2007 Chevrolet Trailblazer 4.2 Logo
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Anonymous Posted on Feb 29, 2012

P0506, P0411, P0171

My 2007 Trailblazer engine light came on a while back. I took it to get code and was told it was P0506. The next day, the battery on the truck died and I replaced it. That, of course, reset the engine light but it came back a couple days later, so I took it in to the dealer and was told that I had 2 codes, P0506 and P0411. They told me the air check valve needed to be replaced and the throttle body needed to be cleaned. They wanted to charge me $730 on top of their "diagnostics fee" so I told them forget it. I cleaned the throttle body and ordered a new valve and installed it. Engine light went out but came back shortly after. By this time, I have purchased my own scan tool, so I plug it in and get a P0171 code and the EVAP monitor did not complete. Here is what has been done so far: Checked vacuum hoses, there are no visible cracks. Cleaned MAF sensor Changed air filter Used techron in gas tank to help clean out fuel system In the meantime, I also had to replace the fan clutch and since it was such a headache trying to get that stupid bolt off (the "special" tool DID NOT work), the water pump was replaced as well. I have unplugged the battery to reset the computer but the code just comes back again and again. The truck will run fine for a day or two and then suddenly, while stopped, the rpm's will go down, then up, then down, then up and then the truck will run fine again but the engine light will come on with P0171 and the EVAP system monitor is incomplete. No other codes ever come up and all of the other monitors complete fine. The rpm bounce will happen once per drive cycle, after the truck is warmed up and has been driven about 8-10 miles. Before I bite the bullet and take the thing in to a mechanic and have to pay the labor costs, does anyone have any other suggestions? (My current mileage is 55,300)

1 Answer

raj somaiya

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  • Chevrolet Master 5,370 Answers
  • Posted on Feb 29, 2012
raj somaiya
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For OBD code problems check the list of help links below. Click the link below to go through its procedure.

--------------
Diagnostic Code P2195? http://schematicsdiagram.blogspot.in/2012/02/diagnostic-code-p2195-on-toyota-avalon.html

--------------
Diagnostic code P1330? http://technoanswers.blogspot.in/2012/02/diagnostic-code-p1330-on-kia-2wd.html

------------
Diagnostic code P0700, P1330, P1121? http://technoanswers.blogspot.in/2012/02/diagnostic-code-p0700-p1330-p1121-on.html

-------------
shows error code P1330? http://technoanswers.blogspot.in/2012/02/2003-kia-sorento-shows-error-code-p1330.html

--------
OBD code P1330? http://technoanswers.blogspot.in/2012/02/obd-code-p1330-on-2003-kia-sorento.html

------------
OBD code P01300? http://technoanswers.blogspot.in/2012/02/obd-code-p01300-on-toyota-rav4.html

--------------
OBD code P0768? http://repairhelpcenter.blogspot.com/2012/01/obd-code-p0768.html

------------
Evaporative Emissions System codes details? http://schematicsdiagram.blogspot.com/2011/11/evaporative-emissions-system-codes.html --------------- Engine Misfire codes?

http://schematicsdiagram.blogspot.com/2011/12/engine-misfire-codes-on-chevrolet.html

----------------


Misfire on cylinder 4?

http://schematicsdiagram.blogspot.com/2011/12/misfire-on-cylinder-4.html

--------------
ABS trouble codes for all models?

http://repairhelpcenter.blogspot.com/2011/11/abs-trouble-codes-for-all-1994-00-acura.html

------------
Diagnostic code P0010? http://schematicsdiagram.blogspot.com/2011/12/diagnostic-code-p0010.html

-------------
Diagnostic Code P1396?

http://howtobyme.blogspot.com/2011/11/diagnostic-code-p1396.html

--------------
Code P0452?

http://howtobyme.blogspot.com/2011/11/code-p0452.html

-------------


OBD code P0172 on Buick?

http://howtobyme.blogspot.com/2011/11/obd-code-p0172-on-buick-park-avenue.html

-------------
DTC Code P0321?

http://howtobyme.blogspot.com/2011/11/dtc-code-p0321-on-buick-park-avenue.html

------------------


Error Code P0471?

http://howtobyme.blogspot.com/2011/11/error-code-p0471-on-2007-dodge-ram-3500.html

-------------
P0304 Error code?

http://howtobyme.blogspot.com/2011/11/p0304-error-code-on-dodge-neon.html

-----------------


OBDII scan is receiving NO BUS CODE?

http://howtobyme.blogspot.com/2011/11/obdii-scan-is-receiving-no-bus-code.html

-----------
How to Clear OBD error Codes?

http://repairhelpcenter.blogspot.com/2011/11/how-to-clear-obd-error-codes-on-acura.html

----------------
Diagnosis and Testing Car Components?

http://vwrepairhelp.blogspot.com/2011/11/diagnosis-and-testing-car-components.html

--------------
Diagnostic Trouble Codes list?

Part 1.

http://repairhelpcenter.blogspot.com/2011/11/diagnostic-trouble-codes-list-for-acura_18.html

--------------
Diagnostic Trouble Codes list?

Part 2.------

http://repairhelpcenter.blogspot.com/2011/11/diagnostic-trouble-codes-list-for-acura.html

------------
OBD Code is cleared but check engine light will not RESET?

http://schematicsdiagram.blogspot.in/2012/02/obd-code-is-cleared-but-check-engine.html

--------------
Diagnostic Code 43 and 71?

http://schematicsdiagram.blogspot.com/2011/12/diagnostic-code-43-and-71-on-1991.html

------------------
Code P0132?

http://schematicsdiagram.blogspot.com/2011/12/code-p0132-on-acura-tl.html

-------------
P0031 code?

http://schematicsdiagram.blogspot.com/2011/12/p0031-code-on-dodge-dakota.html

--------------
How to get diagnostic Code without OBD Scanner on Pre 1995 cars?

http://schematicsdiagram.blogspot.com/2011/12/how-to-get-diagnostic-code-without-obd.html

------------
OBD-II Trouble Code P0300?

http://schematicsdiagram.blogspot.com/2011/12/obd-ii-trouble-code-p0300.html

-------------
Getting diagnostic code P0016?

http://schematicsdiagram.blogspot.com/2011/12/getting-diagnostic-code-p0016.html

--------------
How to Read Codes from Check Engine Light?

http://schematicsdiagram.blogspot.com/2011/12/how-to-read-codes-from-check-engine.html

-------------
Diagnostic Code P0540 continues to return and the MIL light is on?

http://schematicsdiagram.blogspot.com/2011/12/diagnostic-code-p0540-continue-to.html

-----------
DTC Trouble Code P0401?

http://schematicsdiagram.blogspot.com/2012/01/dtc-trouble-code-p0401.html

-----------------
Car misfires and error code P0306 and P0303 is shown?

http://technoanswers.blogspot.com/2012/01/car-misfires-and-error-code-p0306-and.html

-------------
Diagnostic code P0463?

http://technoanswers.blogspot.com/2012/01/diagnostic-code-p0463-on-ford-f250.html

-------------
Check engine light with codes P2195 and P2197?

http://howtobyme.blogspot.in/2012/01/check-engine-light-with-codes-p2195-and.html

------------
Diagnostic error code P0121,P0505,P1000,P2101,P2104, P2110,P2135,P2106?

http://technoanswers.blogspot.in/2012/01/diagnostic-error-code.html

--------------
P0174, P0037 and P2197?

http://technoanswers.blogspot.in/2012/02/p0174-p0037-and-p2197-on-toyota-rav4.html

-----------
P0352 Obd code?

http://technoanswers.blogspot.in/2012/02/p0352-obd-code-on-toyota-rav4.html

-------------
Error code p0402?

http://technoanswers.blogspot.in/2012/02/error-code-p0402-on-ford-escape.html

---------
Obd Code P0763?

http://technoanswers.blogspot.in/2012/02/obd-code-p0763-on-lexus.html

-------
OBD code P0301, P0430 and P0174?

http://schematicsdiagram.blogspot.in/2012/02/obd-code-p0301p0430-and-p0174.html

---------
OBD code P0500?

http://schematicsdiagram.blogspot.in/2012/02/obd-code-p0500-on-lexus-rx-300.html

-----------

This will help.

Thanks.


------------------------------------

  • Anonymous Feb 29, 2012

    Thanks, but none of those relate to the issues I'm experiencing, the P0171 code, or my truck unless I am missing something?

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What does that mean?
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What does that mean?
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