I am working on a 2002 stratus, 2.4L DOHC, auto, 160,000 miles. I have a high idle (2000 rpm) at start up then 10 seconds or so of idling it surges up and down. Driveable, no hesitation or bucking when cruising like bad O2 sensor I was leaning towards. Pulled some codes, P0171 (lean bank 1) and P1294 (has to do with the bad idle). No vacuum leak found so far.

Anyone experienced something similar ???? I am leaning towards idle motor, or egr valve stuck. Not my car (moms) so I dont want to throw parts at it, though I will be doing basics of plugs, air filter. I am waiting for a throttle body gasket to give that a good cleaning too. My jeep has idle issues when it needs cleaning, so maybe ?

TIA, Mike.

 

My sons 03 2.4 5-speed coupe has a high cold idle of about 2000 rpm for several minutes and then gradually settles down to a warm idle of about 700-800 rpm. It also has a slight surge when cold which happens when the air conditioner compressor cycles which I consider normal operation. The only code it shows is p441 for an evap leak I haven't located yet and it also runs fine. High idle when cold is not a problem with the manual but I can see where it would be with the auto. I think you are on the right path to begin with. Vacuum hoses are probably a good place to start along with a general tune up. Cleaning the throttle body and also cleaning and testing the EGR valve and idle motor.

 

Did you figure out what it was??? Mine is starting to do the same thing.

 

take out the air sensor (located inside the intake manifold) and clean it out. that sensor is the one that controls the rpm when the car is cold.

 

Update: My problem turned out to be the idle motor. Actually there was a small piece of plastic lodged where the pintle of the motor seats in the throttle body. This kept idle from going down, which put up a red flag of sorts for the computer and put it into some kind of limp mode for the idle.