My range approx decreased 2 km on every half km. It showed check engine light than I have cleared all the codes (fuel injector - cleaned , replaceed all the oxygen sensor by new one than by changing the catalytic converter). Now there is no check engine light but after few days later mileage is dropping same problem. But still engine maintenance light is blinking. Please help me to solve this issue. (My mechanic says their can be a electrical issue

 

Range is an estimate based on your recent driving. If you have been thrashing the car then the range will drop faster. It is not a reliable indication of fuel consumption.
If you still have the Check Engine light but there are no codes, then you may have a problem with your ECU.
Have you tried a battery off reset? (disconnect battery for at least 15 minutes)

 

Thanks for replying, overall my mileage 22 liters for 100km and my engine maintenance light is blinking. I don't have check engine light. My mechanic told me, there can some electrical issue in my vehicle.

 

That is 10MpgUS which is terrible gas mileage. Should average about 21MpgUS.
You need to read the codes from the ODB2 port to get a clue as to the cause.

 

Wouldn't be surprised if there's a bad coil or two if you legitimately took out a cat converter.

 

A blinking check engine light usually means there are active misfires. Not sure what a blinking "engine maintenance light" is (the red triangle?)

Get a scantool, pull codes if any, examine everything relating to the engine ECU, including misfire counts, short-term and long-term fuel trims, O2 sensor waveforms/efficiency, air flow readings. By examining all parameters of the engine/air/fuel system while the car is running, you should be able to narrow down the cause of the problem.

 

Thanks, I don't have check engine light. Have changed my ecm, new spark plug and Maf. Unfortunately, after one day same problem raises. Range approx decreased 2km on every half km.
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