Please help with advise guys.

I have 2001 VRS 1.8T standart version without any modification.

It was running great for first 2 or 3 months. It has 116k on the clock. Also please excuse my ignorance and lack of proper knowledge about cars and all english terms of each parts etc... I am photographer, unfortunately not a car mechanic

For last 2 moths I had almost no acceleration on low rpm. Very flat and dull some times even hard to pull in to main road quickly enough to merge with flowing traffic, but once turbo kicked in around (1800 rpm ) it felt alright.

Recently even once the turbo kicks in it feels like holding back or not getting to the full swing. I would say 40% worst then it was when I bough it. So now I have something like 1.8 diesel without turbo :((

I have done following, none of that helped and I am getting crazy now as it feels like dying under my feet. It is in great condition. One owner since new and all services done in Skoda.

I took it to my local garage they plugged it in and found this code : 17705 P1297 Connection turbocharger to throttle valve pressure dropped : So he changed the valve and related pipes and it did not help - £159 :((

Service done 3 weeks ago. New oil and oil filter, and over all car health check. No fault codes. No advice about what it can be.

They told me that I am due to get new coils so they booked me for next day. Picked up the car and Eureka it was going like a dream again. But only for about 20 miles till I got back home. Next day back to dull mode.

Since then we tried :

Put new spark plugs in - did not help

Took coils of and put them back on - did not help

When we plugged computer in and measured how it goes during the acceleration the curve was flat until the turbo kicked in and then it raised in 90 degrees. I have been told thats not right, it should be steadily rising curve not flat and then peaked in 90 degrees.

So we tried new MAF sensor - did not help

Tried new Dump Valve - did not help

Smoke test done to find any leaks - no leaks found

Air filter checked and its clean.

I took it to local garages. All plugged it in the comps and there were no fault codes.

Even the guy who was doing all tests on it and helped me with maf and dump valve and smoke test said he can't help me any more as he just don't know what it can be. All obvious things we tired and nothing.

Over all it feels like the car is choking, like when you have asthma attack but permanent one, feels really really weak. Please help. Any advice will be appreciated because as I have mentioned my knowledge about cars is limited..

Could be a dodgy N75 valve, but you should read this. http://uk-mkivs.net/forums/p/170257/1115840.aspx#1115840

Also take your throttle body off and clean it all with carb and choke cleaner...They will affect it to,and is a known problem..

Thank for reply guys.

Two more people came back to me with suggestion that it may be problem with turbo or faulty computer. Do you think that based on my description of the problem it can really be turbo or comp ?

Many thanks. I should definitely look in to these two options (n75 valve and cleaning throttle body) first before attempting anything with turbo or computer...

17705 code is purely a gremlin in the software as i've stated many times i had that code written out when my car was mapped you've tried all the obvious things as guy's above have said n75 valve/clean your TB

Also take your throttle body off and clean it all with carb and choke cleaner...They will affect it to,and is a known problem..

+1

Try this first. £2.50 for a gasket & £2.50 for some carb cleaner. 10 min's work. Search on here for instructions.

The throttle on your car is driven by a small electric motor. The throttle body gets gummed up over time & the throttle sticks. Causes rough running & loss of power.