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[RossMk2]

..what should it be trying to do differently than when warm as to idle?

Dont want to go into problems (again) as i want to go to war tomorrow with it and see what i can see. Just wonder what is involved with idle at cold thats different to when warm.

[Kevin Wood]

Main differences are that some enrichment will be applied when cold and, perhaps more significantly, the engine will be running "open loop" (fuelling controlled solely by measured airflow into the MAF) rather than "closed loop" where the inputs from the Lambda sensors are used to adjust the fuelling.

Kevin

[RossMk2]

Ahhhh thanks kevin! So i need to be looking weither its not putting more fuel in when cold! Does pop violently down the exhaust when cold which usually means leaning out right?

[Kevin Wood]

Sounds like it might be lean. MAF sensor would be a suspicion of mine, especially if it's the newer 2.6 / 3.2 variant. Needs more diagnosis to be sure but if it's reading low the mixture is well lean, and it gets corrected when the Lambdas start working.

Could also be coolant temperature sensor always reading hot, I guess. :-/

A Tech2 would confirm.

Kevin

[RossMk2]

Its the early X30XE. No faults using "My Naff Code Reader" coming from the MAF, what kind of figure should i see from the reading from it?

Coolant temp sensor is new also.

[Kevin Wood]

Not sure on the X30XE. Normally about 12-14kg/h on the 3.2 when idling hot. Not sure if it's displayed as kg/h or just a voltage though?

Is live data showing coolant temperature correctly?

Does it show the fuel trim / block learn values? If so are these straying far from their nominal value (128)?

Kevin

[Omegafantasy]

Does it show the fuel trim / block learn values? If so are these straying far from their nominal value (128)?

Kevin, I just wondered; what is acceptable values here? My values range from 116 to 131 (idling).

[RossMk2]

Not sure on the X30XE. Normally about 12-14kg/h on the 3.2 when idling hot. Not sure if it's displayed as kg/h or just a voltage though?

Is live data showing coolant temperature correctly?

Does it show the fuel trim / block learn values? If so are these straying far from their nominal value (128)?

Kevin

It has a reading for both kg and volt. From memory this morning it was 19kg/h i think, cts is working correctly.

One thing i did notice was the dsesired idle air was way high, in the 50's kg/h! Cant remember what the block learn value was of the actual MAF, that is what you were asking right as i see block learn for O2 sensors & idle, didnt catch one for maf mind.

And you are correct as to the fact it idles ok soon as the O2 sensors go to closed loop.

[Kevin Wood]

Sorry - it was the block learn for the O2 loop I was talking about.

19kg sounds high if it's idling at the correct speed (400-600 RPM) and up to temperature,

Kevin