I have a 2000 Nissan quest van the check engine light blinks on and off while driving what could be the problem
It may need servicing and is letting you know that it is nearing a pre programmed service interval. It may be that an issue is in the process of developing and is giving you notice of it. I would consult a good independent to have them check it out before anything serious develops
check engine light p0325 knock sensor bank 1 or sensor closed loop bank 1 p0135 o2 sensor i bought the car with check engine light on i 've changed on of the o2 sensor and i did tun up on it but still the light still the code in the scanner reading the code in the top
The PO325 knock sensor code is common on many Nissans, it doesn't bring on the Service Engine Soon if is performance related, it will bring on the light if the sensor goes open circuit.. These engines just always seem to have that code when you are presented with another trouble code, so go after the Oxygen Sensor related code first. The code P0135 is for the heater circuit control in the front O2 Sensor. If you still have the old O2 sensor check the electrical connector on the old sensor two of the wires should have continuity to each other (this is the heater circuit, if none of the wires at the connector have continuity the sensor is in fact defective but they sometimes go "open only when hot operating conditions). The electrical harness itself gives problems and failure occurs bringing on the Service Engine Soon light. Ignition key on you should have power (12V) at the disconnected O2 sensor harness. The computer grounds the sensor heater circuit as required. The problem may have to be fixed by "ohming" out the harness wires until the fault is found. I suspect by fixing the P0135 problem your service light will stay out once reset. The knock sensor is labor intensive to replace.
most check engine lights come on and stay on but, yours may have a warning flicker first--USUALLY it is just a pain the butt light that makes you bring it to the dealer,,,they are set at mileage intervals and when dealership or whomever replaces oil they RESET IT,,,but--if you want to try resetting it yourself (wont hurt anything-if it is something real will come on again after resetting it) Here is what you do... turn car off,,,press and hold TRIP reset if you have one and turn car to the position JUST BEFORE the start position and keep holding... you should see lights come on and then one by one go off OR your trip will have a series of dashes that decrease till there is none left... thats it ! if this does work and it is something wrong it will come back on,,,,in which case bring it to autozone or autostore and they will hook up the diagnostic and tell you for free what is bothering your car.
There are literally about 150 reasons why the check engine light could come on. Did the mechanic read the codes? It sounds like he is guessing at reasons. A blinking check engine light is the "second level" of check engine lights. If the light comes on, there is a problem, but if it blinks, there is a problem that immediately needs to be addressed or you risk damaging the catalytic convertor or other components. A leaky intake gasket is possible but I would consider other options first, like a throttle position sensor or 02 sensor.
