Vauxhall Astra H - astra cdti fuel problem

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Tue 24 Jan 2017 21:37
Vauxhall Astra H - astra cdti fuel problem - frogmarch

Hi I have posted before about my astra 1.9 cdti120 but is still using a lot of diesel , I have cleaned egr but not tried replacing glowplugs yet , I put tenners worh of diesel in and trip on speedo said I had done 52 miles and the computer said I was getting average of 36.9 mpg , it was mostly town driving and one or two trips of 20 mile round trips , do not know what else to try .only codes coming up is p0380 glowplug error , any help would be appreciated thanks

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Wed 25 Jan 2017 08:51
Vauxhall Astra H - astra cdti fuel problem - hardway

Glow plugs pretty much ONLY used for starting from cold,

nothing to do with MPG.

Get it scanned for fault codes,

then if nothing get the injectors tested.

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Wed 25 Jan 2017 09:04
Vauxhall Astra H - astra cdti fuel problem - skidpan

37 mpg from a diesel used mostly in town is probably not that bad. Diesels are not at thier best in stop/start driving, more suited to motorway cruising. Our Mondeo TDCi 130 struggled to beat 35 mpg in those conditions and the C-Max TDCi that followed never beat 40 mpg in town. Once on the open road both would do the mpg figures you would expect.

Try a dcent run and then report back.

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Wed 25 Jan 2017 10:54
Vauxhall Astra H - astra cdti fuel problem - frogmarch

Hi thanks for replies have had it scanned and no fault codes apart from p0380 glowplug error but going to test them soon but looks a pig to get to , as it take a bit to start when cold and also when hot it won't start as it should .

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Wed 25 Jan 2017 12:40
Vauxhall Astra H - astra cdti fuel problem - elekie&a/c doctor

As I suggested in a previous post,there is no need to access the glow plugs directly to test them.

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Wed 25 Jan 2017 19:34
Vauxhall Astra H - astra cdti fuel problem - hardway

Might look "A pig" but book time for swaping all of them is around an hours labour.

Get a garage to quote you.

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Wed 25 Jan 2017 19:41
Vauxhall Astra H - astra cdti fuel problem - elekie&a/c doctor

Agreed,Probably is around an hour on a 16valve engine.8 valve engine looks a lot more involved.

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Wed 25 Jan 2017 21:47
Vauxhall Astra H - astra cdti fuel problem - frogmarch

Hi defence to testing glowplugs someone said you do not have to access glowplugs to test them how do you test them without getting to them,

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Thu 26 Jan 2017 09:40
Vauxhall Astra H - astra cdti fuel problem - hardway

Simple if you have the right tools,

in this case that would be an inductive Ampere clamp and a multimeter and measure the current draw.

But without those tools it's as easy to remove them and connect each across a battery and if working you can see why they're so named.

Bad plugs usually have a damp black tip,

good ones don't as they burn off any residue when hot.

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Thu 26 Jan 2017 10:11
Vauxhall Astra H - astra cdti fuel problem - Peter.N.

The cold weather is having a marked effect on the fuel consumption of both my 406Hdi, presently it is in the mid 40s in the summer its up around 60 mpg.

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Thu 26 Jan 2017 14:51
Vauxhall Astra H - astra cdti fuel problem - hardway

If I were you I'd be checking the thermostat operation and the coolant temperature sensor.

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Sat 28 Jan 2017 18:45
Vauxhall Astra H - astra cdti fuel problem - frogmarch

Hi thanks for replies I have been on a run of about 17 - 20 miles and reset computer and when I got back it read 46.9 mpg ,when I first got car it said over 50 mpg . I am going to have a look in a couple of weeks and look at glowplugs , also when engine is warm it takes a bit to start could coolant temp sensor be a problem.

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Mon 20 Feb 2017 17:43
Vauxhall Astra H - astra cdti fuel problem - frogmarch

Hi with reference to my thread about my fuel problem , I have cleaned egr and throttle body ,they was not that dirty but cleaned them till they shone , runs a bit better but juddering at 1500 revs is still there a bit , there is no codes only po 380 for glowplug error am going to change plugs in near future what else could it be thanks

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