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Model specific boards => Golf mk3 => Topic started by: Sprakie2008 on 25 June 2013, 20:31
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Hey guys, I could really do with someones help! I'm lost!
Basically, some of you may know i have a supercharged golf GTI mk3, 8v... On idle it is hunting like hell! with popping and uneven sound coming from the exhaust. Then under load it coughs and splutters, and just sits at around 4k revs (pinking). I assume this is starvation of fuel seeing as though the spark plugs are showing signs of getting very hot!
Things I have tried to get rid of the issue:
Airflow Meter x3 - including re-wiring and repositioning!
Ignition coil
Dizzy + Rotor arm
Plugs
Gapping the plugs
leads
Fuel pump (3+4 Bar)
Air Temp Sensor
Coolant temp senser
Knock sensor
Timing
New fuel pump
Relays
Lambda
Thats all I can think of right now, no doubt you will have made suggestions I have already tried.. But any suggestion is helpful!!!
Also, I get the Sporadic Short - Upper Stop Value (Lambda) on the Vagcom; but its the hand held one, not the computer software so i cant post a screenshot!
Hope to get some help from you guys! Cheers
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What engine code?
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Engine code is AGG, Sorry should have put that!
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While I was reading this air leak sprung to mind,ie hunting and weak mixture
btw im not a genius lol
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Does it cut out at all?
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I thought air leak at first, but can't seem to find one!
And nope, never cuts out!
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I don't see fuel filter on your list?
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Furl filter has been changed, one of the first places I checked!
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hi have you checked your fuel pressure?
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◆ If the fault "Lambda control upper stop value" is recorded, this means that the lambda control has reached the "mixture enrichment" regulating limit. However, the lambda probe is still detecting a "lean" mixture.
Lambda control
Upper limit value
- Short to earth
- No Lambda control
- Check Lambda control
- Injector defective (blocked)
- Engine running problems
- Check injectors for correct flow
- Fuel pressure regulator defective
- Check fuel pressure regulator
- Fuel pump defective
- Check fuel pump
- Unmetered air after air mass meter
- Check intake air system for leaks (unmetered air)
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Was it running fine?
Sounds like needs mapping to me.
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I'm with Tweed. What's been done to the ECU?
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Was it running fine?
Sounds like needs mapping to me.
Agreed, underfueling is going to be down to the mapping etc.
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Oh and have you got bigger injectors?
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Lol I didn't realise this was a new conversion and has never ran right since build,i agree about remapping :tongue:
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you could try squeezing the fuel hose on the return line to the tank to see if it smoothes the idle out at all as a quick test. best make sure your feed from tank is well secure first though in case it pops off when pressure builds up in line. was the compression dropped and what kind of cam you running?
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ah just thought of something else. is the cat in exhaust blocked???
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It is running a brand new set of
G60 injectors which have been change to another new set! It has also been mapped by Wayne Schofield down at ChipWizards and was putting out 184. It's slowly got worse over time it seems though! The exhaust is not blocked, took the lambda out so there was a nice big hole so obviously could let more out, but still didnt solve the problem. Fuel pressure is it 2.5 on idle and goes up to 3 on revs, tried with my mates g60 pump and it is better, but not perfect so I assume it's just over compensating for another fault?
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Maybe it is time to look at an aftermarket managment set up, it sounds like that even mapped it is struggling to cope.
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try blowing some smoke through the intake ducting just to be sure you got no air leaks before the head. maybe a manifold or throttle body gasket is been pushed out with the charge pressure?
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try blowing some smoke through the intake ducting just to be sure you got no air leaks before the head. maybe a manifold or throttle body gasket is been pushed out with the charge pressure?
surely he got a boost gauge and can see a drop in psi?
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Maybe it is time to look at an aftermarket managment set up, it sounds like that even mapped it is struggling to cope.
I agree
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try blowing some smoke through the intake ducting just to be sure you got no air leaks before the head. maybe a manifold or throttle body gasket is been pushed out with the charge pressure?
surely he got a boost gauge and can see a drop in psi?
[not sure what he has to be honest. just know its a supercharged agg and throwing some ideas out there. anything is worth a try at this stage./quote]