i have a friend with a skoda octavia 1.9tdi 52 reg

now the car is just a basic model but very very slow

i beleiev he had the car on a diagnostics reader and these are the faults

p1156 short to ground presure sensor

p1556 turbo pres control

mass air flow readings low

can anyone please explain what these things are and where i can locate then on the engine

thanks!

MAF is just after the airbox and has a clip plug in it, not sure about the others. Do a search for MAF on here there are pictures and details of how to either clean or replace.

the maf has been changed now

the car is still down on power its as if the turbo isnt runing any boost at all

anyone with any ideas on what the sensors do or where they are on the car?

the car is strugling to cruise at 70 on the motorway!

The turbo, or the turbo actuator, is sticking! ( if its a 110 HP)

Try a search on turbo problems and you will find some nice pic`s about how to fix this!

the 110 only madeit into the elegance and L&K models not the classic and ambiente.

Try here

17964/P1556/005462 - Ross-Tech Wiki

and here

OBD-II Codes

There is a pressure sensor on top of the intercooler, remove drivers headlamp for access, the n75 valve is on the passenger side bulkhead, and there is a sensor on the inlet manifold, which may also be a pressure sensor. The VNT mechanism could be sticking, have come across this on an Ambiente 90hp before.