Renault Laguna II - using lot of diesel

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Mon 29 Nov 2010 21:55
Renault Laguna II - using lot of diesel - frogmarch

hi my renault laguna dci on 51 plate is using a lot of diesel , in last few weeks its had new glowplugs and relay turbo pressure sensor , intercooler , and had egr valve cleaned by renault dealer who dignosed it. iam putting £10 of diesel in and getting about 55 miles and computer is saying about 33 miles on a run , i hope you can help thanks.

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Mon 29 Nov 2010 22:04
Renault Laguna II - using lot of diesel - Collos25

There is a bit more to do than just cleaning the EGR I am not saying this is your problem but gunge goes everywhere including the turbo viens ,the inlet manifold.and sometimes contaminates the injectors.

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Tue 30 Nov 2010 10:25
Renault Laguna II - using lot of diesel - Fernando P

You will use more diesel in cold weather and when doing short runs as it takes this diesel engine some 10 miles to properly warm up. Try using a main brand diesel as well. If the temp gauge is reading lower than it should, the thermostat may be be faulty, which would make a difference. The MPG you quote is not unreasonable when doing short runs in cold weather. All this assumes that the EGR valve is properly clean and working as it should. If you get a lot of black smoke when you pull away from a roundabout, for example, this indicates an EGR problem.

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Thu 2 Dec 2010 19:54
Renault Laguna II - using lot of diesel - frogmarch

this has happened even in warmish weather . the temp gauge is reading normal , there is a little black smoke on acceleration , do you think it could be egr and air flow meter or injectors , should i put some injector cleaner through it thanks

Edited by frogmarch on 02/12/2010 at 19:57

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Fri 3 Dec 2010 13:09
Renault Laguna II - using lot of diesel - Gregory II

I would say that using injector cleaner won't make a huge difference. Have you checked the really obvious: leaks, tyre pressures. Is power ok? Obviously garages or home mechanics just change anything, when there is an art to diagnostics called 'common sense!!"

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Fri 3 Dec 2010 22:23
Renault Laguna II - using lot of diesel - frogmarch

yeah there is no leaks and tyre pressures are ok , i had diagnostics done at renaulyt dealer for glow plug liht on and loss of power and thy came p with glow plug relay turbo pressure sensor egr valve which thy cleaned , but i am still using diesel , i was getting better mileage out of my petrol vectra , just need help

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Sat 4 Dec 2010 15:02
Renault Laguna II - using lot of diesel - Collos25

Have you cleaned out the inlet manifold and had the turbo vanes cleaned as I suggested and also have the turbo checked for operation ,having worked on plenty of these renault engines untll itsclear of crud then you may as well shove ßßßß uphill.Another problemis the MAF run the car without it connected if its just the same then its faulty.

Edited by Andy Bairsto on 04/12/2010 at 15:05

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Wed 8 Dec 2010 21:09
Renault Laguna II - using lot of diesel - frogmarch

hi no i have not cleaned manifold or turbo vanes , the other thing you mentioned is the maf sensor is disconnecting it and try it , surely if it was this it would put engine light on and is it ok to run it to try and work out how much fuel it is using thanks for your reply

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Thu 9 Dec 2010 15:01
Renault Laguna II - using lot of diesel - frogmarch

hi me again , i disconnected the maf sensor and it was no power on pull away ,so connected back together and power was back . i did put some injector cleaner in the other day and have noticed there isnt so much smoke , but it is still using diesel , thanks

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Sun 26 Dec 2010 12:43
Renault Laguna II - using lot of diesel - frogmarch

hi i just thort of original problem i had . there is power going to relay for glowplugs all the time evan with ignition off and card out of car , would the glowplugs being on all the time cause it to use a lot of diesel.

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Sun 26 Dec 2010 13:11
Renault Laguna II - using lot of diesel - Collos25

No,if I remember there is a supply tothe glow plugs all the time the ignition is on if there was current going to the glowplugs all the time with the card out the battery would be flat in no time.I think there is a supply to the glow plugs for a short time while the ECU shuts down.

Edited by Andy Bairsto on 26/12/2010 at 13:12

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Sun 26 Dec 2010 18:08
Renault Laguna II - using lot of diesel - frogmarch

hi i checked multiplug to relay and there is power to it , i have used car thn left it over nite and still power there . i know it is different but i also get slight hesitation when accellerating in second gear . need to get fuel problemm sorted though thanks

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Sat 8 Jan 2011 20:14
Renault Laguna II - using lot of diesel - frogmarch

hi does any body know how to test egr valve and also how easy is it to take inlet manifold of to clean thanks

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Sat 8 Jan 2011 21:22
Renault Laguna II - using lot of diesel - Fernando P

Given that you do not know the answer to either of the above questions, you need to get help from someone who does. Testing the EGR valve is a job for either the Renault Dealer or skilled Renault "specialist" as is removing the inlet manifold etc. Cleaning the EGR valve and the "throttle chamber" behind it, which does not involve removing the inlet manifold, may solve the problem/improve things for a start.

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Sun 16 Jan 2011 14:12
Renault Laguna II - using lot of diesel - frogmarch

hi fernando p , i do all my own repairs and i have just been out for a drive and glowplug light came on and lost all power , switched engine of then restarted and was ok , got home and put code reader on and came back with df 199 boost pressure sensor coherance btween boost pressure and atmospheric pressure , also airflow meter code , cancelled codes and went for drive and put code reader back on and it came up with boost pressure sensor coherance btween boost pressure and atmosheric pressure , i will have to check wiring , any help thanks

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Thu 10 Feb 2011 21:20
Renault Laguna II - using lot of diesel - frogmarch

hi me again still got probs with laguna using alot of diesel , had diagnostic done at renault garage and was no codes , i sprayed some cleanere in airflow meter and cleaned egr valve again and fuel trip computer went up to 37 mpg still not brilliant . was wondering if i cleaned manifold also got whistling when accelerating but no smoke and also sounds like exhaust is leaking but isnt would it b a inlet manifold problem thanks

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Sat 26 Feb 2011 18:43
Renault Laguna II - using lot of diesel - windywalney

I dont want to point out the obvious but are your tyre pressures right and are all your brakes free from binding...

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