2003 sonata2.4g4js,idling 1700rpm,when hot, just replaced MAF sensor,plull the plug out of the MAF idle returns to normal,

SOURCE: 2003 Honda Civic runs hot when idling.

Check the cooling fan switch. It appears your auxiliary electric cooling fan isn't going on when at idle. and engine temp increases. While you are driving, air is being rammed thru your radiator as you cruise along, so it isn't overheating, at idle, that isn't happening, and the fan should go on as the temp goes up. When the ac is switched on, the fan is being signaled to operate due to the heavy ac load on the cooling system.

SOURCE: 1989 Chevrolet C1500 with 5.7L V-8. Engine dies

fuel pump is working but when accelerating it doesnt pump enough fuel up to the engine then it will fall on its face if it is a electric pump you may have to drop the tank if it is inside and replace it if it is on the engine replace it thats what is exactly wrong with it

SOURCE: 2003 Ford Expedition, low idle, no power while driving.

sounds like water in gas. add gas line antifreeze. 2 bottleshould do it.

SOURCE: 2003 audi A4 2.0 fsi, has misfire on idle

this is going to sound crazy BUT i would (and have) take your car to a skoda dealer, labour cost 1/2 that of audi(i worked for audi for 11 years)and the parts are out of the same box.have you replaced H.T.leads as thet are carbon fibre and can cause the same symptoms.also ask to speak to audi area technical manager when next in your area.he is factory trained.

SOURCE: My 2003 GMC Sierra Idles Rough And Cut Off

Before replacing the O2 sensors, I would check the fuel pressure. You may also try to have someone pull a trouble code from the powertrain control module to verify why the engine light is on. Do not replace any parts until this is done, otherwise your going to be guessing at the root cause, and it will get expensive with part replacement.

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