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Discussion Starter · #1 ·
Hi all,

Im just on to test your knowledge [;)] I have a 1.8t (AGU) and over the last month or so i have noticed it useing more fuel than usual and the idle is not as smooth as it was, there are not flat spots in the rev range but it just doesnt feel as fast as normal. The car is largly stock though it has a smoothed airbox with pipercross panel filter, a forge diverter valve(which has become very audible recently) and a cat back exhaust.

Any ideas what could be up? MAF? Coilpacks?

cheers

jim[:)]
 

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Like A Bawwsss
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The only real prone pipe to split on a AGU lump is the one under the inlet manifold in the middle which heads towards the PCV valve....but i really dont think that would cause the car to use more fuel.

Quick test you can do is to unplug the maf and see how if drives, but since you say its fine through the revs then the MAF sounds good.

it could be a faulty lambda which is telling the ECU to add fuel to the mixture.

Is it using much more fuel?
 

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Discussion Starter · #5 ·
with regards to the MAF being fine through the rev range, i mean when your gunning it, on part throttle the car is very jerky! A mate who is a mechanic told me that if the MAF is fecked it should still pull ok as all the values when you gun it just go to max but it will show up on part throttle as the values will be all to pot because of the dodgy MAF???

Its using a bit more fuel, i used to get about 200 miles to one section under half a tank and now its just over half a tank[:(]

hope this helps[;)]
 

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Like A Bawwsss
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You mechanic mate is wrong [:D]

What happens, is theres a sensor in the MAF unit which detects how much air is passing by it. This then sends a continous reading to the ECU so it can adjust fuelling and other parameters according to throttle position and the air coming into the turbo.

Without any pointers from a vagcom scan, sounds pretty hard to diagnose as there a quite a few things it could be, so would be stabbing in the dark.

Could be a lambda issue or just down to the weather recently!
 

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You mechanic mate is wrong


What happens, is theres a sensor in the MAF unit which detects how much air is passing by it. This then sends a continous reading to the ECU so it can adjust fuelling and other parameters according to throttle position and the air coming into the turbo.

Without any pointers from a vagcom scan, sounds pretty hard to diagnose as there a quite a few things it could be, so would be stabbing in the dark.

Could be a lambda issue or just down to the weather recently!
go chris go chris!
 
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