The 2000 mountianeer starts and runs fine in warm weather, 50 degrees or above. In colder weather it will start but it will not sit and idle and stay running, it just keeps cutting off until it is completely warmed up. You have to keep starting it and sit with a gentle pressure on the accelerator if you push the accelerator to far it cuts off. Once you can drive it a few miles, usually taking off requires using both the accelerator and brake at the same time, it runs just fine. So therefore it runs great about 7 months out of the year until the weather turns cold. A mechanic replace a few pricey electronic parts last winter but it didn't seem to help.
Have a mechanic take a look at your throttle position sensor and engine idle sensor. Make him manually adjust them as opposed to just putting in new ones. It may require that you have to have a higher idle than normal. Your underlying cause is going to be that I am sure you have a lot of miles on your engine.
There is a much richer fuel mixture during a cold start, the colder the engine the richer the fuel mixture
retarded ignition timing causing the fuel to burn for a longer period of time makes the engine heat up faster
anything that doesn't allow the mixture to be properly metered, like vacuum leaks, bad temperature sensors, or O2 sensors, MAF or MAP sensors, bad EGR valves or PCV valves hoses or tubes,
and or
anything that will cause the fuel mixture not to burn properly, like worn spark plugs, or any other ignition part, wires, cap, rotor, timing, compression, will cause poor start or no start conditions that are worse in lower temperatures,
also low voltage, week battery, slow cranking of the engine can also cause hard to start conditions
Mate this issue is cold start. You must check cold start choke, it works with coolant by pass to the throttle body, follow the thin coolant rubber pipe going to the throttle if you know what I mean, there is the spring coil built in the housing when the car is cold it hold down the acceleration high till it get the hot coolant from the engine to expand and the car returns to normal idling. If it is ECM control disconnect the Coolant Temp sensor and see how she goes
Must work give a shot let us know
AD
SOURCE: The 2000 mountianeer starts and runs fine but shuts off
CHECK THE COLD START ENRICHMENT VALVE AND OR THE IDLE CONTROL VALVE. I AM ASSUMING THAT YOUR VEHICLE IS FUEL INJECTED. ONE OF THOSE HAVE GONE BAD.
938 views
Usually answered in minutes!
I have the same problem and if you had electronic parts replaced and it's still doing it, it could be you need the air holes cleaned. That is what I'm going to try this weekend.
Good luck.
I am in Korea and the same thing is happenining to me. What can I do?
×