QuestionQUESTION: i bought a 2003 Hyundai santa fe with 106000miles on it. but started with running for few miles then goes off. will not start until you let it cool for some minutes. we changed the fuel pump, cam shaft position sensor. it worked well for few weeks and then started again, this time the mechanic is saying crankshaft position sensor. What might actually be the cause of this problem.
ANSWER: The crankshaft position sensor may be the cause. Especially on the 2.7L V6 engine, the wire insulation on the crank sensor has a habit of cracking off and allowing the wires to short together. Without receiving signal from the crankshaft position sensor, the engine control module cannot determine when to fire the spark plugs and injectors.
While I obviously cannot do this over the internet, the best way to diagnose this problem is for the shop to let the vehicle run until it stalls. The shop should then be able to figure out what necessary ingredient for the engine to remain running may be missing.
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QUESTION: It's a 4 cylinder engine, and i was made to understand that this crankshaft has equally been changed, so why is it still failing. Thanks for this is a good advice so i can follow up with the workshop.
AnswerThis is a difficult question to answer. If it seems that the crankshaft position sensor was the issue, and this sensor was replaced with no change in the vehicle's behavior, then it's typically a safe assumption that the crank sensor isn't the issue.
So, this leads me back to asking about basics.
1. Has the engine lamp been coming on? If so, did anyone read the diagnostic trouble codes? If so, what were they?
2. If the ignition is turned to the on position when the problem is occurring, does the check engine lamp illuminate?
3. Do you have spark when the problem is occurring?
4. What is the fuel pressure when the problem is occurring?
5. Is the camshaft timing correct?
