In this case the problem is noticed on ford explorer 4.0L engine.
The car will not idle when cold,but runs fine when engine is warmed up.
There is no check engine light on dash and no error codes stored in cars computer.
On that basic the troubleshooting possibilities is as follows :-----
The upper intake gasket are a known concern on your 4.0 but in most cases if its leaking it will set and store the lean codes P0171 and P0174. if you not getting any fault codes its not likely you need to replace the gasket set as of yet. The problem you are describing sound more like your IAC (idle air control valve is sticking due to be dirt and sludged up. Before doing anything else try removing it and cleaning it real well with some carb cleaner and while there also take a soft cloth and or tooth brush and clean the throttle body bore and throttle body plate. Once you have don't this, remove the negative battery cable for about 10 minutes to reset the PCM (computer).
The IAC mounts to the throttle body and is held on with 2 8mm bolts.See the image diagram shown below:-----
This details will help.
Thanks.
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The car will not idle when cold,but runs fine when engine is warmed up.
There is no check engine light on dash and no error codes stored in cars computer.
On that basic the troubleshooting possibilities is as follows :-----
The upper intake gasket are a known concern on your 4.0 but in most cases if its leaking it will set and store the lean codes P0171 and P0174. if you not getting any fault codes its not likely you need to replace the gasket set as of yet. The problem you are describing sound more like your IAC (idle air control valve is sticking due to be dirt and sludged up. Before doing anything else try removing it and cleaning it real well with some carb cleaner and while there also take a soft cloth and or tooth brush and clean the throttle body bore and throttle body plate. Once you have don't this, remove the negative battery cable for about 10 minutes to reset the PCM (computer).
The IAC mounts to the throttle body and is held on with 2 8mm bolts.See the image diagram shown below:-----
This details will help.
Thanks.
See below latest solved car problems :-----