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Discussion Starter · #1 ·
Hi guys, i had a rolling road test done yesterday because i had a funny feeling something was'nt quite right with my 1.8T AGU.

My feelings were right, it put out 144bhp at the fly, and only 122bhp at the wheels! i have a cat back milltek system, big bore TIP, CAI, Forge Diverter valve and a remap. All of these mods should be putting me at the 190 - 205bhp mark but im not even close!

Can anyone shed some light on the possible problem(s) for this absolutley SHIT result?
 

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MAF would be one, temp sender another possibility. have you had a diagnostic check done? I wouldn't get too desheartened it's hard to get power out the agu with the standard ting turbo. first time I had mine roaded in similar spec to you bar tip I only made 188 at fly, basically you need the later engines turbo or something bigger to make a good figure as the standard turbo just can't flow enough air
 

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Discussion Starter · #3 ·
The MAF has recently been changed (about 2months ago) iv Changed every sensor i can think of including the temp sendor, MAF, Lambda probe. i just dont know whats causing this the only thing i can think of is that its not holding/producing much boost at all! could the turbo be on its way out or would it be split hose related? Would that cause such a big drop in BHP?
 

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If youve gone over a service interval dosnt the ECU lower the boost down as a safety mechanism??? Mine halved the boost and had to have the ecu zapped to get it to return to its previous level!!!to say it was sluggish during this week would eb an understatement-1,4 petrols were on par!!!
 

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Discussion Starter · #5 ·
Not really sure about that to be honest. what do u mean by have it zapped again? remap re-done? i know that feeling i had a little tear up with my mate 1.6 and i wasn't going too far without which he was shocked at too!!!

Can anyone else shed some light on this as iv spent a fair few penny's on it and im not gettin even the minimum results!!!
 

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... what do u mean by have it zapped again? remap re-done?...
That wont be required, the software on the ecu can't change itself. Sounds more like you've got a boost leak somewhere. Does the car feel sluggish to come on boost? Make sure you give the hoses a look over and check the divertor valve, even though its a Forge they can still leak.
 

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Discussion Starter · #7 ·
oh yeh defo it feels like it take a small millenium to come on! the guy at the rolling road place said he couldn't feel the boost kick in at all! what pipes should i check and how do i check if the re-circ is leaking boost? it has the standard spring in it does it need the next one up to handle higher boost?
 

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You could try disconnecting the battery for at least 10 mins for the ECU to reset.  But check for boost leaks/split hoses etc first.
 

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As said above check the pipes for a leak. Have alook at the lower intercooler pipe, mine blew off the other day and the car was un-driveable! Also check the pipe running from the top of the dump valve that goes back to the top of the turbo pipe, this has a habit of splitting due to its curved design.
 

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Discussion Starter · #13 ·
Could the lower intercooler pipe cause such a high drop in BHP? This drop in power is a real kick in the nuts cause i love to drive my car and have spent quite alot of time and money on it!
 

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it could be boost leak, get a vag com on there, get the system pressureised, some times leaks cannot be heard. but bad maf, map sensor, cloged filter boost leak are all faults that could caust this, also see if its hitting limp mode?!
 

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"That wont be required, the software on the ecu can't change itself"

It usually has a safe mode-its not a remap it is a standard feature.

Other than that a leaking pipe would seem most likely as most people seem to be suggesting.

Only thing i could possibly sugest is the injectors cloggng or the fuel pump?
 

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Discussion Starter · #19 ·
myk3, how can you tell if your hitting limp mode? i dont ever get any warning lights or anything? what pipes should i check first and how do you tell if they are leaking?
 
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