Ok where do i start.

Car is costing a fortune due to MPG giving a good 25% less than usual.

I could get 44+ on the motorway now its 35 if i'm lucky and average was 33 now 25.

I will check the following,but any other suggestions will be welcome.

I do suspect it could be broken pipe.

Plugs

All hoses

Align TB

Have changed MAF for a old spare one i had.

After all of the above i can plug in vagcom but what should i check.

TIA

Check the exhaust for leaks before the cat and give the cat a shake and see if it rattles.

A leaking exhaust or a knackered cat can put the MPG right down (although the performance goes up LOL)

Engine temp sensor might be failing, like mine (green top are better) this will definitely affect MPG

I changed the spark plugs and got a big shot with the ones that came out.As you can see they are not good.These were purchased off ebay about 10 months ago.Swapped then for the old ones had kept.

All of the plugs were the same red colour as if they have been overheating.

I do have the green sensor but may changed it.

Car really struggles to get near 40 mpg and thats driving like a granny.Its min 20% down.

Edited 7 December, 200916 yr by jaymd

What plugs you using Jay? you should be running something like the NGK BKR7E's gapped down for stage 2 mapped. They are a colder plug as well. I had problems with mine blowing coil packs as the Bosch Super 4's where just too big a gap.

What plugs you using Jay? you should be running something like the NGK BKR7E's gapped down for stage 2 mapped. They are a colder plug as well. I had problems with mine blowing coil packs as the Bosch Super 4's where just too big a gap.

Using standard plugs gapped to .8mm and i haven't had any problems with them until now.

I had the same problem with number 2 blowing up slightly until i cut a small 'V' groove in the ribbing of the coil packs.

Does anyone now what reading the front and back 02 sensors should read at idle.

I'm beginning to think it could be the fuel - I know of too many cars including all 3 in my household that experience lower mpg figures and have done over the past few months. Its been mixed whether as well so can't put it down to cold weather.

I may be way of the mark of course but thats my thoughts.

I have noticed that mine has dropped, think it may be down to the changeable weather.

the only thing I have done in the last few days is to change the temp sensor as it developed a fault and that has improved it a little but it could be coinsidence

Yeah mine seems abit lower too recently, seems like it could be the weather then.

Fuel quality is usually good in the UK, in the States they use winter diesel in some states and this can affect MPG but I dont think there is a similar product in the UK.

Jay, i'm getting around the same as you, so maybe wouldn't worry too much about it, and my mods are almost in line with yours.

Jay take your foot off the right hand pedal lol

i only find mine drops bad when i have engadged warp factor 5 lol

Good news is i checked everything and then splashed out on a new temp sensor and it's worked.

I have been driving like a granny getting the fiqures i quoted,keeping under 2k rpm.

At least i can put my foot down a little now.

Wonder if i should do the same Jay ?

Wonder if i should do the same Jay ?

It worth a try.

Mine is running stage 2 but i was getting good mpg figures if i don't floor it all the time.

Good news is i checked everything and then splashed out on a new temp sensor and it's worked.

I have been driving like a granny getting the fiqures i quoted,keeping under 2k rpm.

At least i can put my foot down a little now.

Fingers crossed for you my dear

Hopefully found the answer

Sarah

Wonder if i should do the same Jay ?

I changed yours nearly 3 years ago

Since my stage 2 mine has returned 28-30mpg over a full tank and about 38-40mpg on a run.

Definately no worse than when it was stage 1.

Hopefully it get's sorted mate

I changed yours nearly 3 years ago

I changed mine about 4 years ago,from the original black one.

Since my stage 2 mine has returned 28-30mpg over a full tank and about 38-40mpg on a run.

Definately no worse than when it was stage 1.

Hopefully it get's sorted mate

I will know later when i get to take it out.Washed it as well today.

wheres the cheapest place to get an original green top sensor then? As I really need to get mine sorted soon.

wheres the cheapest place to get an original green top sensor then? As I really need to get mine sorted soon.

I just went to VW as Skoda didn't have any in.£30 + p fr sensor and new o ring.

I just couldn't be arsed waiting for one to come in the post.

Hi, how the.... do you unplug the dam thing, the connector just wont budge. Want to disconnect to try see if it cold starts better as its a bit hard and smokey spluttery when cold. ok rest of time when hot. It was hard to get the connectoer off the sensor on pipe just from the air box. had to get screw driver to prise it off.