal for a Magnaflow. Sure worth a shot and can't hurt for sure.

    Backpressure test depends on how it was run. If just at idle, then yeah, it might not show enough. Even 2-3000RPM might not be that bad. With all the misfires and stuff, it probably is partially clogged. I was able to see mine as partially clogged, about 1/3.
     
  39. AzTruckGuy

    AzTruckGuy Well-Known Member

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    So my SES light come on again this morning and I am ok with as it has been narrowed down to one area now in the mode 6 system

    ID50.PNG

    So I looked up this code and this what I got from this article

    http://www.justanswer.com/gm/7nzyd-gm-envoy-familiar-mode-diagnostics-information-i.html

    TID: $02 CID: $50 is "EVAP weak vacuum pass test 1"

    GM shows for parameters -32.768 to +3276.7 in of H20 Vacuum to pass.

    So my fittings are not connected by the plastic retainers since I broke them taking off charcoal canister and rear solenoid purge valve, I just connected and let them be. Do you think this is the cause or could there be something else? Man I am almost there with this P0440 code being diagnosed.
     
  40. AzTruckGuy

    AzTruckGuy Well-Known Member

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    Just crossed the 100,002 range and with the SES light on. I hate that light

    Odo.JPG
     

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