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, GMC Mechanic
Category: GMC
Satisfied Customers: 28315
Experience:  GM training and dealer tech for 14+ years. Diagnostics
Type Your GMC Question Here...
Pete is online now
A new question is answered every 9 seconds

Have 1997 gmc box truck with 5.7 throwing up code po1870,

Customer Question

Have 1997 gmc box truck with 5.7 throwing up code po1870 , po751 . Checked and ohmed out shift solenoid a a and b or 1 and 2 shows 25 so those check out okay is the po1870 code the Tcc connection on the valve body will that fix that problem for code po1870 also throwing code for crankshaft sensor but checked wiring no problem there any ideas
Submitted: 1 year ago.
Category: GMC
Expert:  Pete replied 1 year ago.

My name is ***** ***** I am a professional here at Just Answer. I noticed that your question had not received 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.

The codes P1870 here can indicate an internal mechanical fault in the transmission itself with the valve body or another internal mechanical component and is most likely tied into the P0751 code as well.If the valve body has not been tested at all this needs done to see if it needs replaced or if there is another internal mechanical fault in the transmission needing replaced to correct this fault here.

If you have a cam/crank correlation fault code set this may be an issue with a worn gear on the distributor shaft needing replaced as I have seen before.If you can post this code here this will help.

If more help is needed, use the reply tab to continue our conversation. If no further assistance is needed, kindly rate my service.You can rate at any time and we can continue to work on your question as this will not close out your question.Keep in mind in some cases it can be difficult to fully diagnose or help repair your vehicle without seeing it and I work on delivering the best possible answer from what I see to work with.

Thanks Pete