check engine light on--P0171 & P1130 codes

i got a camry 98 4cyl have
this code P0171 System to lean (bank1)
and
P1130 Manufacturer controlled fuel and air metering

what could be the problems?
hope you guys can help me out, thnx in advance!

already changed all vaccum hoses, intake pipe hose
fuel filter, gas cap.

http://www.obd-codes.com/trouble_codes/generic/p0171-system-too-lean-bank-1-oxygen-sensor.php

This is from the FAQs thread at the top of the forum:

P0171
System too Lean (Bank 1)

Possible Problems
When the air fuel ratio feedback is stable after engine warming up, the fuel trim is considerably in error on the LEAN side (2 trip detection logic)

Air intake hose loose
Fuel line pressure low (may be from running out of gas)
Injector blockage
HO2 sensor malfuction
MAF meter malfunction
Engine coolant temperature sensor malfunction

Clean MAF meter with electronic circuit cleaner<= most likely
Fix vacuum/intake leak downstream of MAF meter
Inspect fuel lines for cracks, leaks, or pinches
Replace fuel filter
Check fuel pressure at the fuel rail
Check output of HO2 sensor
Check injector performance
Check ECT sensor

Results of a history search using search function upper right:

http://www.automotiveforums.com/vbulletin/showthread.php?t=230461&highlight=camry+P1130

http://www.automotiveforums.com/vbulletin/showthread.php?t=217103&highlight=camry+P1130

http://www.automotiveforums.com/vbulletin/showthread.php?t=504962&highlight=camry+P1130

Instead of the MAF meter, it may be a MAP (manifold absolute pressure) sensor (in your engine)

i have checked my oil its lacking half in the deepstick. will that also make my check engine light "ON"?

If you mean the oil is a half-quart low, then no, it won't cause your check engine light to come on.