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, Technician
Category: Jeep
Satisfied Customers: 29116
Experience:  Over 17 years diagnosing and repairing automobiles various makes and models with some training and certifications.
Type Your Jeep Question Here...
Pete is online now
A new question is answered every 9 seconds

Engine runs fine sitting still, boogs down when attempting

Customer Question

engine runs fine sitting still, boogs down when attempting to accelerate when in gear and on highway--- code po108
JA: Tell me a bit more about what's going on so he can help you best.
Customer: that's it, it accelerates fine sitting still, when attempting to accelerate while traveling it acts as if it has a clogged exhaust, no exhaust codes,cat recently replaced, code po051 and po108
JA: Are you hoping to fix this yourself?
Customer: yes
JA: Great! What have you tried so far?
Customer: replaced plugs,air cleaner, checked for vacuum leaks, engine is fine sitting still, no power on acceleration and getting codes that all cylinders are misfiring
JA: Leaks can get messy. The Jeep Mechanic will know what to do. Is there anything else the Jeep Mechanic should be aware of about your Jeep?
Customer: 2003 grand cherokee,4.0 in line 6 cylinder engine
JA: Our top Jeep Mechanic is ready to take your case. Just pay the $5 fully refundable deposit and I'll fill the Jeep Mechanic in on everything we've discussed. You can go back and forth with the Jeep Mechanic until you're 100% satisfied. We guarantee it.
Submitted: 1 year ago.
Category: Jeep
Expert:  Pete replied 1 year ago.

Hi my name is ***** ***** I will be happy to assist with this today.In some cases I may need more info to assist better.I apologize for any delay.

Code P0051 indicates oxygen sensor bank 2 sensor 1 heater circuit fault.This wont affect the running of the engine and is usually the sensor itself at fault.

Code P0108 indicates MAP sensor voltage to high.This will cause the issue you have here.If the map sensor was not replaced this is the most common cause for this fault code here.I would check the map sensor wiring and make sure it is o.k. as well as any hose connections.if all of these are found to be o.k. the sensor itself will need replaced.The map sensor is located near the throttle body as shown here.

The cost from a dealer is $114 but may be cheaper at a local parts store.

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