2000 Toyota Sienna with 74K miles. Van purrs like a kitten when you start it cold. BUT as soon as it warms up, it starts to run a little rough. Almost like it’s skipping. Not noticeable when riding down road. After engine warms up and you’re idling it’s almost like it wants to cut off but it never does. Any ideas?
I suggest you have have any engine error codes read. Some may not trigger the CEL but you may still have some. Some places will read them for FREE. Try Autozone or Advanced Auto Parts. Get the exact code not just their translation into English and post it back here. It likely will have a format like P1234.
I would also suggest getting caught up on any maintenance that may be past due, like oil, air and fuel filters, oil change, spark plugs and wires etc. These thing may or may not be part of the problem, but you should do them anyway and you can eliminate a lot of possibilities that way.
ERROR CODE P0171 System to lean. Sparkplugs, air filter, fuel filter were changed one week ago. It seems like I hear air blowing at the back of the engine although by sticking my hand back there I can not feel it.