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General => The garage => Topic started by: azzsmith on 22 February 2013, 16:30
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Hi all, my car is set up for stage 2 and I bought an already mapped ecu from someone and had it coded in today.
All is fine at idle and it is definately quite a bit faster but under harsh acceleration there is a missfire, it goes all judery and sometimes pops and holds back?
Contemplating whether or not to change coil pack but was just wondering if anyone ever had anything similar?
Cheers, aaron.
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So you've bought a pre-mapped "stage 2" ecu? That's your problem right there! A proper stage 2 map should be done on a rolling road so it can be customised to your car/mods.
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What do you mean thats the problem?
The bloke that coded the ecu (works for revo) said that after mapped ecu went in all four spark plugs sooted up so he changed them but apart from that he said that everything else was working really well?
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What do you mean thats the problem?
The bloke that coded the ecu (works for revo) said that after mapped ecu went in all four spark plugs sooted up so he changed them but apart from that he said that everything else was working really well?
I mean that a "Stage 2" map should be unique to your car and your mods, for this to be done correctly it should be done on a RR. In your case this has not happened.
Who mapped the ECU? Was it removed from another car? If so what mods were they running? Are your mods identical?
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The ecu was mapped by jabbsports and removed from another agu golf... All mods are the same apart from fpr. Mine has 3bar and the other car had 4bar. The bloke from revo took some logs and said that the fuel in and out was spot on.
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Also should I change all four or just find the one that is failing if it is the coil pack?
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Missifre on an AGU is normally the ignition amplifier on the back of the airbox
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The ecu was mapped by jabbsports and removed from another agu golf... All mods are the same apart from fpr. Mine has 3bar and the other car had 4bar. The bloke from revo took some logs and said that the fuel in and out was spot on.
Fair enough, probably not the map then!
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Thanks mate, do you know roughly how much from vw for ignition amp and would that cause a miss under load only?
Cheers
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you can't check fuelling properly on an AGU by taking vagcom logs, you need an external wideband. It could be leaning out which i've seen many times and can cause the symptoms you describe, usually down to a weak fuel pump. It could be the ignition amp.. but i'd get the fuel and boost logged properly on a dyno before you go spending money on parts.
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Ok thanks topher, do you think a 4bar fpr would be needed?
The car the ecu came from had one. :huh:
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i dont know if the injectors maxing out with that fpr in will cause a lean enough condition for the backfires.. thats usually more a sign of weak flow from the pump. Or sometimes even lean running from massive overboost will do it. still, if you have free access to a 4 bar fpr its worth trying. even if it feels better i'd get it checked out properly before trusting the map to be fully compatible with your hardware
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Ok mate, weird thing is it only does it on really hash acceleration, if i drive "normally" its fine!
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Sounds like a lean misfire from my experience. had the same issue...under load it misfired, partial load it was fine.
Could also be a coil breaking down, I had that too.
Id be starting with the fuel pump like Topher said. Get rail pressure logged on a dyno and make sure all is fine.
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Thanks chris... should have mentioned that before i put remapped ecu in it was boosting to 0.7bar and now it's 1.3bar, does that sound about right?
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18psi sounds good.
just careful when its misfiring....dont want anything melted.
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MELTED?! :shocked:
Do you think i should try putting in calibra injectors? I have them in the boot lol.
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No, probably make it worse.
If its your pump weak, like i suspect...only thing is a replacement intank pump, or put old ECU back on until you upgrade.
I cant see the FPR making a difference as 4bar gives 15% more fuel in theory.
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Ok thanks chris, I was gonna buy a replacement coil pack tommorrow from vw and try that but should I try fuel pump first or maybe ignition amp?
The only reason I say about the injectors is that baxxy thinks the car it came off had bigger injectors but hes not 100% :huh:
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Doubt its either, ignition amp usually go all the time causing continous misfire.
What injectors were in the car? Could well be a overfuel now you have suggested that. You would NEED to use exact same injectors as what the ECU was mapped on.
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Think baxxy said they were 660 injectors but hes not sure :huh:
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Right, just tried the injectors and on idle was fine for about 3 or 4 mins then went lumpy so dont think it needs bigger injectors.
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Been back to revo today and the car has been diagnosed to have all four coil packs failing :sick:
Getting replacements from gsf tomorrow, hopefully all will be fine after that... fingers crossed.
Thanks for everyones help :smiley:
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If its AGU coil packs...you will be the 2nd guy Ive come across with a failing coil....Myself being one of them. New coils from TPS are £160.
Did they check anything else? or just see the problem and suggest coilpacks? Im still going for Fuelling.
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He said that it was definately an electrical problem because the misfire feels really aggresive and juddery which is what my dad said as well... he had a spare set of coil packs and apparantly the car ran fine with them in... we shall see tomorrow... :undecided: :undecided:
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We shall. As above. I shall be surprised.
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Well hopefully it is, coilpacks aint cheap... wish it just had the one coilpack like my last golf!
He actually said that three of them are failing and the last one isnt great (non genuine).
Fingers crossed :whistle:
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Well, just got back from gsf with new coilpacks in and... touch wood no misfire :whistle:
Car feels really quick, just need better tyres now and bigger brakes lol.