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[Kevin Wood]

Not quite Chilworth - I was a bit further South on the A272 but could have made a detour.

I think the code reader has got IPW confused with something else. IPW should be about 3ms at idle when warm.

10kg/h at idle is a little low. 12 or so would be typical. It only needs to be a little low before a 2.6 will start playing up, sadly, and I've seen symptoms of holding revs high before.

The O2 activity stopping indicates that the MAF sensor output has taken the mixture out of the range in which it will operate closed-loop, so I think it reinforces the MAF sensor theory.

I don't think a latte would have caused a problem. Very little of the engine ECU wiring enters the cabin.

Might be worth keeping an eye on the live data when on the move - see if anything goes haywire while turning corners, etc. Assistant in the passenger seat with a laptop?

[Andy H]

Slightly off topic........

The 2.2 cam sensor seems to have a failure mode that randomly screws up communications with other sensors hence giving fault codes for components that are perfectly OK. I assume that means that there is a communication bus (1 ware/i2c/CANbus or similar) that is shared amongst more than one sensor

The 2.6 & 3.2 are a similar vintage so I assume use a similar ECU.

MAF failure on the 2.6/3.2 seems less common than cam sensor failure on the 2.2 but I wonder if the MAF shares a bus with other sensors (hence can screw up other components if faulty)

[TheBoy]

Slightly off topic........

The 2.2 cam sensor seems to have a failure mode that randomly screws up communications with other sensors hence giving fault codes for components that are perfectly OK. I assume that means that there is a communication bus (1 ware/i2c/CANbus or similar) that is shared amongst more than one sensor

The 2.6 & 3.2 are a similar vintage so I assume use a similar ECU.

MAF failure on the 2.6/3.2 seems less common than cam sensor failure on the 2.2 but I wonder if the MAF shares a bus with other sensors (hence can screw up other components if faulty)

I think you are confusing sensors knocking out other sensors one a shared bus with the ECU's error handling routines, and other spurious things that happen before ECU can detect which sensor is giving a reading not to be trusted.

All sensors have dedicated wiring back to their associated ECU on the Omega. A quick glance at the schematics will confirm that.

[TheBoy]

I should add, thats the very reason not to go purely on fault codes, but look at the underlying live data.

[Andy H]

Slightly off topic........

The 2.2 cam sensor seems to have a failure mode that randomly screws up communications with other sensors hence giving fault codes for components that are perfectly OK. I assume that means that there is a communication bus (1 ware/i2c/CANbus or similar) that is shared amongst more than one sensor

The 2.6 & 3.2 are a similar vintage so I assume use a similar ECU.

MAF failure on the 2.6/3.2 seems less common than cam sensor failure on the 2.2 but I wonder if the MAF shares a bus with other sensors (hence can screw up other components if faulty)

I think you are confusing sensors knocking out other sensors one a shared bus with the ECU's error handling routines, and other spurious things that happen before ECU can detect which sensor is giving a reading not to be trusted.

All sensors have dedicated wiring back to their associated ECU on the Omega. A quick glance at the schematics will confirm that.

I wasn't suggesting that any sensors shared wiring back to the ECU. I agree that the behaviour is probably caused by poorly programmed  fault detection but it struck me that the symptoms were rather similar to the problems resulting when one faulty sensor causes intermittent errors on a shared data bus.

[TheBoy]

Slightly off topic........

The 2.2 cam sensor seems to have a failure mode that randomly screws up communications with other sensors hence giving fault codes for components that are perfectly OK. I assume that means that there is a communication bus (1 ware/i2c/CANbus or similar) that is shared amongst more than one sensor

The 2.6 & 3.2 are a similar vintage so I assume use a similar ECU.

MAF failure on the 2.6/3.2 seems less common than cam sensor failure on the 2.2 but I wonder if the MAF shares a bus with other sensors (hence can screw up other components if faulty)

I think you are confusing sensors knocking out other sensors one a shared bus with the ECU's error handling routines, and other spurious things that happen before ECU can detect which sensor is giving a reading not to be trusted.

All sensors have dedicated wiring back to their associated ECU on the Omega. A quick glance at the schematics will confirm that.

I wasn't suggesting that any sensors shared wiring back to the ECU. I agree that the behaviour is probably caused by poorly programmed  fault detection but it struck me that the symptoms were rather similar to the problems resulting when one faulty sensor causes intermittent errors on a shared data bus.

Sorry, I obviously misinterpreted the highlighted bit 

Makes no sense to have dedicated wiring to an ECU, then use an inter ECU shared bus system within that ECU. I've had a Bosch Motronic 2.8.3 apart serveral times, and it strikes me to be a simplistic (at a hardware level) system driven driven by a traditional microcontroller. The 2.6/3.2 Motronic 3.1.1, although I haven't had one apart, I would imagine to be an evolution of this.

As for 2.6/3.2 and 2.2 ECUs being simiilar, they have different heritages, and different evolution. Though both, of course, are little more than a simple fuel/spark mapping system, based on a handful of inputs. 2.2 (and the 2.0 before it) use a Simtec ECU, not the Motronic fitted to the V6.

Hope that makes sense?

[Ryzer]

im having exactly the same issues on my 2001 2.6 ended up leaving maf unplugged just for sanitys sake lasted two weeks of perfect running now its dead outsiide my house  one thing to remember never use carb cleaner on a maf fastest way to kill it try taking your live off your battery overnight to force ECU to update to new settings it may help also you were right with earthing points defo check these before you spend any more cash also make sure previous owner havnt tie wrapped wires leading to maf as it could be broken wire inside cable insulation hope this helps just all things iv had to check lol if you come up with a solution can you please let me know as im running out of hair to pull out good luck pal (excuse my typing fat fingers small keys on this phone ) 

[Andy H]

Slightly off topic........

The 2.2 cam sensor seems to have a failure mode that randomly screws up communications with other sensors hence giving fault codes for components that are perfectly OK. I assume that means that there is a communication bus (1 ware/i2c/CANbus or similar) that is shared amongst more than one sensor

The 2.6 & 3.2 are a similar vintage so I assume use a similar ECU.

MAF failure on the 2.6/3.2 seems less common than cam sensor failure on the 2.2 but I wonder if the MAF shares a bus with other sensors (hence can screw up other components if faulty)

I think you are confusing sensors knocking out other sensors one a shared bus with the ECU's error handling routines, and other spurious things that happen before ECU can detect which sensor is giving a reading not to be trusted.

All sensors have dedicated wiring back to their associated ECU on the Omega. A quick glance at the schematics will confirm that.

I wasn't suggesting that any sensors shared wiring back to the ECU. I agree that the behaviour is probably caused by poorly programmed  fault detection but it struck me that the symptoms were rather similar to the problems resulting when one faulty sensor causes intermittent errors on a shared data bus.

Sorry, I obviously misinterpreted the highlighted bit 

Makes no sense to have dedicated wiring to an ECU, then use an inter ECU shared bus system within that ECU. I've had a Bosch Motronic 2.8.3 apart serveral times, and it strikes me to be a simplistic (at a hardware level) system driven driven by a traditional microcontroller. The 2.6/3.2 Motronic 3.1.1, although I haven't had one apart, I would imagine to be an evolution of this.

As for 2.6/3.2 and 2.2 ECUs being simiilar, they have different heritages, and different evolution. Though both, of course, are little more than a simple fuel/spark mapping system, based on a handful of inputs. 2.2 (and the 2.0 before it) use a Simtec ECU, not the Motronic fitted to the V6.

Hope that makes sense?

Yes
Laziness on my part, I hadn't realised (hadn't bothered to check relevant page on forum ) that the ECUs had different heritage.
I still have a sneaky feeling that Simtec cut corners inside their ECU and did something at a hardware level that allows the cam-sensor to interfere with communications to other sensors

[bootzey]

Guys. Thanks for all your input.
Got the car warmed up today and plugged the MAF in and let her tick over...no problems. Then...
went for a quick drive with the scanner connected. Left turn fine, left turn fine, right turn fine, left turn fine, left turn fine then drove a third of a mile through the village...no plod about phew!
Stopped to make a U turn.....not fine. As I turned the steering wheel to the right she lost power and chugged home. As I was doing the U turn I had a quite look at the scanner and F/T was at 25% and the 02's were at 0.00, like they had been switched off!
Got home and let her tick over very roughly then held the revs at 2K, looked at the scanner...same as above.
Released the throttle...revs stayed high.
Turned the lights on...revs dropped abit.
Turned the A/C on revs dropped a bit more.
Turned the steering wheel....revs dropped to normal. Then:-
Released the steering wheel...revs higher.
Turned A/C off....revs higher
Turned lights off...revs abit higher still.
And so it went on for about 10 minutes with any combination or order that I cared to choose.
So, convinced that it had something to with the power steering, I had a look in that general area :
there's about 4 earth wires in a group with a single fixing to the body...look ok but have a grey colouring to them.
Had a bit of a fiddle around and WTF kin hell that hurt...I had burnt the fingerprints of 4 fingers (still in a bit of pain now!!).
I could smell my skin burning...I'm sort of thinking mmm this might be dangerous lol
Had a look under the battery shelf expecting to find something red hot, couldn't see anything that hot.
Tentitively put my hand in to touch something and there's a white bit of electronic kit in a bracket bolted to the body just under the battery, it has a red n blue wire and a red n white wire 1 at each end and was kelly brooke hot.
Had to go to sainsburys so switched the car off, put my fingers under a cold tap for 10 minutes.
Then checked this component just before I left...stone cold, as cold as my poxy fingers lol
Unplugged the MAF and went on my merry way.
Got home and checked this thing again expecting to burn the fingers of my right hand but....stone cold?
The only thing I had done was unplug the MAF.
What on earth is this white electrical thing under the bonnet??

[bootzey]

Chinese MAF turned the EML off immeadiately!!!
then when I shut the bonnet...i'd forgotten to put the drivers side windscreen wiper back down....snapped off! oh the joys of owning a car!