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[portomega]

The last 2 weeks i've been getting really crap mpg from the car, normally it will sit around the 26-28mpg but at the moment i cant get it higher than 24 and it will normally stay at around 22-23 , theres no change in my driving or where im driving to, its mostly motorways to and from work. Anyone got any suggestions as to what can cause the mpg to drop like this :-?

[mathewst]

Well there are number of reasons for higher consumption.
Spark plugs
Blocked filters
Blocked breathers
Lambda sensors
Thermostat
Egr and so on.
Check the obvious things first (spark plugs, filters etc)

[portomega]

cheers, will get those checked, only problem i have with the car, engine wise, that i can see is i have an oil leak which is from the camshaft oil seal, had it changed once which cost £200+  but within a month its started leaking again and i cant afford to get it sorted again, would that affect MPG at all?

[mathewst]

I don't think it should matter.
When was the last time sparkplugs were changed?

[portomega]

it last had a full service in May and its done about 5000 miles since then

[mathewst]

Hmm so sparkplugs should be ok.
No spanner on the instrument pannel?
Probably the car could be running rich.
One possibility is to get the codes read.
You could try the pedal trick ( works rarely on 2.2 engines).
Also check the breathers which is pretty easy

[portomega]

No EML , i havent checked the breathers in a while, shall have a look when i get to work tonight 

[Robin Hood]

My MPG has been down the passed week etc and I've traced it to the handbrake (corroded cables).   

[portomega]

lol being an Auto i dont think ive ever used the handbrake in the 2 years ive had it 

[JamesV6CDX]

The reason the seal failed again will be 'cos they fitted a pattern part - they're crap.

As soon as the weather warms up a touch (!) and I'm less busy in the new year, I'd happily give you a hand to pop some proper seals in there....

£200 is criminal, it's only a 2hr job for an experienced mechanic.

[Bionic]

Lets not forget that the ambient weather also plays a part. It affects mine too by about the same amount. GudLuk

[portomega]

They said it would cost £200+ because to do the seal they had to remove and replace my timing belt too, although it was only 3 months old, but they said they felt it should be changed again if it was being removed :-? cold weather can cause the mpg to fall? never knew that :-?

[Andy H]

cold weather can cause the mpg to fall? never knew that :-?

MPG is much worse during warm up than during normal driving so if you do short journeys you will see a big hit. If most of your journeys are an hour or more you probably won't notice a difference.

I wonder if blocked breathers are the cause of your cam seals failing and poor fuel consumption?

[portomega]

i normally drive for around 15-20 mins, on the motorway for about 15 miles ( thats to work mostly every other day) my mpg doing that would normally be around 27mpg , but like i say last 2 weeks, its dropped by 3-4mpg .... i havent had the chance to check the breathers yet due to the weather, they were cleaned about 6-7 months ago when my head gasket was done, would they get blocked again since then?

[sexydaz]

i could do wi checking mine i only get average 19/20 but mainly do short journeys,maybe this could be reason for having to keep topping oil up if blocked breathers have done the seals in