Professional Automotive Advice

A P1000 code is designed to inform the driver the engine management system is not working to it's full potential. When in open loop, the powertrain management system is operating on a set of values predetermined by the factory. When the computer senses the engine has warmed up to normal temperature the system will go into closed loop which allows full engine management adjustments for optimum economy and performance.

Step 1 - If the engine thermostat has stuck open, the engine operating temperature stays too low, causing the computer to stay in open loop. The computer is now constantly waiting for the engine to heat up for closed loop computing. Learn more

Cooling System Thermostat

Step 2 - The powertrain computer relies on feedback information via the oxygen, mass air flow, throttle position, crankshaft position, coolant sensors etc. to operate, if one of these sensors becomes severely shorted it can cause the computer to stay in open loop, causing the code gathering to be incomplete. Learn more

Oxygen Sensor

Step 3 - If a fuel injector short circuits it can cause the engine to stall. If the engine is not running code gathering will be incomplete, which presents a P1000 code. Learn More

Fuel Injector

Step 4 - Once the faulty sensor or injector has been found, clear the codes to recheck the system. Learn more

Code Reader

Questions?

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