ERROR CODES HELP PLEASE 1999 GTI, AGU

[swanson07]

hey,

had my car scanned tonight, couple codes came up wondering if people could give me some recommendations

heres the story so far, brought the gti, had an turbo oil leak, replaced it, fine for 1 week, having power loss issues, scanned it and have errors, booked in to get tuned up in a fortnight.

P0121 - Throttle Position sensor (G69)

00575 - Intake manifold pressure - sporadic - resulting limit not reach


those are my two issues, have factory recalculation valve in place. massive front mount, Turbo is a holset HX35 on 18psi, Chipped ecu - unsure on what chip.


Will be very grateful for your help as I live in New Zealand and the mechanics aren't to bright on VW's

[swanson07]

Bump. Need help asap as its my daily driver and worried im doing damage

[GTi_James]

christ NZ?! lol

i  dont know about them codes, the 00575 spunds like the throttle body needs a clean and you need to check all your vac pips though if its sporadic then it could be just a engine "splutter", have you rescanned since?

throttle position sensors a easy fix, could also be a splutter. have you rescanned?

[swanson07]

Cleared the codes the next day. Rescanned same issues. Yea we mod our gti golfs down here too!! Lol

So you reckon clean throttle body and that might clear it. Its not idling proberly seems bit up and down like a rotor

With the other code i read something about checking intake piping for leaks? Maybe they didnt hook it up properly when the replaced my turbo?

Thanks for your post @GTi_James

[GTi_James]

yeh give a clean up, and check all your vac pipes, be a good chance to get a catch can fitted too if your under there and remove the n249 valve

no probs mate

[Wazzzer]

He could remove his N249 if he had one

[GTi_James]

oh yeh hes not got AUM lol my bad

[swanson07]

Turns out I need a tuneable ecu, I have boost leaks, exhaust leaks, and a worn out coil pack

Recomended Tuneable ECU?? cheapest option would be prefer, a G4 link installed is about 4k NZD

[Jin_C]

What?! Who suggested a tuneable ECU?

How do you get from physical hardware issues to an engine management replacement? Could you ask the person who suggested that for their thought process please.

Here are my thoughts if the issues you mentioned are correct

Boost leak - Find them and replace the pipe. Preferably with silicon hose replacement as these tend to last longer.

Exhaust leak - If this is after the lambda probe it wont make a different. If it is before the probe then depending on what the exact issue is you may have to replace the downpipe and catalytic convertor or it may be simply replacing a gasket. If you do not have issues with emissions testing you should go for a decat.

Coil packs - The chances of an AGU engine coil pack failing are very low (note not unheard of). I would check the ignition amplifier module that bolts to the airbox first, these fail much more.

[swanson07]

Hey man

I have the boost leak, one coil pack and exhaust leaks, but to make everything worse I have a engine running lean.


Current Mods on standard internals, Eeeek! be aware lol you will be shocked at my risk so far


Larger intercooler
Holset HX35 Turbo running about 15psi -20psi
SSQV BOV factory piping
Superchiped ECU - REMOVING ITS KILLING MY CAR!
K&N pod filter - the way previous owner installed intercooler ran where airbox was so had to put in POD


So I got it Dyno'd the other week, they tested heaps and found out about my leaks and coil pack also my spark plugs had to much gap and im only getting 129KW at the wheels - nothing compared to when I had my T3/T4 (ended up failing after 6 years)

They recommended fixing spark plugs, leaks, and coil pack, bring it back and they'll install a tunable ecu. issue with that is they want to charge me half the price of the car! and im not confident in installing it myself. Since it is an AGU engine I cant just wire in a new ecu due to the throttle body, so they need to Piggy back on a "G4 link" but I want a cheaper option. Apparently if they install the link then they can remap the fuel to fix my car running lean and tune it to be stable and run alot my KW's, They recon they can get a stable 300HP - 400HP depending on what issue they find.


Thanks

@Jin_C