Emission control light

the fule tank as i small oil tank above it and drips oil in to flule after 70000 miles it runs out needs replaseing

P0453 means EVAP emission pressure sensor high input. Possible causes:
- Faulty Evaporative Emission System (EVAP) Pressure sensor
- Evaporative Emission System (EVAP) Pressure sensor harness is open or shorted
- Evaporative Emission System (EVAP) Pressure sensor circuit poor electrical connection.
Code p0701 means Transmission control system range/performance. Possible causes:
- Open or short transmission control system circuit
- Poor transmission control system electrical connection
- Check powers and grounds to Transmission Control Module (TCM)

When the service engine soon light (Also called the check engine light or engine management light) is turned on this is to alert you to the fact that Powertrain Control Module (computer) has detected a failure somewhere in the systems it controls you may not feel any difference in the way the engine runs, this can be the transmission or the engine or emission system, there are fault codes set in the modules memory for these faults. What needs to happen now is to have the powertrain control module scanned with a special tool called an OBD2 electronic engine control scanner or a OBD2 code reader. Once the code(s) are read then you must perform the diagnostics for each code and make the appropriate repairs based on the findings of the diagnosis that was performed, this is called doing "Pinpoint" testing.

It means your vehicle's computer has determined that a component or system in your emission control system is not working properly.
When the light comes on, one or more diagnostic trouble codes (DTC) are stored in the engine control module. These DTCs remain even if the light goes out. To address a Check Engine Light problem, the DTCs are retrieved and the appropriate troubleshooting information is followed in order to determine the problem.
Every vehicle manufactured in the U.S. has to first pass an Environmental Protection Agency (EPA) test called the Federal Test Procedure. This sets the acceptable limits of wear and/or failure for the emission control system-i.e., what conditions will ultimately cause a Check Engine Light to illuminate. These standards are closely regulated. If the emission control system is faulty and the vehicle is polluting the air, the Check Engine Light illuminates to alert the driver of this condition. (Note: A vehicle in this condition would fail an emissions inspection or smog check.)
Don't confuse the Check Engine Light with the maintenance or service light. These lights illuminate when a routine service is due. They are usually triggered by mileage, gallons of gasoline consumed, or some other type of vehicle-use measurement.

That is a problem in the evaporative emission control system.
Could be anything causing it
Clogged filter in the charcoal canister
A leak in one of the vacuum lines
The purge valve not working,,,etc.
The best thing is to take it and have it checked out, they might have to do a smoke test to find the problem.
All they do is inject smoke into the system, if there is a leak the smoke will come out of it. All it takes is a pin hole in these emission systems to screw it all up.

P0446 Evaporative Emission System Vent Control Circuit.
The following are descriptions of all Evaporative possible codes:

P0441 Evaporative Emission System Incorrect Purge Flow
P0442 Evaporative Emission System Leak Detected (small leak)
P0443 Evaporative Emission System Purge Control Valve Circuit
P0444 Evaporative Emission System Purge Control Valve Circuit Open
P0445 Evaporative Emission System Purge Control Valve Circuit Shorted
P0446 Evaporative Emission System Vent Control Circuit
P0447 Evaporative Emission System Vent Control Circuit Open
P0448 Evaporative Emission System Vent Control Circuit Shorted
P0449 Evaporative Emission System Vent Valve/Solenoid Circuit
P0450 Evaporative Emission System Pressure Sensor/Switch
P0451 Evaporative Emission System Pressure Sensor/Switch Range/Performance
P0452 Evaporative Emission System Pressure Sensor/Switch Low
P0453 Evaporative Emission System Pressure Sensor/Switch High
P0454 Evaporative Emission System Pressure Sensor/Switch Intermittent
P0455 Evaporative Emission System Leak Detected (large leak)
P0456 Evaporative Emission System Leak Detected (very small leak)
P0457 Evaporative Emission System Leak Detected (fuel cap loose/off)
P0458 Evaporative Emission System Purge Control Valve Circuit Low
P0459 Evaporative Emission System Purge Control Valve Circuit High
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At least the cap isn't loose for the gas tank.

I would clear the code with an OBD-II Scanner 'erase code' button, and see how long it takes for it to come back.

po442 is evap emission control system leak (small) 1 of the lines for emissions is leaking. po455 is-- emission control system leak (large). turn off light with code scanner after it is fixed.

Yes the problem is effecting the emissions controls. Sounds like the timing if off. Take the vehicle to you local Auto Parts Store and most will scan the ECU for fault codes. This code will help you to figure out the problem.

audi a4 tdi Emission control system light on dash