Nissan Sentra 2003 - Stalling Problem

I have a 2003 Sentra which I have had with me since Aug 2011. I seem to have the same exact problem of stalling which I read in your closed discussion.
As I am driving it stalls. I have been able to restart within 15-20 minutes but after several tries.
Of course, the service engine soon light has been ON for a long time (maybe 2 years since I have owned it). The stalling problem is rather new (only 1-2 months max). Most of the times the car runs smoothly (within inner city driving conditions and usually no highways).
Mechanic says there are two Codes. (1) is about the catalytic converter. (2) P0301 is the other code.
Any help is appreciated.
Sudhi

The stalling problem might be with the crankshaft position sensor being effected by heat.

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The crank sensor informs the computer whether or not the cranshaft is rotating. If the computer loses the signal from this sensor, the computer see’s no reason to operate the ignition and fuel systems so the engine shuts off. Then if you wait long enough the sensor cools back down and starts working again and the engine starts and runs.

Tester

P0301 - Cylinder 1 Misfire Detected.

How many miles are on your car? It sounds like it may be overdue for spark plugs. Dirty injectors and low compression can also cause misfire codes. Depending on which code was on all this time, a misfire can cause the catalytic converter to fail. It can also cause other problems that you may also be facing.

The cat code is likely due to the misfiring, not the other way around. So figuring out what is causing the misfire is where to start. Could be any of a fuel system problem, a crank or cam sensor problem, electronic ignition module problem, a coil problem, etc. Asking your mechanic to pull the no. 1 spark plug for a look-see at the electrodes might be a good idea. A plugged cat can cause stalling, but the symptoms of a clogged cat usually show up first as poor acceleration and sluggish high speed performance. It is possible for a mechanic to test the cat’s back-pressure, a measure of how much it is plugged, if the condition of the cat remains in question.

I guess if this were my car, the first thing I’d be inclined to do is update all the routine engine maintenance so everything is up to date according to what it says in the owners manual, then go from there. Best if your mechanic is equipped and trained to do a real time assessment of the ignition system, and has access to the Nissan scan tool.

Hello to all who have replied to me…
There are a few engine codes that I have had in chronological order
(1) P0442 - small evap leak dt 07/09/2012
(2) P0301 - engine cylinder 1 misfire dt 11/01/2012
(3) P0420 - cat effcy code dt 12/19/2013
(4) P0420 - cat system insufficent (below threshold) dt 02/14/2014
(5) P0340 - cam shaft position sensor dt 02/14/2014.
I purchased this car in Aug 2011 but in May 2011 cam shaft position sensor had already been diagnosed and replaced. Further, before I purchased there have been some repairs - in Oct 2009 cylinder head has been resurfaced and gaskets changed along with spark plugs, radiator coolant, hoses and thermostat. Struts and springs have been replaced too.
Since I have the car I have had work done on tires (alignment, rebalance/rotate, tires replaced, etc), battery replaced, both serpentine belts replaced, lots of brakes work done alongwith regular oil changes done. It has passed roadside emissions tests very well.
The problem of stalling still exists and, as you can see, a lot work has been done on this vehicle.
Is there something more that needs to be done? Are camshaft position sensor and crankshaft position sensor different? What is Obd2 connector, which may be broken? I am not a mechanic or mechanically inclined person either. And do not want to put a lot of money on this old car, which has 152000 miles currently. However, the car runs smoothly when the problems do not show up…
can it be water contamination in the gas? how can I have fuel pump, injectors cleaned up? is the air filter worth replacing? I would like keep the car for some more time.
Thanks guys.

@Sudhi

In my opinion, there’s no way the OBD2 connector (the 16in datalink connector under the left side of the dash) is broken

You would have failed any and all emissions tests were it broken

I don’t know where you got that idea in the first place . . .

“Is the air filter worth replacing?”

What kind of question is that? An air filter is a basic maintenance item . . .

“how can I have fuel pump, injectors cleaned up?”

Fuel injectors can be cleaned by hooking up cleaner to the fuel rail. Pumps are replaced if faulty

The cam and crank sensors are different

you say you spent a lot of money . . . yeah, you did

but here’s my take on it . . . most of those items you listed were maintenance and/or wear and tear

As the others have said, that #1 misfire quite possibly caused the p0420 cat code

As for the cam sensor code, a few possibilities come to mind . . . bad sensor, wiring problem, or your cam timing is off

As for the evap codes, those are sometimes difficult to diagnose. You need to find a very experienced mechanic who has brains, patience, an evap/smoke machine, and access to factory technical service bulletins and trouble trees for your car

Hi
It seemed like I have been silent…NO…I have replaced the sparks and the camshaft sensor and had the codes cleared. But the code P0420 has reappeared. However, my car has not stalled after the repairs. Could it be O2 sensor? I believe there are two of these - one on the engine and the other with the cat converter. Which one is more likely to be a problem? Acceleration is not very good but that maybe just the way I drive and it is OK with me driving mostly in the city.
Any more ideas? Suggestions and comments have been very useful. Thanks.

You could have a lazy o2. There are 2, one before and one after the cat. The back pressure can be tested on the cat. It can cause low performance.

Has all the routine engine maintenance been brought up to date? Does your mechanic have the Nissan scan tool and been trained in its use? Has the cat back pressure been tested?