V6 Gdi Only Running On 3 Cylinders. Help! Options

[bekker]

Hi guys

Wife was out yesterday and reports car spluttering, nearly stalling and very low on power. Manages to get it home and after a short drive I confirm!

Car: 2000 Chariot Grandis V6 GDi.
129000 km

So, I'm in the early stages of diagnosing the problem. So far I have...

- Checked the coils for spark - all are sparking.

Here is the weird thing, when I unplug any of the three coils along the front of the engine there is no change. Unplug any of the three rear bank coils and the engine nearly dies.

So the engine is running on the rear three cylinders only??

What could be causing this? Could it still be an electrical fault, such as the Fuel Pressure Sensor? I've heard these go bad relatively often, but would that cause all three cylinders to stop woking at the same time? The rear three cylinders are closest to the high pressure pump, so if the sensor was sending a poor signal, could there be just enough pressure for the first bank on cylinders?

Economy is very poor - computer telling me 3.5 km per litre.

Like I say, early stages of diagnosis, so any and all suggestions appreciated.

The engine otherwise runs very sweetly.

Cheers

Rohan