99 Sonata - no power at times

I just bought a 1999 2.4L, 4 cyl. Hyundai Sonata.
Occassionally I step on the gas and the car will barely move, then after a
few seconds it will start to go. This seems to happen only within the first
15 minutes of starting the car and when I am taking off from a complete
stop.
I have changed the plugs, wires, head gasket, transmission fluid&filter,
oil fluid&filter,timing belt&crankcase sensor.
The Engine light is on (solid). The engine code is Error Code:171 Left
Bank Lean.
Any ideas?
Thanks!

 

You'll want to check to see if unmetered air (i.e. not going through the
air flow sensor) is entering the engine. Check the PCV valve hose for
breaks. Check the hose between the throttle body and the air flow sensor
to be sure it's installed properly and has no cuts or breaks which would
allow air to enter.

If all that is okay, you probably have a problem with your upstream oxygen
sensor or your air flow sensor.

 

I'm not sure how an inline 4 can have a "left bank", but I'm not real
familiar with Hyundai codes. I'd take it to a reputable garage and have
them take a look. Sounds like you aren't getting sufficient fuel and
this could be due to a number of problems such as fuel pump, clogged
fuel filter, fuel injector, sensor error, etc.


Matt

 

On inline engines, the codes for "Bank 1" or "left bank" are used, and the
codes for "bank 2" or "right bank" are not. It's pretty standard
terminology, but I understand how it can be confusing.