QuestionQUESTION: I have had multiple codes at different times. 1st, had a crankshaft position sensor and knock sensor codes, repaired knock sensor connector, cleared codes and ran great for 3 days. Service Engine light came back on. New codes, knock sensor code and engine misfire code. I don't want to start throwing parts at it as it seems to run fine.
Any advice would be greatly apreciated.
ANSWER: Steve,
Replace the knock sensor first. Then, reset the code and see if a misfire code comes back. The knock sensor retards timing depending on the signal it sends. A high tech microphone sensing detonation. If this were defective, which from my experience they usually are, replace it and see how things go. If the misfire code comes back see if it is multiple cylinders or a specific one or two. If it is specific then replace the coils on those cylinders. Also, if you have not done so in say 30K miles, replace the sparkplugs.
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QUESTION: OK, replaced the knock sensor, cleared codes. Ran it at idle for 10 min. no fault. Put it in reverse to road test, 2 engine misfire codes, non specific. replaced spark plugs, cleared codes and drove all day. Next day, light on, crank position sensor fault returned. Changed crank sensor, ran one day, crank position fault returned. Checked harness, o.k. Is it possibly a timing chain issue?
AnswerSteve,
My bet would be the coils at this point. But, these are quite expensive so I would not say to purchase them until you check the ohms inpedence on the old ones. Get a digital volt / ohm meter and a Haynes Manual and follow the instructions and diagram for testing coils. It would be nice to check them when the engine is hot since the coils will give a better indication as to their condition. Electrical parts tend to check good at room temperature.
