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For 1990-2009 cars only

Oil Pressure Gauge Appears Inaccurate P92

P92 Oil Pressure Gauge Appears Inaccurate

Step

Action

Value(s)

Yes

No

1

Does the oil pressure gauge read accurately?

--

System OK

Go to Step 2

2

Does the oil pressure gauge indicate high pressure at all times?

--

Go to Step 8

Go to Step 3

3

Does the oil pressure gauge indicate low pressure when oil pressure is good?

--

Go to Step 10

Go to Step 4

4

  1. Disconnect the engine coolant temperature sender connector.
  2. Connect the red lead of J 39200 to the WHT (15) wire at the oil pressure sender connector and the other lead to ground.
  3. Set the resistance dials to 0 ohms and then to 900 ohms.

Does the oil pressure gauge read low then high?

0 ohms (low)

900 ohms (high)

Go to Step 5

Go to Step 6

5

Replace the oil pressure sender.

Is the repair complete?

--

Go to Step 1

--

6

Locate an open in the WHT (15) wire between the oil pressure sender connector and the oil pressure gauge.

Is the WHT (15) wire open?

--

Go to Step 12

Go to Step 7

7

Replace the oil pressure gauge.

Is the repair complete?

--

Go to Step 1

--

8

  1. Disconnect the oil pressure sender connector.
  2. Place the ignition switch in RUN.
  3. Connect a fused jumper from the WHT (15) wire at the oil pressure sender connector to ground.

Does the oil pressure gauge indicate low or the oil pressure light come on?

--

Go to Step 5

Go to Step 9

9

Locate an open in the WHT (15) wire or in the indicator bulb.

Are the wire and the bulb OK?

--

Go to Step 7

Go to Step 13

10

  1. Disconnect the oil pressure sender connector.
  2. Place the ignition switch in RUN.

Does the oil pressure gauge indicate high pressure or the oil pressure indicator lamp go out?

--

Go to Step 5

Go to Step 11

11

Does the oil pressure gauge indicate low or no oil pressure or does the oil pressure indicator lamp come on?

--

Go to Step 6

Go to Step 1

12

Repair or replace the wire.

Is the repair complete?

--

Go to Step 1

--

13

Repair or replace the wire or the bulb as necessary.

Is the repair complete?

--

Go to Step 1

--

Oil Pressure Gauge Appears Inaccurate P72

P72 Oil Pressure Gauge Appears Inaccurate

Step

Action

Value(s)

Yes

No

1

Does the oil pressure gauge read accurately?

--

System OK

Go to Step 2

2

Does the oil pressure gauge indicate high pressure at all times?

--

Go to Step 8

Go to Step 3

3

Does the oil pressure gauge indicate low pressure when the oil pressure is good?

--

Go to Step 10

Go to Step 4

4

  1. Disconnect the oil pressure sender connector.
  2. Connect the red lead of J 39200 to the TAN (31) wire at the oil pressure sender connector.
  3. Connect the other lead to the ground.
  4. Set the resistance dials to 0 ohms and then to 900 ohms.

Does the oil pressure gauge read low then high?

0 ohms (low)

900 ohms (high)

Go to Step 5

Go to Step 6

5

Replace the oil pressure sender.

Is the repair complete?

--

Go to Step 1

--

6

Locate an open in the TAN (31) wire between the oil pressure sender connector and the oil pressure gauge.

Is the TAN (31) wire open?

--

Go to Step 12

Go to Step 7

7

Replace the oil pressure gauge.

Is the repair complete?

--

Go to Step 1

--

8

  1. Disconnect the oil pressure sender connector.
  2. Place the ignition switch in RUN.
  3. Connect a fused jumper from the TAN (31) wire at the oil pressure sender connector to the ground.

Does the oil pressure gauge indicate low or the oil pressure light come on?

--

Go to Step 5

Go to Step 9

9

Locate an open in the TAN (31) wire or in the indicator bulb.

Are the wire and the bulb OK?

--

Go to Step 7

Go to Step 13

10

  1. Disconnect the oil pressure sender connector.
  2. Place the ignition switch in RUN.

Does the oil pressure gauge indicate high pressure or the oil pressure indicator lamp go out?

--

Go to Step 5

Go to Step 11

11

Does the oil pressure gauge indicate low or no oil pressure or does the oil pressure indicator lamp come on?

--

Go to Step 6

Go to Step 1

12

Repair or replace the wire.

Is the repair complete?

--

Go to Step 1

--

13

Replace the wire or the bulb as necessary.

Is the repair complete?

--

Go to Step 1

--