mk4 2.0 gti burning too much fuel HELP !!!!

[capone]

just bought a 2000 plate 2.0 litre gti was stinkin of fuel the next day put it on a diagnostic machine and came back with the fault codes
 17536 bank 1 longterm fuel trim system to lean p1128.
 16684 misfire recognized intermittent p0300.
 16687 cylinder 3 misfires detected intermittent p0303.
 16688 cylinder 4 misfires detected intermittent p0304.
the guy in the garage wasn't much help but cleared the fault codes
i've checked the maf sensor looks new so been replaced at some point but i took it off and cleaned it with some ipa spray ! i've put 20 quid of fuel in and barely got 50 miles out of it bit excessive i think ! i don't know where to look next maybe the o2 sensor never had a golf before just wondered if anyone had experienced similar probs and are they common faults with the mk4 ? thanks in advance for replies some help would be much appreciated cheers ! oh yea the car itself seems to be running ok maybe idling a little low. Also the mpg digital gauge fluctuates all over the shop anything from 15 mpg to 110 mpg is this normal ?

[kahunajb]

I vote gobbling fuel. Sorry can't tell you why tho.

As for the mpg its just telling you what mpg the car is doing at that moment which is pretty useless. If you press the button on the right hand stork once it will give you the average mpg for your trip which is much more useful although possibly not 100% accurate.

[Wayne]

2.0's tend to suffer maf problems.

[capone]

i've read they suffer maf probs but when i removed it was clean as a whistle looked like it had been replaced recently was a bosch 1 ! the average mpg for my trip was 20 mpg pretty poor as i was taking it pretty easy !

[Wayne]

i've read they suffer maf probs but when i removed it was clean as a whistle looked like it had been replaced recently was a bosch 1 ! the average mpg for my trip was 20 mpg pretty poor as i was taking it pretty easy !

Might be worth trying a temp sender as a 1st step.