How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask sprinkles08 Your Own Question
sprinkles08
sprinkles08, ASE Certified Technician
Category: Transmissions
Satisfied Customers: 22294
Experience:  Chrysler/Dodge/Jeep master tech ASE Master and Advanced Certified, Chrysler/Dodge/Jeep Master Certified, Trans Specialist
9825021
Type Your Transmissions Question Here...
sprinkles08 is online now
A new question is answered every 9 seconds

My 6.7l 6 speed manual wouldn't rev over 2500rpm in 6th.

Customer Question

My 6.7l 6 speed manual wouldn't rev over 2500rpm in 6th. Today I tried it again and it was fine. I also realized the sometimes the mpg goes down to14mpg without any reason, highway, no load no towing
Submitted: 1 year ago.
Category: Transmissions
Expert:  sprinkles08 replied 1 year ago.

Hello and welcome to JustAnswer!

It's possible that the engine was producing low power due to a fuel delivery issue or lack of boost, or the ECM may have derated power due to an abnormal sensor input or injector circuit issue. It's not uncommon for the turbo ring to stick and cause a lack of boost.

The first step in diagnosing the problem will be to see if any fault codes have set. Have you checked for codes?

Customer: replied 1 year ago.
No, I didn't check for error codes. But there are no error codes on the display.
Expert:  sprinkles08 replied 1 year ago.

The first step in diagnosing the problem will be to connect a code reader or scan tool to the data link connector and see if any codes are stored in the ECM.