F9Q Gradual loss of power and smoking

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Dirty Diesel
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Joined: 14 Apr 2019, 19:20

F9Q Gradual loss of power and smoking

Post by Dirty Diesel » 14 Apr 2019, 19:30

Good evening.

I am posting this here, as someone who is familiar with the F9Q engines is likely to be here. I own a 2004 Volvo V40 1.9D with an F9Q engine, but I've got a problem.

The matter at hand, is this: my V40 has slowly been losing power, not gutless, but noticeable, and is smoking what seems to be black smoke, with possibly a hint of blue from what I can tell.

Over the course of my ownership, I have replaced/repaired the following:

Cleaned EGR valve

Replaced MAF sensor

Replaced N75 Valve (Vacuum Control Solenoid)

Replaced Turbocharger

I've checked over the vacuum system, and all seems to be in order. Along with losing power, it doesn't seem to idle right either, it jumps around, usually dropping by up to 50RPM, it doesn't sound much, but I know somethings wrong, as it always idles spot on.

I've spoken with the user on the Volvo forum (on which this is also posted) about the matter, and all we could come up with was the injectors. Two of the injectors do seem to "click" more than the other two, when holding a screwdriver to either the top, or the metal base of, the injector, then listening to them through the screwdriver.

I must also mention that I do not have ready access to a diagnostic machine, but have used one recently, and no engine related codes were available, indicating nothing completely gone yet, or any electrical problems. Engine Management Light is also NOT present.

Could anyone shed any light on the matter? It's getting rather annoying, and I'm starting the wonder whether it'll pass it's MOT tomorrow.

Any help is greatly appreciated! Thanks I'm advance

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Re: F9Q Gradual loss of power and smoking

Post by Peter.N. » 15 Apr 2019, 12:00

I'm afraid I have no experience with this engine but I have had similar faults with the Hdi 12 valve 2.0. engine which was due to a faulty pressure regulator on the back of the HP pump, they contain an almost impossible to clean filter but I replaced one with a second hand one from ebay for very little money and it cured the problems.

What I had was 'hunting' on tickover and lack of power at high revs, no smoke that I recall though. The problem could be injectors although I have never had a problem with mine but these are early common rail engines which seem to be somewhat simpler.

A diesel injection specialist would probably be the best person to go to as they usually know what they are doing.