The ECU will always store diagnostic trouble codes (DTC) from lowest
numerically to highest numerically.

Since the 2 codes you listed are opposite in nature, I would start by
checking the things that have an effect and measure air/fuel ratio.

First, the stuff that will have an effect on air/fuel ratio:

Check the condition of the black plastic tubing that runs from the air
filter housing to the throttle body for cracks, holes, or gaps.

Check the air filter to make sure it is not clogged, torn, or warped.

Check for any manifold vacuum leaks or disconnected vacuum hoses, paying
attention to vacuum switching valves to make sure they are not cracked or
damaged.

Check the mass air flow sensor to make sure the connector is secure.  There
is a wire inside the MAF sensor that heats up, and is cooled by air passing
through.  If the wire is dirty, it won't sense properly.  You can try
cleaning it by giving it a shot of carburetor cleaner and letting the liquid
drip out of the opening.  Do not damage the wire, or you will need a new MAF
sensor.   My guess is that a dirty or clogged MAF sensor is the cause.

If you use a lot of cheap gas, try a bottle of Chevron Techron fuel injector
cleaner and see if that helps.

If you used anything other than OEM spark plugs and related ignition parts
when you replaced them, stick to OEM the next time you replace them.  Some
aftermarket ignition parts don't last as long as OEM.  Check the condition
of the spark plugs to see if they have a uniform, fine-gray color.

Next, check the stuff that measures the air/fuel ratio, which is basically
the O2 sensor.  Use your shop manual and a multimeter to check the O2 sensor
and while you're at it, check to make sure the connector is not damaged or
loose.  If the O2 sensor does not check out according to the manual, replace
it with an OEM O2 sensor.

Good luck!

It turned out to be a burnt spark plug wire. I found it a week ago, but for
some reason my regular computer isnt configured to post to newsgroups.