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Michael Solis
Michael Solis,
Category: Car
Satisfied Customers: 174
Experience:  Lead Tech at Solis Auto Repair
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Turbo underboost code and throttle positioning code, don`t

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turbo underboost code and throttle positioning code
JA: Just to clarify, what's the exact code? And have you tried to reset it?
Customer: don`t know the code # for the under boost but the # for the throttle postioning sensor code is PO299
JA: What year is your Turbo?
Customer: 2006 6.0 litre
JA: Are you fixing your Turbo yourself? What have you tried so far?
Customer: Had dealer do a top engine clean at 36,000 miles and been adding sea foam treatment to the fuel
JA: Anything else you want the mechanic to know before I connect you?
Customer: just that I reset the lite, stays off for awhile and then comes back on. I only have 73,000 miles on the truck

Hello, my name is***** will be helping you out! I have over thirteen year of experience in the automotive world for numerous different makes & models. I enjoy doing what I do, it is my life. Now on this case, there is several possibilities. First question is do you notice any drive ability issues?

Customer: replied 1 month ago.
sometimes feels like a loss of power when pressing down on the throttle pedal

Do you have a scan tool?

to do phone service would like to know if you have a scan tool

If not I can only give a good explanation and the possibilities

Customer: replied 1 month ago.
no I don`t I had a friend do it a week ago

Ok then I can only explain the possibilites and procedure if you would still like the phone service

Michael Solis and other Car Specialists are ready to help you
Customer: replied 1 month ago.
give me a call please
1. Monitor the Manifold Absolute Pressure (MAP) sensor reading on the scanner at the same time as monitoring the exhaust backpressure reading. Also monitor the exhaust backpressure sensor voltage on the scanner or by back probing the Violet/Light Blue (VT/LB) wire at the sensor. The exhaust backpressure sensor should read roughly 14-15 PSI or about 1.0 V Key On Engine Off or at idle.

2. If the reading is incorrect, check the Brown/White (BR/WH) wire at the sensor for 5 V and the Gray/Red (GY/RD) wire for a good ground. If OK, replace the sensor.

3. If the reading is OK Key On Engine Off or at idle, rev the engine and see how high the MAP sensor is going when the exhaust backpressure goes to 34 PSI. If the MAP sensor is not increasing to within roughly 5 PSI of the exhaust backpressure sensor, check for a restricted exhaust. Start with checking to see if the truck is equipped with a catalytic converter. If so, drop it loose and recheck operation. If the reading is then better, address the restricted exhaust.

4. If the reading is still high with the exhaust dropped loose, check for a malfunctioning Variable Geometry Turbocharger (VGT). Refer to TSB 06-23-2 for information on cleaning and repairing the variable part of the turbo and recheck operation.

here is the picture