156 v6 with asthma and a cough
80% of the time the car drives OK, but when pushed seems to lack power but runs smooth enough.
At times though, usually at lower speed and revs it will cough and splutter and nearly stop but doesn't stall. Then all of a sudden the power will return and I'll get thrown into the back seat.
The fault seems to affect several cylinders at once, so total is the loss of power.
I've cleaned out the fuel filter, run injector cleaner and a tank of 98 octane E10 to eliminate water.
The lambda sensor had an o/c heater coil - but changing it for a new one change the symptom anything apart from clearing the stored error code. No other codes were stored and I replaced the MAF on spec' with a new one after cleaning it got no improvement.
I've checked and cleaned the injector relay, all good. All of the injector, MAF and throttle body connectors have been checked and cleaned.
Any serious suggestions are welcome.