2001 S40 T4 lacking boost - help please....

[madhou5e]

Hello all, I run a 2001 S40 T4 and in the last day or so the car feels noticeably flat.

I have owned the car nearly 6 years and it's never missed a beat. Always runs on V-Power and Tesco 99 juice.

It has always had an aggressive kick when coming on boost and around 2300rpm as it spools up there's always been a little owl like whistle along with the muffled whooosh as it spools followed by the heavy 'sigh' sound as you back off the throttle.

This morning I've paid attention to the cars noises and there's sort of the muted whoosh and a slight 'sigh' sound, the usual owl like whistle however is not there (noticeable as I hold around 2700rpm going up in traffic, a 2nd gear hill each morning to work) but certainly no punch in the back of boost.

I've looked at the hoses (briefly) and all appears ok. The turbo control valve (the little grey box on the side of the airbox) sounds like it has a pea rattling inside it if you rev the engine. Is this normal?

I've also read this morning about the actuator arm being duff. Now I have had a rattling sound as the revs rise for a little bit but put it down to a heat shield vibrating. This 'buzzing' has been with me for ages.

Can someone offer some help please as we're due to drive to the South of France soon and this is something I don't need right now.

I'm missing the hefty punch my T4 has always given

[LiamT4]

Could be a few things. Any warning lights on the dash?

You could remove the heatshield over the turbo and check the actuator, although a warn actuator usually results inconsitant boost rather than no boost.......usually, so still worth a check.

Check all the pipes/hoses and the intercooler. A cracked intercooler can result in low boost.

Some strange things that can cause a lack of boost could be a partially blocked cat, or dirty air filter. Although it would have to be a very dirty filter to really effect boost, but it won't take a minute to check, so you may as well.

Maybe get a boost gauge plugged in to see what (and where) its boosting, although if you need it sorting asap, then maybe taking it to a good garage would be the best bet.

[JUDGENINJA]

Hopefully it is something simple like the R-clip breaking on the turbo actuator. Mine broke on the track and it was like driving a 1.1 Fiesta back to the pit lane.