1.8T MK4 Issues (Codes Included)

[edd]

Hi, I'm new to the forum.

I bought a Mk4 Golf GTI a couple of months ago as I needed a cheap runner and so far have been really impressed. I really don't think I could have got any thing better for the money.

However there are a couple of issues with it. Sometimes when it's cold the idle is rough, there will be a lack of power and can cut out. I've had it in to VW to have the coil packs replaced under the ignition recall, but that doesn't seem to have solved the problem.

The fault codes I'm getting are 17705,17704,16955 (I must have a brake light out), 17545 and 16514.

17705 - Pressure drop between Turbo and throttle valve. But I can't see any split hoses.
17704 - Temp sensor/Thermostat.
16514 - Lambda Sensor.
17545 - Lambda or Maf?

So I was just wondering if any of these codes are common and are there any "cheap fixes"? Or is it a case of getting a new Thermostat, Temp Sensor and Lambda fitted for a start?

Thanks.

[Nino]

I had thous codes, but I haven managed to fix most of them by doing the following:

• Took off my TB and cleaned it up using Carb cleaner (This fixed my lumpy idel).
• Took off the MAF and cleaned it using eletronic cleaning spray (same time as I clean the TB).
• Changed my Temp sensor for Gen OEM from VW cost around £8ish took 5 mins.
• Changed my Thermo for Gen OEM (Never fit a cheap one, and is a pain to fit).
• Put new Forge 007p DV on.
• Checked all the pipes for leak and couldn't see anything....

I then cleared my codes and waited a good month and now the only code I have is....
17705 - Pressure drop between Turbo and throttle valve.

This code is very common, I have just order a whole set of silicone pipes and Im going to replace them all, if this does not fix my problem, its going into a specialist.

[navmk4gti]

May be pipe you cant see from looking over the engine...On my AGU after searching for weeks found intercooler pipe behind bumper part had big slit in it 

[Chris.]

17705 code is a bug in the software.  Pointless chucking money at it and get no further forward.

[edd]

Cheers for the responses, very helpful.

Are there any guides for fitting a new Temp sensor and Thermostat?

[Nino]

Ermmm,

Temp sensor replacement..
http://www.anthonydanna.com/vw/tempsender.htm

Fitting new Thermo...
http://www.golfgtiforum.co.uk/index.php?topic=101783.0

[edd]

Thanks Nino!