Posted: Nov 07 2007 at 10:25am | IP Logged
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I got a bad knock sensor computer read out on mine, but they couldn't tell me if the knock sensor was actually bad or if it just adjusted the timing last time I was pulling a load. On my 2000 3.3L the knock sensor is under neath the intake manifold. So it's a 3 second plug to pull out and replace, but to get to it, you have to remove the intake and other items in the way.
You should test your knock sensor before you order a new one to replace it. I seem to recall the way to test it is to run a multimeter from pin 64 to ground. Let me see if I can find the "official instructions." Ah. Found it.
Cheers,
:Isaac:
1 CHECK INPUT SIGNAL CIRCUIT-I
1. Turn ignition switch “OFF”.
2. Disconnect ECM harness connector.
3. Check resistance between ECM terminal 64 and engine ground.
NOTE:
It is necessary to use an ohmmeter which can measure more than 10 M Ω.
SEF704U
Resistance:
Approximately 500 - 620 k Ω [at 25°C (77°F)]
4. Also check harness for short to ground and short to power.
OK GO TO 5.
NG GO TO 2.
2 CHECK INPUT SIGNAL CIRCUIT-II
1. Disconnect knock sensor harness connector.
2. Check harness continuity between ECM terminal 64 and terminal 1.
SEF642W
Continuity should exist.
3. Also check harness for short to ground and short to power.
OK GO TO 4.
NG GO TO 3.
3 DETECT MALFUNCTIONING PART
Check the following.
Harness connector F37, F101
Harness for open or short between ECM and knock sensor
Repair open circuit or short to ground or short to power in harness or connectors.
4 CHECK KNOCK SENSOR
Refer to “Component Inspection”, EC-333. (pasted below)
OK or NG
OK GO TO 8.
NG Replace knock sensor.
5 RETIGHTEN GROUND SCREWS
Loose and retighten engine ground screws.
AEC640A
GO TO 6.
6 CHECK SHIELD CIRCUIT
1. Disconnect harness connectors F37, F101.
2. Check harness continuity between harness connector F37 and engine ground.
Continuity should exist.
3. Also check harness for short to ground and short to power.
OK or NG
OK GO TO 8.
NG GO TO 7.
7 DETECT MALFUNCTIONING PART
Check the following.
Harness connectors F37, F101
Joint connectors - 1
Harness for open or short between harness connector F37 and engine ground
Repair open circuit or short to ground or short to power in harness or connectors.
8 CHECK INTERMITTENT INCIDENT
Refer to “TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT”, EC-133.
INSPECTION END
Component Inspection
NEEC0182
KNOCK SENSOR
NEEC0182S01
Use an ohmmeter which can measure more than 10 MΩ.
1. Disconnect knock sensor harness connector.
2. Check resistance between terminal 2 and ground.
Resistance: 500 - 620 k Ω [at 25°C (77°F)]
CAUTION:
Do not use any knock sensors that have been dropped or
physically damaged. Use only new ones.
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