[chrisp]

I drive a polo 1.4 tdi (2002) and sometimes when i accelerate relatively hard the car almost jerks, feels almost like a loss of power. It shudders at times too. Any help with this would be much appreciated.

 

[Vent5]

Sensor problem. Some sensor is off or bad and it's upsetting the ECM. Check for boost leaks, broken or loose piping, and check the MAF sensor. I don't know if the MAF was also bad on that model but it's a common failure and it'll cause drivability problems.

 

[chittychittybangbang]

It's either a boost leak or limp mode or both.

When you go to accelerate, air pressure from the turbo is leaking out and causing bucking or a sensor is not reading correctly and is causing the issue.

See these writeups:

http://www.myturbodiesel.com/1000q_how_to/multi/boostleaks.htm

http://www.myturbodiesel.com/1000q_how_to/multi/limpmodetdi.htm

Not sure what engine you have but if you have the AGR, ALH, or ASV 1.9L TDI engine, the part number for the MAF on the polo may be 028 906 461. If you don't have that engine, check around for the correct part number.

 

[darren]

Maybe the fuel filter is clogged and is starving the engine of fuel? That could produce the bucking.

 

[cheekymunky]

Could need an adjustment of the fuel pump, the hammer mod. This seems to be able to adjust many people's fueling issues.