For fooks sake its 2 steps forward and 3 back!

Thanks Ragtag, that great!!!!!!!!!!!!!

wammers,you mean for coolant or fuel?

fett said:

Thanks Ragtag, that great!!!!!!!!!!!!!

wammers,you mean for coolant or fuel?

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There is only one ECU engine temp sensor. Normally blue in colour, it controls the fueling according to engine temp. Turns choke on when cold and off when hot. Also in conjuntion with inlet air temp sensor adjusts fueling for air mass. If the engine starts, then when warm starts to play up i would think there is a strong chance it could be the ECU engine temp sensor that is faulty.

I agree but there is a fuel temp sensor on the front of the fuel rail on the 3.9 too.

As I said the collant one was new but it is a landover so I will have a look at that!

fett said:

I agree but there is a fuel temp sensor on the front of the fuel rail on the 3.9 too.

As I said the collant one was new but it is a landover so I will have a look at that!

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Which coolant one is new, the blue ECU temp sensor or the brown dash temp gauge sensor which has nothing to do with how engine runs. The fuel temp sensor tells the engine ECU the fuel temp because when fuel is cold, like air it is more dense and does not need as much injecting. The inlet air temp sensor along with fuel temp sensor and ECU engine temp
sensor adjust fueling to suit cold thick/warm thin air at the various temps the engine runs at.

ECU Coolant sensor new.

ECU fuel temp sensor not new.

Where is the air temp sensor ? inside the AFM?

Ok tried replacement , fuel temp sensor, coolant temp sensor, AFM and stepper plus all the other stuff listed before.

The only thing left to try is a working amp and an ecu (the latter I dont have)

The idle is way too low too!

BTW thanks for the bits Chris , I will keep you posted!

Hey, no probs although it doesn't sound like any of them were the 'magic bullet'.

Hopefully Stuart will be able to do his thang and get you running again........other than that you could always convert to those SU's you're getting

Nice to meet you BTW

Cheers

Chris

Good to meet you mate!

I am going to try the amp 2nite on the off chance, as the delivery of my two new classics was delayed by a broken down delivery truck :doh:

well I have just tried swapping out the amp , third time in as many days as the first replacement didnt work at all.

No joy.

So as far as I can see that only leaves the ecu as the fault is exactly the same with all other components swapped out.

well stu is the man , came round and in an hour had it running better than it ever has.

it was the throttle position switch , changed it out and tuned and timed it up and its runningh great!

Thanks Stuart!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

wammers said:

There is only one ECU engine temp sensor. Normally blue in colour, it controls the fueling according to engine temp. Turns choke on when cold and off when hot. Also in conjuntion with inlet air temp sensor adjusts fueling for air mass. If the engine starts, then when warm starts to play up i would think there is a strong chance it could be the ECU engine temp sensor that is faulty.

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Hot wire injection on 14 CUX ecu doesn't work quite like that. The engine temp thermistor does indeed tell the ecu if the engine is hot or cold to adjust the fuelling within the parameters of the fixed fuel map. The 14CUX is not an adaptive ecu although when running with cats it will use lambda input to more closely control fuelling in puruit of lower emissions. BUT it also looks at the fuel temp thermistor to determine if start enrichment is necessary whether cat or non-cat.

As far as I know there is not an inlet air temperature sensor. The hot wire air flow meter has a heating wire and an compensating wire and it is these that are used to provide a signal to the ecu to alter the injection pulse.

BTW Fett, glad you got your Rangie running sweetly, would have thought you would have checked readings from throttle pot, 'tis easy all you need is a volt meter.

as i didnt have a spare i was working through the parts i had first,thankfully stu had one with him!

two things i would look at, one check for water in fuel. pump some through the system and collect it in a clear jar and let it settle for a minute or two Water sits on the bottom and looks like a clear bubble.
the other is a blocked breather on the tank. easy check is do a test drive with fuel cap open.

Thanks mate but its sorted

classic kev said:

Hot wire injection on 14 CUX ecu doesn't work quite like that. The engine temp thermistor does indeed tell the ecu if the engine is hot or cold to adjust the fuelling within the parameters of the fixed fuel map. The 14CUX is not an adaptive ecu although when running with cats it will use lambda input to more closely control fuelling in puruit of lower emissions. BUT it also looks at the fuel temp thermistor to determine if start enrichment is necessary whether cat or non-cat.

As far as I know there is not an inlet air temperature sensor. The hot wire air flow meter has a heating wire and an compensating wire and it is these that are used to provide a signal to the ecu to alter the injection pulse.

BTW Fett, glad you got your Rangie running sweetly, would have thought you would have checked readings from throttle pot, 'tis easy all you need is a volt meter.

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Think the hot wire system is the inlet air temp sender. Without an inlet air temp sensor the fueling would be all over the place on a hot thin air day and totally different on a cold damp heavy air day. Air volume and mass measurement is critical to maintaining correct mixture.

According to Rave, there is no Inlet Air Temperature sensing on the Classic but there is on the P38s. However, on the GEMS, it's only used to compensate for high anmbient (above 55C!) temperatures by retarding the ignition. THOR does a bit more with it.
Hot wire elements are self compensating for temperature and density. Temperature is done via the comensating wire which is a thermistor. Density (due to temperature or ambient pressure) is self compensating by dint of the denser the air is, the more cooling effect it will have on the wire and so giving the effect of more air going into the engine. i.e. The wire measures the cooling effect of the air passing it which in turn is dependant on velocity and density. Make sense? I know what I mean, I'm just not very good at articulating it. There are others on here much better at it than I am.

thanks for a intresting time again fett!! glad to help.
right to put you guys straight
hotwire works this way
coolant temp, throttle position, vehicle speed, engine speed signal from dissy, afm signal and that is it!
as the air is drawn into the engine it cools the wire in the afm with ecu increase the voltage to achive the reading it requires thus knowing how much air is being drawn in dictates how long the injectors stay open for simple!

So, does the compensating element/thermistor just balance it to set a base line from where the changes in temp due to airflow are measured?

vougese39 said:

hotwire works this way
coolant temp, throttle position, vehicle speed, engine speed signal from dissy, afm signal and that is it!
as the air is drawn into the engine it cools the wire in the afm with ecu increase the voltage to achive the reading it requires thus knowing how much air is being drawn in dictates how long the injectors stay open for simple!

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Amen! the hot wire (and the flapper) system is that simple.