From Autozone Code reader Print out:

For codes: P0410, P0170

Code: P0410:
The PCM has determined that a malfunction exists in the secondary air injection system.

Trouble shooting P0410 (domestic)
Definition:
Secondary Air Injection system fault.

Explanation:
The Air injection system is monitored for faults.

Probable Causes:

1. Circuit Relay defective or fuse open.
2. Check Connector and Wiring.
3. Air pump defective, or hoses blocked.


Code: P0170
The PCM has determined that during testing the fuel compensation value for bank 1 exceeded the specified range. (Bank 1 identifies the location of cylinder #1, while Bank 2 identifies the cylinders of the opposite bank)

Trouble Shooting P0170 (Domestic)

Definition:
Fuel Trim Bank 1

Explanation:
The powertrain control module uses the oxygen sensor to calculate the air/fuel ratio of the engine. The Computer has recognized a rich or lean condition in one engine bank only.

Probable Causes:

1. If Bank one and two codes are set together suspect fuel pressure or Mass Air Flow sensor.
2. Oxygen sensor defective.
3. Ignition misfire-repair
4. Fuel Injector problem.

Since both MAS codes didn't kick off, I'm tempted to go with the PCM's diagnosis that its not the MAS. I've picked up spark plugs, and MAS sensor cleaner just in case. Added lucas fuel injector cleaner (great stuff) and I'm trying to find guides to show me how to replace the spark plugs.

But you guys know more about this than I, so should I still order the MAS?
(at a gut stomping $300?)

I'l also taking the MAS sensor out, and checking the air intakes for blockages.

any insights?

Thanks.