Black smoke.

[sammdjo]

Hello french forum.
I'm a new user here for first time.

I have a Citroën C5 X7 2011 2.0 HDI 103kw
Having black smoke issue on acceleration and little diesel knock at idle.

◇ No check engine light active.
• New fuel pressure regulator valve
• Tested all injectors. Two were bad and rebuilt, two other passed bench test OK.
• New crankshaft sensor
• Intake manifold taken out and cleaned.
• MAP & IAT sensors taken out and cleaned with spray.

Any recommendations what else to look for?

[Hell Razor5543]

Have you checked the air filter?

[sammdjo]

Yes. Air filter is clean, and brand new.

[Alejandroxc70]

Since the fuel side has had a lot of attention already, it might be worth looking at the air side next. Black smoke under load usually means more fuel than air, and the usual suspects there are the EGR valve sticking partly open, or a boost leak, like a split intercooler hose or a loose clamp. A leak often shows up as a hiss under load or an oily patch around a joint.

If you've got something that reads live data, comparing requested and actual boost while accelerating, plus the air flow reading if it has a MAF, would narrow it down quickly. A sticky turbo actuator would show up in the same numbers.