Does any one know what they represent. I have the list but I can't seem to locate the codes. Hope I am not overlooking them. Thanks in advance.

Barry

 

did you do this?

http://vbxmaxima.8m.com/ecu.html

if you can get these codes.. then i can help you.. or Daniel or Medsonic

 

0703 - Three Way Catalyst (left bank)

0404 - undefined - not sure

 

0404 is an Oxygen Sensor

Front Heated Left Oxygen Sensor i think

ok 0303 is Front Heated Oxygen Sensor.. but i dunno..

 

My FSM does not show a code 44 but I have a 95.

 

So i guess Barry still has is stock y-pipe on.. that would cause the fail on one of the cats..

and the O2 sensor

Maybe your Front Heated O2 Sensor is bad.. and you need to replace it.. before you do anything.. see what Daniel B. has to say first.. but my $0.02

If it is your O2 Sensor.. you can see it be climbing under your car behind the right wheel well.. if you look up you will see a connector stuck in the y pipe .. it has 3 wires connected to it and it looks like a fat double AA battery

if you have an opened ended wrench it takes 5 mis to replace this part.. you can follow it all the way up to the top of the engine.. i think it plugs into a connector which runs over to the left wheel well runs up to the top of the engine and fits right infront of the Valve Cover..

The part usually cost about $80 at your local dealership.. and $60 from Vester Nissan and Southpoint Nissan.. however that means you factor in shipping... and you may want to do it now..

I repeat do not pay your dealer to change it.. its too simple.. if they are doing it for free then ok..

but I could be wrong about the whole thing.. and just babbled for 4 mins for no reason

 

All OBD-2 Diagnostic Trouble Codes are four numbers, and the first number is always 0 or 1. May we assume that your reported 44 and 73 are actually 0404 and 0703?

 

Diagnostic Trouble Code 0404 points to a problem with the ABS/TCS Communications line. ABS = Antilock Braking System. TCS = Traction Control System. Pulse signals are exchanged between the Engine Control Module and the ABS/TCS control unit to assure smooth engine operation during TCS operation.

This malfunction is detected when the ECM continuously receives an incorrect voltage from the ABS/TCS control unit. Possible causes include...
- Harness or connectors (The communications line circuit between the ECM and the ABS/TCS control unit is open or shorted.)
- ABS/TCS control unit
- Discharged or faulty battery

 

Diagnostic Trouble Code 0703 points to a problem with the three-way Catalytic Converter.

The Cat is one of the principal components of the emissions control system. The Engine Control Module monitors the signals from the two front Oxygen Sensors and the one rear Oxygen Sensor. The signal frequency of each sensor indicates something about the condition of that sensor. A comparison of the frequency of the front sensors with the rear sensor indicates something about the condition of the Cat.

This malfunction was detected when the ratio of the signal frequency from the left bank front Oxygen Sensor to the signal frequency of the rear Oxygen Sensor exceeded a critical threshold value. This indicates that the Cat does not have enough oxygen storage capacity. Possible causes include ...
- Three-way catalyst
- Exhaust tube
- Intake air leaks
- Fuel injectors
- Spark plugs
- Ignition timing

 

SprintMax..I have the STillen Y-pipe...2 yrs now. When that pipe was put in, the threads on the front O2 sensor were stripped so I had to replace it.
Here's the history.
Last summer I had the engine cleaned and it set off the engine light for the first time. The water caused the engine sensor (might be O2) to act abnornally. Reset. This winter I (the car, but sometimes I did also) started having problems starting. The starter kicks in but the engine does not want to ignite. At someone's suggestion I would leave the leave the key in the ACC position for a few seconds before starting. That helped sometimes. The problem went away for a while. Engine light on in Dec. I had Nissan diagnose a coolant temp sensor the problem . But I question the fix, when they asked me if I did not have any wierd temp readings. I didn't. Maybe nothing was wrong and they charged me for the cheap problem to fix...that's my non-mechanical opinion.
I have been having these weird starts lately. The starter would turn normally but the engine would stall right after it starts. This has caused the engine light to come on in the past. If this happens, I have to step on the gas while starting to get the car started otherwise its a no go. When the car is warm I have no starting issues at all.The last time it happen, yesterday evening, the car was sitting for about 8hrs. I turned the key, the started cranked away and the engine was about to kick in when it kinda hiccup/burp (for lack of a better description)and then starts, but the engine light stayed on, thus the codes above. It sounds almost as if the engine misfired or is struggling with one of the components needed to start a car...Air, gas, electricity.
I am at 90K now and I had the usual 60K tuneup.
My friend thinks its the plugs or the coil packs.
Daniel B.
1) my muffler is going. outer shell has rusted thru and god knows what else. NY/Vermont winters.
2) I have the STillen intake. I will check for leaks.
3) I have been added Fuel injector cleaner regulary

Thanks sorry about the length

Barry

 

Your fuel injected engine has an Engine Coolant Temperature Sensor. This sensor sends a signal to the Engine Control Module (the computer). When the ECTS sends a "cold engine" signal the ECM responds by instructing the fuel injectors to deliver a rich mixture. The rich mixture helps a cold engine to start and run smoothly during the warm-up period. This is similar to the operation of the choke on a carbureted engine.

There are other problems which cause cold starting and driveability problems, but the ECTS is the first thing to check. This can be done with an ohmmeter.

On the 4th Generation Maxima engine the Engine Coolant Temperature Sensor is located in the water outlet tube close to the engine end of the upper radiator hose. There are two sensors in that vicinity. The one nearest the hose is for the dashboard temperature gauge. The ECTS, the one you're interested in, is adjacent to the the gauge sending unit. There is a good picture of these sensors in the Haynes manual on page 3-7.

With the engine cold, disconnect the ECTS and measure its resistance. Reconnect the ECTS, start the engine, and run it until fully warmed up. Stop the engine, and repeat the resistance measurement. The "warm" reading should be a much lower value than the "cold" reading. These are the specs:
Engine coolant temperature 68F, ECTS resistance 2.1 - 2.9 Kohms
Engine coolant temperature 194F, ECTS resistance 0.24 - 0.26 Kohms
(Roughly a factor of ten difference.)

The ECTS is a relatively inexpensive sensor and something the home mechanic can replace without special tools.

 

Perhaps the fuel rail lost its residual pressure during the idle period. Next time you have a similar period of disuse, try this experiment. Turn the ignition key to ON, wait 5 seconds, turn the key to OFF. Repeat this ON/5/OFF sequence twice more. This sequence gives the fuel pump extra time to build normal fuel rail pressure. If your engine starts readily and runs well after this sequence, that will confirm this fuel pressure hypothesis.

Possible causes loss of residual fuel system pressure include
- an external leak anywhere in the fuel loop
- a leaky check valve
- a bad fuel pressure regulator
- one or more fuel injectors which sticks open

 

A bad plug or coil pack usually causes a misfire and sets a Diagnostic Trouble Code in the 0603-0608 range. The DTC identifies the bad cylinder.