I have had the timing belt and kit replaced on my car along with a sensor and my check engine light will not go off so that i can pass the required emissions test for my state

Ah the old 'Let's try replacing this' method of car repair. It doesn't work and is expensive.

The Yellow OBD (on board diagnostics) Light is telling you there is a problem and if you connect a Professional Grade Scan Tool Computer, it will give codes and tell you exactly what the problem is. You can't guess, you need a mobile auto electrician.

https://www.google.com/search?q=auto+electrician+near+me

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it is probably really old and it probably just has malfunctioned

That is a good question but the answer is POSSIBLE but generally NO... and I will explain why

O2 Sensors read the amount of Unburned fuel in the Exhaust and sends the readings back to the Computer. So the computer gets the readings from BEFORE and AFTER the Catalytic converter and "METERS" the amount of fuel it puts into the engine.

The Timing Belt is what keeps the CRANKSHAFT and CAMSHAFT in perfect harmony so that Valves open and Close at the right time. Spark Plugs are firing the Fuel at precisely the right time... All the Orchestra is done by the Timing Belt.

Now, if the Timing Belt was installed improperly (which is VERY EASY TO DO), you would notice a slight sluggish or poorly running engine. Your engine will run being 2-3 teeth off. But you would notice it being off by the way it runs

So can it effect the O2 Sensor? It could but not normally if your car is running properly

code p 0340 refers to camshaft position sensor(CMP) sensor A bank 1---circuit malfunction===causes ---wiring---CMP sensor ECM
have the CMP sensor checked / replaced
when you are checking the sensor , turn the engine over and if the camshaft is turning , it is not a timing belt
However if the engine has not had a timing belt changed (requirement at 60K miles) It would be a good move to have it done as it is well over due and will fail soon

If they only replace the crank sensor the timing belt will be removed along with the other belts on the front of the engine so if any of the belts are worn it is a good time to replace them. With a $1275 estimate I suspect that other work is to be performed at the same time though.



The sensor list price is $80 and the time required to replace is 3.0 hours so at $100 per hour labor and 1 hour to diagnose it the charge should be $480 plus shop fees and taxes.

Have you ever replaced the timing belt?? If not the problem is likely to be a loose worn out timing belt. A floppy belt will play havoc with the sensor signals and trigger a check engine light and a camshaft sensor code.

make sure there is not a evedent eng. noise 1st

hi to be honest...no these have a mileage limit that they advise you to change them, but most people do it before this time there is no warning as to when they will go, if you are unsure, and if it has done 60,000 miles + then i would change it to be on the safe side..and this will be an emissions fault, it will more than likely be one of the o2 sensors on the exhaust..but the error code should tell you what it is exactly...hope this helps

Is it running rough? Is the check engine light on?

was the timing belt changed, since it overheated the cam may have gotten tight and the belt might have jumped 2-3 teeth and you still would have a spark and fuel pressure.