MK5 Golf GTI
		All Things Mk5 => Mk5 General Area => Topic started by: betts on November 14, 2013, 05:11:46 pm
		
			
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				I currently own a prefacelift mk2 Leon cupra which I've just had to replace the engine due to a piston melting and scoring the bore anyway I've replaced the engine with a cdl engine from a golf r, everything's been fitted and it's running ok but when I come to a stop the revs will rise up to between 2-3k rpm and then slowly fall back to a normal idle, I've also had an engine management light pop on and the car has an intermittent missfire, it will be running fine and the then for a few seconds it will be like the cars running on 3 cylinders and then it's fine again. Any ideas guy because after spending 3k on the car I was expecting for everything to be fine 
			
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				have you checked the pcv?
			
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				have you checked the pcv?
 
 
 +1 for this
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				Which map sensor did you use?
			
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				I just changed the block, I believe all the sensors havnt been changed
			
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				I just changed the block, I believe all the sensors havnt been changed
 
 
 Do some forum searching, I remember something similar with a cdl engine and it was that a different sensor was needed depending on ECU.
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				Sorry to sound dumb but what's the pcv?
			
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				I just changed the block, I believe all the sensors havnt been changed
 
 
 Do some forum searching, I remember something similar with a cdl engine and it was that a different sensor was needed depending on ECU.
 
 Sorry to be a pain but have you got any idea what sensor will need changing?
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				can you get a vag com scan done. where are you in the country?
			
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				Nottingham mate
			
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				I just changed the block, I believe all the sensors havnt been changed
 
 
 Do some forum searching, I remember something similar with a cdl engine and it was that a different sensor was needed depending on ECU.
 
 Sorry to be a pain but have you got any idea what sensor will need changing?
 
 
 From memory I'd guess the map sensor...but I maybe wrong.
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				I just changed the block, I believe all the sensors havnt been changed
 
 
 Do some forum searching, I remember something similar with a cdl engine and it was that a different sensor was needed depending on ECU.
 
 Sorry to be a pain but have you got any idea what sensor will need changing?
 
 
 From memory I'd guess the map sensor...but I maybe wrong.
 
 Yeah it's the map sensor but you only need to change that if upgrading from a car that previously had a K03, the Cupra has a K04 as standard so should have the 3 bar (I think it is) map sensor.
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				The golf had a dsg gearbox if that helps. I thought with the cars revs rising after coming to a stop it may be fuel pump related but I havnt got a clue, I'm at the end of my tether  :sick: 
			
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				Yep, needs logging to determine the fault. There are quite a few faults that could do similar to what you are describing, including the runner flap position fault or throttle body fault to name a few. Unless it is logged and you get a code to work from you could just end up doing needless work. :smiley:
			
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				The PCV is the Positive Crankcase Ventilation valve.. it controls the amount of vacuum present in the crankcase, in other words it's a more sophisticated system than cars which simply feature a breather pipe which links into the air intake pipe.
 
 If your PCV fails, you may experience rough running amongst other symptoms.
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				Id check the PCV first. Easy way of checking just search the forum plenty of threads. Second id check for a air vacume leak somewhere. Maybe get a smoke test done.
			
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				I have the latest revision Pcv for sale http://www.mk5golfgti.co.uk/forum/index.php/topic,73929.0.html
			
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				Thanks for all the replies guys, I'm determined to get to the bottom of this problem