I have a 1990 Ford Ranger that idle roughly on starting up it takes 30 minutes to an hour who finally sitting and the engine goes in and out as if it wants to cut off I don't know if it's my IAC but i need help finding the problem
My car has an automatic transmission.
These engines were known to get a carbon build up on the intake valves and the excessive carbon buildup will soak up any fuel the injectors spray when it is first started until it gets warmed up. The buildup can cause low power, misfiring, rough idles, and hard starting. The carbon should be cleaned using an intake cleaner sucked into the intake and then cleaning the throttle body and IAC valve. You may even need to remove and clean the EGR valve if the engine has one. Some do and some don't. If after cleaning the EGR you are still having problems, you may need to have the injectors cleaned out also. If you need assistance with any of this, a technician from YourMechanic can come to your home or office to inspect your rough idle and perform any needed services.
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