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'89 sierra 2500 6.2 diesel 33 code?


rockwood84
03-28-2009, 01:53 PM
i'm getting a 33 on the ses light[obd1] and don't have a manual to tell what the code is. anyone know what the code is for? thanks

duke350
03-28-2009, 10:24 PM
Code 33 MAP Sensor Signal Voltage High.

rockwood84
03-29-2009, 11:38 AM
Code 33 MAP Sensor Signal Voltage High.
thanks duke350, you wouldn't know where the map is located on this truck would you? thanks again

duke350
03-29-2009, 02:23 PM
I don't know much about diesels, but I would assume it would be on the intake. If it were me I would check napa or someplace online to see what it looks like then see if you can find it. This is what MOD has to say about it.

Manifold Absolute Pressure (MAP) Sensor
The MAP sensor measures changes in intake manifold pressure resulting from engine load and speed changes. A 5-volt reference signal is sent to the sensor from the ECM. This signal is modified by the resistance of the sensor and sent back to the ECM.
Sensor resistance changes with manifold pressure. Therfore, sensor output voltage to the ECM is a direct indication of manifold pressure. High voltage indicates a high pressure condition requiring more fuel while low voltage indicates a low pressure condition requiring less fuel. The ECM uses this information to control fuel delivery and ignition timing. A failure in the MAP sensor problem may set Code 33 or Code 34.

duke350
03-29-2009, 02:29 PM
I just looked into it a bit further and it says to check out the EGR. I have a flow chart for it, if you want it tell me where to email it.

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