Xantia economy and ECU question

[jgra1]

well.. a 500 mile overnight trip to Wales and back ..

all told 550 miles.. I put in 50 Litres of WVO and £10 of deisel (about 7.5l)

so economy was : 43.4 MPG average.. (Cost of 550 miles was £35)

It's worth noting that I normally run my poor old TD ragged this time I tried to not use throttle for all of the above miles...

Also, roads were 50% A-roads and about 50% Motorway. For the last 300 miles, car had 2 adults and about another 175 Kgs in the back... And included roads around Brecon etc...

not sure if an average of 43 is good, with car never exceeeding 70mph, tailwind yesterday, and very careful throttle.... but 225 Kgs extra after my 90kg is quite a bit....

any thoughts ?

Ps one other problem... twice in the journey power was temporarily lost, being replaced by the EM light but it got me home....

What does the TD EM light warn of? Fuel pressure?, senser on injector 3... TDC sensor...

John
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[PicassoPigeon]

When I had a problem with the engine light coming on and loss of power it was due to the fuel tank pick up being covered with dirt due to running on veg oil.
Its under the back seat, made my Xantia run loads better after a good clean.

gav425

[AndersDK]

43mpg on avarage with a rather heavy load is not bad, not at all.

On such a long trip the engine gets good and all-over working hot. This will show any weaknesses like a duff sensor.
Both sensors mentioned are wirewound coil pickup sensors, evidently sensitive to lognterm heat fatigue failures - the most common wirewound coil killer.

Its rather annoying just forking out the money for both sensors, not knowing which one was the failing one. You can however unscrew them, heat them in an oven (100-120degC), and then do a couple of ohm's reading while they cool off.
VERY often they will simply fail hot, or at least within a certain hot temp range.
Also carefully check all connections and cables involved.

[DickieG]

What does the TD EM light warn of? Fuel pressure?, senser on injector 3... TDC sensor...

Potentially all or any of them but impossible to say which one unless you get the ECU read. Luckily most generic code readers able to specifically read Citroën ECU's should suffice (not EOBD ones), my Sykes ACR 4 does a good job on my TD.

[jgra1]

thanks all

Gav yep that is definately on my list.. 6 months on oil and I haven't looked in there yet !