Checking and Replacing Knock Sensors

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The knock sensor is hidden way up underneath the intake manifold next to the engine block. Here's a step-by-step on how to replace it.

1. get a long extension for your socket wrench

2. get the adapter that allows for a few degrees of movemen (the knock sensor is only attached by one 17mm bolt)

3.get a long pair of needle-nose pliers 4. get a long rather stiff wire or plumber's snake

5. first disconnect the battery of course

6. disconnect two rubber fuel lines that block the space between the two middle intake runners and push aside. (you may have to relieve some fuel pressure)

7. disconnect the harness for the knock sensor, but before you go on, connect the plumber's snake (or wire) to the end of the harness that leads to the sensor under the intake manifold.

8. now unbolt the sensor

9. take the needle-nose pliers and reach down to pull out the sensor along with the wires. (try not to pull out the entire length of plumber's snake)

10. disconnect the old sensor and plug in the new one

11. Go ahead and thread the bolt through the sensor before you lower it back into its place. 12. wrap a thin piece of electrical tape around the head of the bolt as you insert it into the socket wrench, this helps keep the thing from slipping out of the socket as you lower everything back in. 13. as you steadily approach the engine block with sensor and bolt, pull out slack in wire with plumber's snake in the direction of respective harness 14. bolt down the sensor and reconnect the harness.

Contributed by: Anibal Betanzos


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