My engine management is on, it's been on since I brought the car but was assured by the 64 year old it was to do with unplugging the air mass metre.

When I took it in for diagnostic it came up with 4 things, one was a low maf sensor reading another was something to do with the turbo (the turbo seems to wind up in stages) not sure if that normal, 3rd was the engine temp and I can't remember the 4th.

I got a new coolant temp sensor for it and it's not solved the temp it's still at 70 degrees or lower so got new stat to fit now, I got another air mass but it was off a mk4 gti so the electrical connection is different :( and that's as far as I've got.

Would putting a pipercross increase the air flow and hopefully fix the low reading ?

What likely problem would happen if the turbo came up on diagnostic? It winds up okay does seem a bit like it goes in levels the car seemed allot faster than it does now?

Also the idol isn't always level it's a little lumpy at times, when up in the revs it's fine but let throttle go and it's stalled on one occasion.

It's got a forge dump valve fitted and I'm thinking it might be that causing most of my issues?

Sorry the post us all over the place I hope readers will understand it all.

Thanks in advance.

Dan

Temp problem will be the stat stuck open.

Fitting a new air filter will make no difference to the temp. Fitting a new MAF (genuine) would be better use of your money.

Turbo winding up in stages isn't normal.

You need to get the fault codes & post them up.

Poor idle can be caused by a number of things, split vacuum pipes, dirty throttle body, faulty coolant temp sensor are the usual suspects.

I done the coolant temp sensor already and have the thermostat to fit, luckily in my other post about this I got an answer to where the stat is just need a day off so I can fit it.

The air filter I was asking for the low air mass reading as there was originally an aftermarket fitted, I do have a genuine Bosch air mass here but it's the wrong connectors need to try trade with someone or sell this for the amount needed to get the right one as I can't afford to buy another one!

I haven't had chance to check the throttle body yet, I looked quickly one day and it seems awkward to get to compared to a mk4 golf so it's finding the time to try the simple things like this first before I spend on unnecessary hoses and pipes etc.

I will get the codes up again as soon as I get time to get it in the garage and post them up.

Thanks for your help pauldazzle

The low air mass reading will be because you have the MAF unplugged. If you have an aftermarket cone filter fitted that's sucking in hot air from the engine bay you will be losing bhp.

To clean the throttle body you need to remove it. It gets gunked up on the inlet manifold side. It's exactly the same as a mkiv Golf 1.8T drive by wire. Look on here for how to guides.

Split pipes under & around the inlet manifold are extremely common, have a listen for hissing. You can get vacuum piping from a motor factor for just a few quid.

MAF sensor must be for vrs auq engine, if it`s not it can cause all kinds of problems, especially low readings. There are at least 5 different MAF sensors for 1.8T.

Buy a Bosch one because it`s cheaper then a OEM one, only difference from OEM is there`s no škoda/audi part number stamped on the sensor. 

I do have a Bosch one but it isn't from another Vrs like mine the original is still fitted and is low reading, the engine management was on when I got the car because of the guy putting a cone filter on it but he then got a K&N panel filter and connected it up.

I had the light turned off and codes deleted it came back on 4 days later but then after I done the coolant temp sensor it went off on its own 2 weeks later for a week but is on again now.

Found a split hose off the original air box in amoungst the many pipes to the mid front right of the engine which is tapped up, I'll get a replacement pipe and try that too.

I'll adjust the dump valve to be sure it's not leaking pressure as well as you sometimes hear a hissing (not the turbo)

I'll keep updated with this thread for other users in the same boat.

Thanks you guys.