My corolla, when warmed up cuts in and out when driving, each time it cuts in and out the check engine lights comes on then goes away as it cuts back in.. (its the same as if it was missing, except its not missing )
$900 debt from electrical / mechanical fee's for them to replace useless crap eg - dizzy, fuel filter, leads, coil, etc etc etc.
So, i done a diagnosis check..
It flashes once.. follow by 3 in a row after a few second break, im guessing this is 13 or 31..
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13 RPM Signal
Diagnosis
* No "NE" signal to ECU when engine speed is about 1,000 RPM.
Trouble Area
* Distributor, or CPS, circuit
* Distributor or CPS
* ECU
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31 Air Flow Meter Signal
Diagnosis
* (7M-GE) Open circuit in VC signal or short circuit between VS and E2 when idle contacts are closed.
* (7M-GTE) Open or short circuit in air flow meter signal.
Trouble Area
* Air flow meter circuit
* Air flow meter
* ECU
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What do both of these mean and what should i check?? Is it 31 or 13

Thanks, i just need help clearing up what error it is and what it means i should do.