MAP Sensor Installation

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Wiring in a replacement MAP Sensor

 

If wiring in a replacement MAP sensor take great care to ensure that the wiring is correct before applying power. Most MAP sensors will not tolerate reversed polarity and will burn out very quickly.

 

To save cutting the wiring harness it is recommended to use a replacement MAP sensor with a Honda type connector. Failing that, use a MAP sensor with wiring pigtail and wire the MAP sensor in parallel with the stock MAP connector (only plug in one MAP sensor at a time!). This allows easy diagnostics of any problems by allowing the stock MAP sensor to be hooked up at any time. It is not recommended to cut the stock MAP sensor connector off.

 

Stock MAP Wiring

 

Wire Color

Function

MAP Marking

yel/red

VCC

V

grn/red

MAP Signal

O

grn/wht

GND

G

 

Determine the replacement MAP sensor wiring and splice the wiring into the factor harness. Double check all connectors before switching the ignition on as most MAP sensors will burn out if you make a wiring mistake.

 

Plumbing in the MAP sensor

 

Run a vacuum line from the intake manifold for the MAP sensor. The MAP sensor must read the intake manifold pressure accurately.

 

For supercharged vehicles make sure that the MAP sensor is connected to the intake manifold after the supercharger, otherwise it will not see boost.
Do not be tempted to use the cold air bypass fitting close to the cylinder head between number 2 and 3 cylinders. This supplies air to the injector tips while cold for better emissions and is a poor place to read manifold vacuum.
Run a single vacuum line from the manifold to the MAP sensor with no 'Ts' or branches to other devices, such as blow of valves, boost gauges and boost controllers.