Author Topic: Help! Boost issue 1.8t  (Read 4311 times)

Offline Jordan_gti

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Help! Boost issue 1.8t
« on: 08 July 2017, 12:39 »
Afternoon, Ive just got back from the company who are going to remap my 1.8T, and they have told me its running low on boost, its currently running at 0.4Bar but apparently it should be at 0.6Bar? I had boost issues in the past that were fixed by a MAP sensor on the intercooler, which gives me the 5-6PSI of boost I get currently, which I thought was normal for a 1.8t AUM engine? But he's given me a list of possible things that could be causing it, exactly as written below;

Possible Reasons:

*N75 Valve (Already changed once)
*Leaking DV valve (I have replaced the standard one with a Forge 008 & just tried switching back to the standard one but no difference)
*MAF Sensor (Replaced with working 2nd hand part about a month ago)
*Turbo Actuator
*Turbo





Please somebody help, they've quoted me £60 an hour for diagnostics & I don't want to pay that if I can help it as the tuning session & rolling road is already costing me £330.


Many many thanks in advance
2002 Golf Gti 1.8T (AUM) LC9Z

Offline Jordan_gti

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Re: Help! Boost issue 1.8t
« Reply #1 on: 09 July 2017, 09:27 »
*BUMP*
2002 Golf Gti 1.8T (AUM) LC9Z

Offline lemski

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Re: Help! Boost issue 1.8t
« Reply #2 on: 09 July 2017, 21:21 »
Have ypu checked for air leaks around all the vac lines. If your stuck and need a pair of hands i can swing by as your only in bristol.

Offline Jordan_gti

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Re: Help! Boost issue 1.8t
« Reply #3 on: 10 July 2017, 11:08 »
The guys said apparently there were no leaks on the smoke test, they did mention how my oil dipstick was broken & they are replacing it free of charge. Really appreciate the offer by the way :) I've just purchased the full version on VCDS, so I'm gunna scan it and test all parts to see if any need replacing
2002 Golf Gti 1.8T (AUM) LC9Z

Offline Jordan_gti

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Re: Help! Boost issue 1.8t
« Reply #4 on: 10 July 2017, 22:04 »
Right so Ive checked all pipes as best I can, no leaks at all, I even removed the rubber section of the standard TIP & checked for leaks & that is good. Ive also cleaned & re-aligned the throttle body, no difference. What is the correct boost level for a 1.8T AUM 150BHP golf ?
2002 Golf Gti 1.8T (AUM) LC9Z

Offline lemski

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Re: Help! Boost issue 1.8t
« Reply #5 on: 11 July 2017, 13:22 »
I dont know. Funnily enough i only worry once there mapped and dont boost as high as expected. But even thats down to the map.

If you unplug the n75 itll put the car into using turbo pressure instead of the n75 to set boost. See if that makes it boost higher or not

Offline Jordan_gti

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Re: Help! Boost issue 1.8t
« Reply #6 on: 19 September 2017, 12:16 »
For anyone who's interested & has the same issue with theirs and has lost all hope... Check your waistegate adjustment, mine was seized & just needed freeing up!
2002 Golf Gti 1.8T (AUM) LC9Z