S40: Intermitant Stutter/lose of power

[Stylus]

A friend of mine has a v40 t4 on an r plate and it has the above problem.
It happens when pulling away now and then, once it has done it he says it drives fine. No warning light have come on. Could this be a fuel pump problem.

[MidnightT4]

this problem got me for months. Turned out to be a faulty connection on one of the coil packs. Mine would drive fine at slow speeds but under full load would stutter

[Baffler]

I have started to experience this stutter but only under load. If I relax my foot off the accelerator it will perform as normal. I have asked around and it can be a number of things. For example - this is on the advice of another forum user...

1. Faulty MAF (try not to test with generic SIEMENS ones as they sometimes cause more problems than they cure! Use a genuine Volvo one)
2. Plugs - use only genuine Volvo ones!
3. Fuel pump or pressure regulator - (check fuel pressure with the ignition on for the latter - should be 3bar)
4. Boost control valve hoses - replace all three hoses with 5mm ID braided fuel hose - this is a good thing to do regardless IMO because the standard hoses get hard and split sometimes.
5. Coils - you need to eliminate them one by one unfortunately

Maybe your friend can have the ECU read for faults?

Good advice from MidnightT4.....I must double check that!

[modman]

Originally Posted by Stylus

A friend of mine has a v40 t4 on an r plate and it has the above problem.
It happens when pulling away now and then, once it has done it he says it drives fine. No warning light have come on. Could this be a fuel pump problem.

strangely mine did this yesterday it ran fine for 60 mile trip i got within 5 mins of my house and when i tried to excelerate it started to judder, went out to it this morn and alls well again.

[Stylus]

Cheers for all the help, should see him tonight so will pass on the good news lol.