maxdis1

P. S : the Ohms registered by my voltmeter for the Knock sensor was 575 Ohms.

Kevlo911

iTrader: (36)

0303
Diagnostic Trouble Code 0303 indicates a problem with the front Oxygen Sensor on the left cylinder bank. The left bank is also called the front bank. It is cylinders 2,4,6. A normal signal sweeps back and forth between 0.2 volts and 0.8 volts. This malfunction was detected when the Engine Control Module received a signal from the sensor which was a constant value of approximately 0.3 volts.

Possible causes include ...
- Harness or connectors (the sensor circuit is open or shorted).
- Defective Oxygen Sensor

This could be related to the KS code. FIx this and the KS should go away. Also what kind of gas are you using?


0705
Diagnostic Trouble Code 0705 points to a problem with the Evaporative Emission Control System.

This malfunction is detected when the EVAP control system has a leak or the EVAP control system does not operate properly. (EVAP = EVAPorative emissions.)
Possible causes include...
- incorrect fuel tank vacuum relief valve
- incorrect fuel filler cap
- fuel filler cap vent remains open or fails to close
- foreign matter caught in fuel filler cap
- a leak in the line between the intake manifold and the
EVAP Canister Vacuum Control Valve
- foreign matter caught in the EVAP CVCV
- leaks in the EVAP canister or fuel tank
- leaks in the EVAP purge line (pipe and rubber tube)
- EVAP purge line rubber tube bent
- blocked or bent rubber tube to EVAP control system pressure sensor
- loose or disconnected rubber tube
- EVAP CVCV and circuit
- EVAP Canister Purge Volume Control Solenoid Valve and circuit
- absolute pressure sensor
- tank fuel temperature sensor
- MAP/BARO switch solenoid valve and circuit
- blocked or bent rubber tube to MAP/BARO switch solenoid valve
- O-ring of EVAP CVCV is missing or damaged
- water separator
- EVAP canister saturated with water
- EVAP control system pressure sensor
- refueling EVAP vapor cut valve
- ORVR system leaks


This is a "jackpot" DTC. It points to so many things you don't know what to check. It is often combined with another DTC which is more specific and therefore more helpful.



0903
Diagnostic Trouble Code 0903 indicates a problem with the Evaporative Emission (EVAP) Canister Vent Control Valve or its associated electric circuit.

This part is used by the Engine Control Module to perform the fuel system leak test. Since it is used only for self-diagnosis your engine will run perfectly well despite the dashboard Malfunction Indicator Lamp.

The EVAP canister and this valve are located under the car, near the rear left tire. You might check to make sure all the electrical connectors in that area are secure.

There's no telling how expensive the repair will be, because no definite diagnosis has been made. Maybe you just have to re-plug a loose connector. Since the EVAP system is part of the emissions control system you might have warranty coverage.

maxdis1

Thank you for your help. I have actually used the info in your sig to interpret the codes before posting . You have confirmed my inclination of the o2 sensor being a possible cause from a defective KS.
Thanks again.

d_warner

My O2 sensor went out cause of my knock sensor. Gets to be rather expensive.

DAVE Sz

iTrader: (2)

I think you have it backwards maxdis. A bad O2 sensor will trip the KS code even if the KS is good. A bad KS won't do anything to an O2 sensor. since the KS retards the timing to prevent any damage.

mechanicaljoint

a KS is a "dumb" sensor. there is a tiny piezo element that picks up vibration and transmits an electrical signal proportionate to the vibration level back to the computer. the compute does the thinking and throws the code and adjusts the timing to eliminate the vibration (like Big D said above). the KS is a pretty simple thing. anything the causes excessive vibration (knocking, cylinder misfire, etc.) in the block will trip it.

i'd leave that for the last thing you replace...like Kevlo911 said above...

Maxjm

So if you have 0303 and 0304, more than likley you just have a bad o2 sensor that is triggering the knock sensor code. Now this is where I get confused; if you really do just have a bad o2 sensor that is setting off the knock sensor code and your knock sensor is in working condition, does that mean you really aren't losing any performance...or does the knock sensor retard timing due to the bad o2 sensor, thus making a decrease in performance? Sorry, sort of a wordy question, but I just get confused on this part.

DAVE Sz

iTrader: (2)

You still are losing performance cause the ecu gets the KS code and retards the timing to prevent damage.

maxdis1