QuestionQUESTION: Hi I have a 2000 Sonata with a 2.5 eng. The other day while
driving the car started to miss and run rough. It set a fault PO335, then seemed to correct its self. I replaced the crankshaft position sensor. Now I cannot get the car to come off idle. It is like the computer is trying. Flux. between 1000 to 500 RPM. and code PO335 steady light. Did I put a bad sensor in? Help?
ANSWER: Was there an o-ring on the old sensor when you removed it? If not, chances are it's still in the hole in the engine and you now have two o-rings there, preventing the crankshaft position sensor from operating normally.
To be sure the computer thinks you still have a crank sensor issue, disconnect the battery for 5 seconds to clear the code, and then restart the engine. If the computer believes the issue to be with the crank sensor, you should set a pending P0335 or P1372 on the first start and it should become a stored code on the second start.
Did the old crank sensor have any phyiscal damage to the end that was in the engine? If so, that's an indication that the wheel on the crankshaft is coming loose or is otherwise damaged.
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QUESTION: Hi Thanks for the quick come back. Yes the o-ring was on the old sensor when removed. I have cleared the computer codes by disconnecting the battery and using my scanner and the code continues to come up PO335. And yes the old sensor had external damage nothing internal. Thanks again
AnswerUnplug the crank sensor, turn the ignition key on, and check for battery voltage between the terminals in either end of the harness connector. You should have power in the pink wire and ground through the ECM in the black/white wire. If that's okay, you'll next need to check the wiring between the sensor and ECM. For that, I'll direct you to the Hyundai service website, since you'll need information from the schematic to see which wire to check.
The Hyundai service website is www.hmaservice.com (requires Internet Explorer). Once you've registered for a free account, go to the ETM section and select the appropriate fuel system schematic. The schematic will give you a diagram with connector numbers, connector pin numbers, and wire colors. You can also, through the links at the bottom of the schematic, see pictures/drawings of component and connector locations.
If all the wiring checks okay, I'd suspect that the sensor is defective or you have a problem in your ECM. If you're leaning in the ECM direction, you should probably have the car professionally diagnosed for two reasons. First, ECMs rarely fail on your year and model vehicle. Second, ECMs are expensive. You don't want to replace one if it's not the problem.
