This is more commonly called a Long Term Fuel Trim (LTFT) error.
The lambda sensor constantly checks the exhaust gas while the engine is running.
It tells the Engine Management Unit (cars computer) if the exhaust gas is showing a lean (too little fuel, too much air) or rich (too much fuel, too little air) condition. The E.M.U then alters the amount of fuel being injected into the engine. This is fuel correction management.
However, the ECU also compares the amount of fuel injected against a basic setting. If the lambda sensor tries to adjust the fuelling beyond a certain percentage then the E.M.U will assume something is wrong and throw a code. This is Fuel correction management error.
Common causes of this are faulty lambda sensor or faulty air flow sensor.
A competent diagnostics tech should be able to use Live Data to look at what all the sensors are reading.
Basically, clear the fault code(s), check the LTFT has reset, run engine up to normal operating temp, check the air flow meter is showing a plausible reading and that the lambda is switching from rich to lean and back about once per second.
There are other possible causes, but they are the usual suspects.
A faulty sensor will not always set its own fault code, if it is still sending a signal of some sort to the EMU, the EMU cannot tell if it is incorrect. If the tech tells you these parts must be OK simply because your car is not reading a fault code for them then you need to find a better tech.
If fitting new lambda or air sensor please spend the extra money and buy proper Vauxhall parts, cheap copy parts off the auction sites are usually not very good.
grilla
August 2011
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