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Old 29th November 2019, 15:34   #21
pletevl
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Following this :-)

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Old 29th November 2019, 16:04   #22
Sheraton
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Ok, due to work and life getting in the way, I haven't had chance to MOT it until today. Failed again. CO 11.68 - 12.25%, HC 986-992ppm.
Work done ;- new MAP, new injectors (MGR originals), intake resealed, new purge valve (old one snapped), MAP wiring replaced, comp test (all OK), new lambda, new manicat, new temp sensor.

Something is making it overfuel and I don't know what. Its got to the point I MUST find out why now, one way or another.
Any ideas? Could the throttle pot make that much difference?? ECU failure??


Sounds like the Lambda Control is stuck in an Open Loop - causing Overfuelling.


A Good run where you can cruise steadily for 5-10 mins at constant 55-65 mph - followed by some start stop driving in town should be enough for the IM Monitors to be ready and allow the Lambda Control to function in a Closed Loop state - and properly control Fuelling.

Not easy without an MOT tho

from what i'm aware - clearing Fault Codes resets the IM Monitor readiness and will require the Car to be Run through certain Load/Speed/Temp conditions etc.. before the IM Monitors will be in a Ready state.



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Old 29th November 2019, 16:09   #23
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Quote:
Originally Posted by Sheraton View Post
Sounds like the Lambda Control is stuck in an Open Loop - causing Overfuelling.


A Good run where you can cruise steadily for 5-10 mins at constant 55-65 mph - followed by some start stop driving in town should be enough for the IM Monitors to be ready and allow the Lambda Control to function in a Closed Loop state - and properly control Fuelling.

Not easy without an MOT tho

from what i'm aware - clearing Fault Codes resets the IM Monitor readiness and will require the Car to be Run through certain Load/Speed/Temp conditions etc.. before the IM Monitors will be in a Ready state.



Paul.
I have tried that before; I have had a suggestion from one of this parish to check the timing - that is on the 'to do' list as long as it doesn't p*ss down over the next few days....
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Gerry T, Rad Fan Resistor, Handbrake Compensator, Bonnet Catch Block, Leather Handbrake gaiter, Journey Camera,
Sean's DD Unit with Freeview!, Towbar, Rear Sunblind, Smiley!, Headlamp Protectors, Alloy Intake, R75 Brolly, Puddle lights, reversing camera.


2006 MG ZTT 160+ cdti auto; for disposal.


2004 Connie CDTi Tourer; replacement for the ZTT.
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Old 29th November 2019, 16:24   #24
Sheraton
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I have tried that before; I have had a suggestion from one of this parish to check the timing - that is on the 'to do' list as long as it doesn't p*ss down over the next few days....


A timing issue actually may be more likely - IM Readiness can be checked with a Diagnostic Tool/Reader - I see you have attempted diagnosis with the MOT Station, surely they'd have noticed if the IM Monitors were Not Ready.



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Old 29th November 2019, 17:10   #25
Shapfell
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A timing issue actually may be more likely - IM Readiness can be checked with a Diagnostic Tool/Reader - I see you have attempted diagnosis with the MOT Station, surely they'd have noticed if the IM Monitors were Not Ready.
Paul.

Aye, and Trikey has had it on T4 several times with nothing blatantly obvious.
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Work so far:-
Gerry T, Rad Fan Resistor, Handbrake Compensator, Bonnet Catch Block, Leather Handbrake gaiter, Journey Camera,
Sean's DD Unit with Freeview!, Towbar, Rear Sunblind, Smiley!, Headlamp Protectors, Alloy Intake, R75 Brolly, Puddle lights, reversing camera.


2006 MG ZTT 160+ cdti auto; for disposal.


2004 Connie CDTi Tourer; replacement for the ZTT.
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Old 29th November 2019, 18:43   #26
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Aye, and Trikey has had it on T4 several times with nothing blatantly obvious.
Just scrap it Mike, I'm sure a Marina is exactly what you need instead........the "Empress" in fact


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Old 29th November 2019, 18:57   #27
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If it were me, I would go to a different petrol station and use a different ron fuel, and then use a different MOT test station. You never know???
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Old 29th November 2019, 22:31   #28
Shapfell
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Just scrap it Mike, I'm sure a Marina is exactly what you need instead........the "Empress" in fact


Brian
If only, mate. She got scrapped in the late '90's, sadly, with terminal rot.
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2004 Conn SE 1.8
Work so far:-
Gerry T, Rad Fan Resistor, Handbrake Compensator, Bonnet Catch Block, Leather Handbrake gaiter, Journey Camera,
Sean's DD Unit with Freeview!, Towbar, Rear Sunblind, Smiley!, Headlamp Protectors, Alloy Intake, R75 Brolly, Puddle lights, reversing camera.


2006 MG ZTT 160+ cdti auto; for disposal.


2004 Connie CDTi Tourer; replacement for the ZTT.
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Old 18th December 2019, 20:35   #29
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Okay, tried again yesterday. Still nearly 12%....FFS.
Would a failed carbon canister cause this when the purge valve opens by drawing fuel vapour straight from the tank?
Do the 1.8 n/a 75's have a fuel return line from the pressure damper? Seems daft if they don't but haven't been able to find anything concrete as toi whether they do or don't...
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Oh well, it's only money......

2004 Conn SE 1.8
Work so far:-
Gerry T, Rad Fan Resistor, Handbrake Compensator, Bonnet Catch Block, Leather Handbrake gaiter, Journey Camera,
Sean's DD Unit with Freeview!, Towbar, Rear Sunblind, Smiley!, Headlamp Protectors, Alloy Intake, R75 Brolly, Puddle lights, reversing camera.


2006 MG ZTT 160+ cdti auto; for disposal.


2004 Connie CDTi Tourer; replacement for the ZTT.
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Old 7th January 2020, 15:26   #30
Shapfell
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At the end of my tether today. Failed again, still the same, 12% or thereabouts CO.
So, going through the list of checked/replaced;
Air filter
Injectors
Inlet manifold gaskets (alloy type fitted)
Fuel rail damper (although I haven't a clue why its fitted to a 1.8 n/a as there is no return line)
Manicat
Both O2 sensors
Plugs
Coil packs
MAP
T4'd several times with nothing obvious (thanks Trikey!)
Compression test ok @ approx 13b
No overheating
No coolant loss
Oil 'clean' (ok, its mucky but uncontaminated).


So, tried a CO2 test on the coolant - failed. Oh FFS! I had done this before but it showed nothing and passed.
Now trying to decide what to do.... would an N series drop in there (MGTF, not MG6 variant)?
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Oh well, it's only money......

2004 Conn SE 1.8
Work so far:-
Gerry T, Rad Fan Resistor, Handbrake Compensator, Bonnet Catch Block, Leather Handbrake gaiter, Journey Camera,
Sean's DD Unit with Freeview!, Towbar, Rear Sunblind, Smiley!, Headlamp Protectors, Alloy Intake, R75 Brolly, Puddle lights, reversing camera.


2006 MG ZTT 160+ cdti auto; for disposal.


2004 Connie CDTi Tourer; replacement for the ZTT.
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