Cupra only boosting to 5psi...

[steve0]

I have just been down to visit relatives for the day, and on the way back, just after a good bit of spirited driving on the motorway, it started only boosting to 5psi and will not rise any further. No lights on the dash for miles and miles of it doing it, then when very near home the Engine Management light came on.

It has done this once before - quite a while ago, so I had it VAGCOM'ed, which brought up; INTERMITTENT MISFIRE ON CYLINDER 3 and KNOCK SENSOR FAULT. The mechanic cleared the codes and it hasn't done it since; but has again today. It only seems to hapen on the motorway after using various amounts of boost.

I will obviously get it VAGCOM'ed again asap, until then, any ideas anyone?

Cheers

 

[David_smith_909]

check coilpack/sparkplugs for missfire

 

[__B3NNY__]

Limp mode baby yeh!

Like Dave said check your coils/sparks.

 

[steve0]

Right-0, plugs are near enough brand new - NGK BKR7E with standard gap on a remapped cupra, sound about right?

Il check the coilpacks, is there an obvious way of telling if they're fu*ked or not??

Cheers

 

[David_smith_909]

remove the coilpack from cylinder 3 (looking at front of engine, 2nd one in from right) and swap it with another of your coilpacks

if the fault comes back on the cylinder you just swapped it to you know its your coil, if the problem is still on cylinder 3 it will be the spark plug

 

[steve0]

Right, good little idea that, il give it a go.

Could the knock sensor fault have anything to do with it? Where about's on the Cupra's engine is the knock sensor??

Cheers