1.4 HDi Smoke and Dirty Injectors

[Eversor]

Hi all,

I been having a problem with my 206 1.4 HDi where I keep getting one dirty injectors and hence lots of black smoke while accelerating or pushing hard.

So far I have been able to notice some things:

- After injector cleaning, it runs ok for a week on the city, short trips, (one overfuels, another underfuels)
- Starts smelling with unburned diesel even while idling (no smoke)
- It smokes while neutral and accel to 3000+, then clears up if RPM is constant,
- On a 30km journey it cleans up towards the end and smokes a lot less on the previous test,
- There is a clacking noise from the valve cover, louder on acceleration.

Since I'm not a mechanic and local ones seem to have trouble finding the issue, I wanted to ask for some input from experts. My thoughts from this behavior are:

- EGR is not working well and introduces too much exhaust on city miles,
- Glow plugs can be bad and combustion has issues while engine is colder,
- PCV valve lets too much oil through (intake sure has lots of it),
- MAF readings seem ok, as verified by electrician.

Last time the car was on local Peugeot dealer which recommended changing the catalytic converter, which was somewhat damaged but on inspection looked ok except for some damage in the center.
I refused this as I had my doubts this was the cause given it does not constantly smoke. I am now less conviced after it cleared up mostly on a 30km trip.

Any help is much appreciated. Thank you.

[MattBLancs]

Catalyst collapsing= blocked exhaust and lack of power, reluctant to rev or make power which you've not reported, so think can rule that out.

How are you detecting dirty injector?
how are you cleaning?
What mileage covered?
Fuel filter replaced given dirty injectors? If not done suggest cut open the old one (presume is sealed plastic box type like the 1.6 HDi) and see if anything inside.

Glow plugs, starting and initial running only, so should see no difference city versus a longer run.

Would not expect PCV system to affect running. Oily intake fairly normal - yet to see a car with a completely efficient oil separator on the PCV, so inlets always oily.

Long runs generally of benefit to engines, can you take it a much longer run (an hour's cruise at motorway speeds, if wanting to maximize the potential effect perhaps try said cruise in fourth rather than fifth gear) as 30km (about 19 miles) still a fairly short trip

Clacking valve cover noise: very odd, not sure what to make of that at present!

Matt

[Eversor]

Catalyst collapsing= blocked exhaust and lack of power, reluctant to rev or make power which you've not reported, so think can rule that out.

I don't know if that is the case but assumed such amounts of unburnt fuel would lead to damaged cat even if everything flows through. I don't find lack of power if everything is running clean but notice it in precisely the spots where it is blowing out smoke (hard accel and/or up a road). It revs well, though I've had issues for so long that I probably don't know what is normal for this engine anymore.
I have noticed there is a lot of hesitation at low RPMs. Instead of sputtering as in lack of throttle, I am accelerating and I feel some rumbling up to 1750RPM or so, that initially felt like the clucth not hanging on. But if I throttle it to 2000+ and release the clucth it goes fine, no hesitation and some wheel spin - like when I had it new.

When cleared up, I averaged down from 6l/100km to low 5s, which is the normal for this car/engine.

How are you detecting dirty injector?

OBD readings and since the last time, by disassembly. Two were out for cleaning.

how are you cleaning?

Professionally done 3 times over two years. Last one was charged for expert cleaning at a dedicated shop.
When I sway

What mileage covered?

To get them dirty? From professionally clean, less than 200km city driving does it in.

Fuel filter replaced given dirty injectors? If not done suggest cut open the old one (presume is sealed plastic box type like the 1.6 HDi) and see if anything inside.

It's due for maintenance now and will try it. But filter was changed last year and is an expensive one. I will have to check with the OBD but I always got 1 injector diagnosed on two different shops, so I think it should affect all if it is a diesel issue?

Glow plugs, starting and initial running only, so should see no difference city versus a longer run.

But that was what I was thinking, if it runs for a while, I may stop the car on short trips (usually 7-10mins) and the engine will be running dirty almost the whole time? I also read they are used to improve combustion but can't find specific information on this engine.

Would not expect PCV system to affect running. Oily intake fairly normal - yet to see a car with a completely efficient oil separator on the PCV, so inlets always oily.

Ok, thanks. Yeah, I think I should maybe see more oil consumption if this is an issue.

Long runs generally of benefit to engines, can you take it a much longer run (an hour's cruise at motorway speeds, if wanting to maximize the potential effect perhaps try said cruise in fourth rather than fifth gear) as 30km (about 19 miles) still a fairly short trip

I was actually going veryowards t slowly the first part of the trip, as it was putting a lot of smoke. The end it cleared up and even up a "hill" it remained smoke free back home. I have started using a Redex additive, as I had no improvements with additives at the pump.

Clacking valve cover noise: very odd, not sure what to make of that at present!

I will take the valve cover off and have a look. When engine is on and I open the fuel cap it is very noticeable. I had noticed this new noise many years back but could never trace the origin.
Could a problem with a valve cause this and what should I look for as a bad sign?

Best regards

[MattBLancs]

It's due for maintenance now and will try it. But filter was changed last year and is an expensive one. I will have to check with the OBD but I always got 1 injector diagnosed on two different shops, so I think it should affect all if it is a diesel issue?

Clacking valve cover noise: very odd, not sure what to make of that at present!

I will take the valve cover off and have a look. When engine is on and I open the fuel cap it is very noticeable. I had noticed this new noise many years back but could never trace the origin.
Could a problem with a valve cause this and what should I look for as a bad sign?

Best regards

Thanks for all the answers,

Fuel filter pretty recent and decent quality, ok unlikely to be an issue there (unless manufacturing fault= very very unlikely) agree would likely affect all injectors not just one.

Valve noise remaining a mystery. If anything mechanically wrong then would expect permanent fault, rather than the variable symptoms you are seeing.

I don't think the 1.4 HDi has a dual mass flywheel, otherwise would suggest that as potential source of the vibrations.

Mileage - sorry I meant what distance has the car done in total?

However, clogging injectors in 200km doesn't sound good at all, something there to dig into.

If one injector is showing a fault repeatedly after professional cleaning then I'd be tempted to try a (second hand as they aren't cheap) injector in this position. I think are coded so would need Diagbox to do this I believe.


Hmmm, still a puzzler!

Matt

[Huskyxantia]

Piston rings wearing , it will be gearbox end 2 pistons.

[Eversor]

Piston rings wearing , it will be gearbox end 2 pistons.

Hey guys,

Been able to further inspection and don't think it's a piston issue. There is no smoke from oil level plug but there are buffs from the oil filler cap, which is strange. Since I hear some clacking noise, maybe a valve or stem needs replacing? The mechanic removed the valve cover and says all is ok but he seems to miss some stuff.
I removed the air filter housing and had fresh oil around the intake manifold seals. I think this is the cause of smoke at high revs/load, as I usually hear a good increase in engine noise before smoke follows.

As for the gearbox I think it might be the case. What I noticed now is that if I turn the car on in neutral, foot off the clutch, I always hear a screeching sound for a second then stops. This never happens with the clutch pressed. I also hear the same sound in first or 2nd gear when using the clutch to park the car.
I found some grinding on the flywheel teeth and am looking into the starter engine rubbing into the flywheel. But I find it strange that it would only happen in gear. Is the crankshaft subject to some play when the clutch engages? The starter rotor has some play of 1mm or so but otherwise seems to park ok.

This noise only happened while starting the car but, after a year, started happening in the lower gears while moving. Same issues as before, with car being very rough when pressing or releasing the gas pedal - bad at 1.5-2k rev vs smooth on 3k.