Mechanical help needed

Discussion in 'Lounge' started by tallbump, Mar 15, 2015.

  1. tallbump

    tallbump Supporting Member

    Ok car people...chasing down an electrical/sensor issue on the 05 Chevy Equinox. When you start it, the Check Engine Light Comes on, along with the Reduced Power Light and the Traction Control Light. When this happens, you can floor it and the RPMs won't go over 2200 and the car won't go or go VERY slowly.
    If you let it sit for a while, sometimes 10 minutes, sometimes hours, the Reduced Power and TC lights will go off and it will drive fine.
    I had Auto Zone pull the codes and was told it was an P2138, APP (Accelerator Pedal Position) Sensor.
    We took it to the mechanic but the battery died while he was working on it. When he charged the battery, all the lights were off. He drove it several times and it never acted up.
    It drove fine for about a month....until yesterday. Happened again. We limped it to Auto Zone. Had the battery tested since it had died once...bad battery. Replaced the battery. The TC and Reduced Power went away, the CEL stayed on. Had them pull the codes. Car drove home fine. Rand it to the store and back last evening, all was fine but the CEL was still on.
    This morning, all lights were back on and it wouldn't go.
    Got the APP sensonr, got it installed (what a pain by the way), nothing. No change.
    Thinking, since the codes are for several different sensors, maybe something with the computer or the connection to the computer???
    Here are all the codes
    P0700 Transmission Control System Malfunction
    P1791 Transmission Control Module Loop
    P1125 Accelerator Pedal Position (APP) System
    P2135 Throttle/Pedal Position Sensor
    P2138 Accelerator Pedal Position Sensor Circuit Range/Performance
  2. MaryB

    MaryB Supporting Member

    Check the gas cap, seriously! Clean the throttle body also...

  3. Rachgier

    Rachgier Administrator Staff Member

    Had that same problem on my Suburban with the 4L60E. Turned out I had a bad injector and needed to replace the Throttle Position Sensor (TPS).
  4. lsi1

    lsi1 Member

    i'd like to see or hear some voltage numbers from the battery while its still in the car. I wonder if the alternator is not providing enough charge to completely maintain the battery at the correct voltage but still giving it enough to allow it to run the car.

    Sounds strange i know but i had an 03 taurus with a electrical charging problem that ended up being the serpentine belt tensioner pulley. it was providing enough tension to spin everything accept the alternator.
  5. lsi1

    lsi1 Member

    to elaborate when the battery was brand new and or the old battery was freshly charged from an external source it was working properly.
  6. Rachgier

    Rachgier Administrator Staff Member

    Oh yeah, the Traction Control Sensor issue showed up in my '99 Venture. Was a wheel bearing going bad which fouled out the ABS sensor. New hub assembly fixed that problem.
  7. I had that exact problem with an 2011 equinox we used to own. It was the throttle body. 4 bolts and $80

    Spent more money and time at the dealer trying to get it covered by the warranty to no avail
  8. tallbump

    tallbump Supporting Member

    Ok, apparently it doesn't have a TPS. Eliminated that possibility.
    It's also throwing two "C" codes.
    C0236 Missing Rear Speed Sensor Signal
    C0240 Camshaft Position Sensor 'A' Circuit Malfunction

    I can do a whole new throttle body, but that's a whopping $180 :mad:

    I do live just a few blocks from an Auto Zone. If it is running, i can get it there and have them check the alternator
  9. ajole

    ajole Supporting Member

    NE Utah
    I have the '06 Envoy. Intermittent CEL and "Service Stabilitrac" warnings, intermittent (rare) hard shifts into 2nd; and the codes say it's the transmission and/or Transfer communication modules.

    What I read on the 'net says it's common, there's about 10 possible fixes, none are certain, dealers can't isolate or fix for certain, and GM is ignoring it all.

    Here's what I want...make a car with a manual 6 speed tranny, no electronics beyond cruise control, heater/AC, and a sound system, mechanical injectors, no drive by wire, no 8 levels of engine management, no sensors, no camera, no electric windows, and then since we've left out $20K worth of tech, charge me about $10k for a new one.:D
  10. ajole

    ajole Supporting Member

    NE Utah
    That one sounds really bad.

    I had a Dodge, bad crank position sensor, the engine would just DIE! Wait a few seconds, or ten minutes...started right up and ran again, for days, or minutes.

    If the system doesn't know where the cam is, it can't decide what to do, that should put the engine in total chaos.
  11. cicpup

    cicpup Resident PITA Supporting Member

    Slow down. We need some creature comforts. Next you'll be eliminating cup holders.
  12. MXGreg

    MXGreg Supporting Member

    Government Motors....'nuff said.
  13. MXGreg

    MXGreg Supporting Member

    Sorry, that wasn't very nice of me.

    Electrical problems will drive you nuts. Been there, done that. You'll end up spending hundreds of dollars to find out it was a $20 sensor that was bad.

    I wish I could help you out, but I drive Fords.
  14. RedRaptor22

    RedRaptor22 Member

    I was a ford certified technician for a few years back from 02-06...all I worked on was brand new or newish cars, none of the 12 techs drove fords, they are no more reliable than anything else.

    And fwiw they also took a bail out just as large as chevy and dodge, of course it was after everyone was distracted by the others taking bailouts, and they simply called it a retooling loan.
  15. MXGreg

    MXGreg Supporting Member

    Don't get me wrong, I'm not saying Fords are better, was just poking a little fun. I've owned close to 100 cars in my life, I've seen good ones and bad ones from all the manufacturers. Today's cars suck to work on. Too many electronics all intertwined. One thing goes bad and it throws six other things out. Makes me love my '68 Merc that much more.
  16. rickm

    rickm Member

    They build cars now days to last 2 to 3 years then things start going bad and cost so much to fix that you will unload them and buy another one, just like evrything else built now days it is all throw away cause not worth fixing.
  17. dirt_19

    dirt_19 Supporting Member

    To be frank with that many codes I would be inclined to start checking electrical grounds . Poor grounds will cause sensor reading to be erratic and they can cause the charging system to preform poorly . I recommend finding a skilled mechanic well versed in finding electrical problems . Modern cars tend to have 20 or more grounds .

    The system does have a TPS but since the it uses a throttle by-wire system the tps is mounted the Throttle pedal here is a link to a few available on rock auto .
  18. Goodwrench13

    Goodwrench13 Member

    Ok iv been working on cars for years. Iv read thru this hole thing and most are right check your grounds add a couple if you want it will not hurt. If it was my car id add two. one from the battery to the frame and one engine to the battery. The other thing I have to ask is was the part you installed adjustable. Meaning were the bolt holes slotted if so it has to be set to a certain ohm value hence the slotted bolt holes. If not set right the (PCM) powertrain control module will read it as still bad. So there's my two cents hope you get it worked out
  19. Blue

    Blue Member

    Don't replace the throttle body, but do clean the Mass Air Sensor, you just take off the air intake and then can remove it.
    A can of MAS cleaner, (it is a delicate screen) spray it a bunch and let dry.
    While its off, spray into the throttle body and wipe it clean too.

    It cannot hurt, and might help.
    I had a car dying without throwing codes, and no lights, I changed the plugs and wires and the problem went away. That was after a mechanic had it for 2 days but could not find the problem as he was looking for codes to be thrown.
  20. HP/C9/45ACP

    HP/C9/45ACP Member

    I suggest going to a Chevy forum and finding a sub topic on the Equinox. Post your codes there, someone will probably offer suggestions on things to check and may be able to provide testing procedures. I'm also a Ford man. I do all my own work and haven't had any of my Fords to a mechanic for probably close to 15 years, but I know absolutely nothing about newer Chevy's. Also doing online research for solutions to these code numbers might turn up some testing procedures.