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 Jeep Service Your Own Question
Jeep Service
Jeep Service, Jeep Owner
Category: Jeep
Satisfied Customers: 4848
Experience:  14 years with AMC/Jeep Specializing with pre-1994 Jeep products.
Type Your Jeep Question Here...
Jeep Service is online now
A new question is answered every 9 seconds

I have a 2002 Jeep Liberty 2.7. When slowing to a stop the

Customer Question

I have a 2002 Jeep Liberty 2.7 . When slowing to a stop the vehicle will idle down extremely low and shake as if it were going to die, but never did. Seems to run fine when accelerating and driving . Set off check engine light. These are the codes in order:
P0203, P0201, P0152, and P0205. I know the three P02 codes are for the injectors on the drivers side bank and the P01 is for the O2 sensor.
Submitted: 2 years ago.
Category: Jeep
Expert:  Jeep Service replied 2 years ago.

Hello. Welcome to Just Answer. Please allow me to assist you. This is a common problem on these vehicles. The idle speed is actually controlled by a devices called the Idle AIr COntrol Valve. This unit moves back and forth as commanded by the computer. The more it moves towards the open position, the more air is admitted to the intake manifold. This additional air increases the idle. If the valve is faulty, dirty (carbon buildup is common), the valve does not move properly. This is what causes the engine to shake at idle, the valve is not opening to where it should be. Cleaning the idle valve is possible, but, since this is an older vehicle, I would recommend replacement of the valve. The recommendation I have for you on this issue is to go to a Jeep dealer parts dept and purchase a new Idle control valve and install it.

If you have any questions, please feel free to reply.

Thanks for choosing Just Answer. It was a pleasure to assist you today. I trust my input to your request is satisfactory to you and meets your expectations. A positive rating would be greatly appreciated for my assistance on your inquiry.

Thanks in advance and thank you again for choosing Just Answer

Customer: replied 2 years ago.
After driving this morning prior to doing any repairs, it slowed down from 70mph to 40 mph on its own and would not go any faster no matter how hard you pushed the accelerator. Did this for a few miles, and then started driving fine.
Expert:  Jeep Service replied 2 years ago.

That sounds like a sticking throttle plate. I would recommend a throttle body cleaning in conjunction with the idle valve replacement