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 Pete Your Own Question
Pete, Automotive Mechanic
Category: Transmissions
Satisfied Customers: 27872
Experience:  GM and Mercedes vehicle technician.17 years experience.
Type Your Transmissions Question Here...
Pete is online now
A new question is answered every 9 seconds

2005 GMC Envoy 4.2LSpeedometer maxed @ 120+. Transmission

Customer Question

2005 GMC Envoy 4.2L
Speedometer maxed @ 120+. Transmission Shifting erratic. RPMs fluctuating. Shuts down at stops on at times.
I changed the spend sensor and no change.
Last codes I got was: CO055, PO171, PO340, PO455 and PO017
Thanks for any help I can get.
Submitted: 2 years ago.
Category: Transmissions
Expert:  Pete replied 2 years ago.
My name is ***** ***** I am a professional here at Just Answer. I noticed that your question was not getting a response and thought I would see if you still need help with this.I apologize for the delay and I hope I can still assist you with this here.
Inspect for any shorted or damaged wirign on the engine and if an issue is found it will need repaired to correct this here.If all wiring is found to be o.k. this may be a possible fault with the engine computer itself shorted internally needing replaced.I would clear out all codes and operate the vehicle and let me know which codes come back again.
Thanks Pete