No Black Smoke

MikeT · Post by **MikeT** » 02 Jul 2007, 17:34

I turned the smoke compensator torx screw a total 2 turns clockwise today and can't say I notice any difference during the following 5 miles of mostly urban driving.

I'll leave it for a while then set it back to original setting and see if I notice anything lacking then.

The black plastic cover seems to be held on by side clips/lips so should be easy to remove when I'm ready to make changes.

JohnCKL · Post by **JohnCKL** » 03 Jul 2007, 17:18

I think the most gains would be to open up the smoke compensator itself and adjust the diaphragm plunger and toothed wheel. The smoke compensator screw will not make as much difference as the diaphragm plunger which I think is the same function. So far my 30 degree clockwise turn of the plunger and half turn clockwise of the toothed wheel gives good power and little smoke if I don't put my foot down all of a sudden. If you do open it, remember to mark the position of the diaphragm and toothed wheel.

MikeT · Post by **MikeT** » 03 Jul 2007, 19:59

Hi John,

I admit, I haven't studied how these parts work or what they should be affecting exactly but I will tackle those parts you recommend shortly and due to my ignorance will certainly make a record of changes. I'm also mindful that some people reported having to undo certain changes once the best full power setting is accomplished as well as resetting the idle.

MikeT · Post by **MikeT** » 13 Jul 2007, 16:55

After a few weeks of running with the "smoke adjuster" turned C/W 2 turns and eventually seeing a haze of smoke from my exhaust

I decided to set it back to how it was to see if I can notice any differences.

There is no discernable difference worthy of pursuing further so I'll leave it as I found it for now.

Looking for smoke seems a hit and miss affair depending on backlight etc. Sometimes I think I can detect a haze, sometimes a definate cloud amongst a haze, other times I see nothing but clear air. Is there another way to determine the fuelling? I'm so used to petrol engines that I go blank when trying to understand what it means to have too much or too little fuel supplied

I'm now running 100% veg oil if that makes any difference to the fuel metering - it doesn't seem to change the performance except the idle now mildly "hunts" (if that's the correct term?).

Cold starts are interesting too with lots of white smoke and the need to add a touch of throttle for 30secs or so to get it idling smoothly but it still bothers me about the poor mpg. I've given up practising feather-foot driving and find myself gunning it in frustration just to keep up with micra's!!

Post by **CitroJim** » 13 Jul 2007, 17:23

Both your hunting (absolutely the correct term

) and white smoke is precisely what I'd expect on 100% veg oil Mike.

I'm still mystified by this lack of power and low economy. I've been out in my TD a bit recently and it flies. It is very lively and I'm comparing it with an Activa here

The last thing left is timing. This is very critical on a diesel and I'd be very tempted to pay a visit to your local Diesel Specialist (every town has one tucked away somewhere) and have them run a timing check. It could be money well spent.

I cannot recall at this point if you have checked for the correct functioning of your Needle Lift Sensor but I'm sure you have. If not disconnect it whilst the engine is running and listen for a change in engine note. If none then that is your problem.

Xaccers · Post by **Xaccers** » 13 Jul 2007, 19:02

Interestingly enough, I disconnected the battery on Dex today while I was busy with other things, left it off for about 5 hours, hoping it would reset the ECU as my 2.1TD has been pitifully sluggish at times (took Cassy out very naughtily just to clean the brake discs and she's got so much oomph in comparison!).
Now seems to have a new lease of life, have to go for a good thrash in a bit.
The previous owner was a family man, with a disabled child, so I can't imagine him driving the car at anything other than sedate speeds, and I think the ECU learnt that way of driving (totally different to my "lets have fun" style

)
Will see how she goes.
Using 100% SVO in Cassy, I found giving it two lots of glow plug heating helped with the early morning starts, as well as a dose of redex every few tank fulls.

MikeT · Post by **MikeT** » 13 Jul 2007, 20:10

citrojim wrote:I'm still mystified by this lack of power and low economy.....The last thing left is timing.

With my limited knowledge I know there's more to eliminate than the timing. I think the inlets are probably goo'ed up from the EGR and lack of timely maintenance - including the turbo & intercooler. I found loose inlet clips galore when I first got this car and I suspect the hard-to-get-to areas are no different. I suspect sludge and deposits have built up in the oilways and the turbo suffers as a consequence. At 119K the injectors could be well past their use-by date.

citrojim wrote:I cannot recall at this point if you have checked for the correct functioning of your Needle Lift Sensor

No, that hasn't been tested, will try it next time. Thanks Jim

MikeT · Post by **MikeT** » 13 Jul 2007, 20:27

Xac wrote:Interestingly enough, I disconnected the battery on Dex today while I was busy with other things, left it off for about 5 hours, hoping it would reset the ECU... Now seems to have a new lease of life

I do that to my Ford, is it possible with the 1.9TD or isn't the ECU that complex on my car?

Xac wrote:Using 100% SVO in Cassy, I found giving it two lots of glow plug heating helped with the early morning starts, as well as a dose of redex every few tank fulls.

I thought about adding as much heat as possible and left it this morning for two full cycles - it always starts first time - but it made no noticeable difference, not to worry though.

I did wonder if it's worth putting any additives in the tank but one hears conflicting stories of what's good and works. I'll give it go - does the diesel redex smoke like the petrol one does? 8)

MikeT · Post by **MikeT** » 14 Jul 2007, 14:59

Yesterday I decreased the spring pressure for the on-boost fuelling inside the diaphragm but it didn't seem to improve anything.

As I had the throttle potentiometer off I gave that a good soaking in WD40 then contact cleaner only to find the fat gasket/spacer it sits on has broken at one side. Does anyone know the function of this gasket/spacer and if I should buy a new one as I've just put it back together for now?

Today, I tightened the intercooler hose clips and found the car pulling a little better, noticeably after 3Krpm and right through to 4.5K.

Again, I find the requirement to tighten up the clips overtight as an indication the hoses are not sealing well enough though someone on this forum (sorry, cant' recall who) told me it's normal for them to weep a little of the crankcase mist from the inlet hoses.

MikeT · Post by **MikeT** » 14 Jul 2007, 15:04

citrojim wrote:I cannot recall at this point if you have checked for the correct functioning of your Needle Lift Sensor but I'm sure you have. If not disconnect it whilst the engine is running and listen for a change in engine note. If none then that is your problem.

I took a cursory glance over the injectors but couldn't identify any connectors I could remove.

MikeT · Post by **MikeT** » 19 Jul 2007, 17:29

$\:D/$ I got black smoke $\:D/$

I can now do a Red Arrow impression at will (or could if I dyed the fuel

) now it's more like a diesel locomotive.

My latest changes involved decreasing the spring pressure (star wheel) clockwise 180 degrees and rotating the plunger diaphragm clockwise 90 degrees.

Additionally, the power increase is most noticeable when revved hard although the low down torque still seems pretty lame - anything below 2K.

Considering the original lean fuelling and poor mpg I'm guessing the injectors (120K on the clock now) may need renovating/replacing.

I've seen a pictorial of how to change the injector needles, can these be bought cheaply and is the job as easy as it seems?

If not, what are the current costs for such a job and do poor injector spray patterns lower the mpg significantly?

Thanks again for everyone's help in getting me this far, I'm pleased to know that I can now safely overtake the local rolling roadblocks. I even outdragged a Fiesta today

Post by **CitroJim** » 19 Jul 2007, 17:41

Good stuff Mike

Injectors are not that hard to service but there are cautions. Yes, the needles could be replaced quite easily and I'm sure your local Diesel Specialist would be happy to supply them but there is more to it than just replacing needles

If you pull an injector apart you'll see there are shims above the spring. This sets the point (pressure) at which injection commences and this must be balanced across all four of them. Changing needles is bound to affect their calibration.

Injectors also have to be checked for spray pattern. Both the spray pattern test and pressure test is carried out on the same machine which is essentially a hand pump with a pressure gauge on it and a perspex covered spraying area. Diesel is not used due to health risks associated with high pressure diesel spraying around. Instead, a special test oil is used.

The main point of the spray test is to check eveness and atomisation and to ensure there are no drips at the end of injection indicating a poor needle seal.

Sorry I missed you previous question Mike. If you look at No.3 Injector you should see a thin wire running from it to a connector block on your cam cover. This is the Needle Lift sensor wiring. It detects start of injection by sensing when the injector needle lifts off its seat.

If you disconnect it your engine note should change quite markedly.

Post by **CitroJim** » 19 Jul 2007, 17:46

MikeT wrote:Considering the original lean fuelling and poor mpg I'm guessing the injectors (120K on the clock now) may need renovating/replacing.

If not, what are the current costs for such a job and do poor injector spray patterns lower the mpg significantly?

Last time I enquired back in 2002 it was around £50 for a test, overhaul and recalibration if you took them out and gave them the bare injectors. I guess it'll have risen a bit since

Yes, worn, drippy injectors will do no favours for MPG or power. If they're drippy though they normally cause the engine to be a bit on the smoky side.

MikeT · Post by **MikeT** » 19 Jul 2007, 18:11

citrojim wrote:...Changing needles is bound to affect their calibration.
Both the spray pattern test and pressure test....

Oh, ok

If you look at No.3 Injector...This is the Needle Lift sensor wiring

I'll take a closer look at No.3 (from the left or right?

) but are you sure my mechanically pumped fuel system has one? I read the BX guide on diesel fuelling and it implies the sensor is only for the full blown ECU controlled fuelling.

Post by **CitroJim** » 19 Jul 2007, 20:01

No.1 Cylinder on all XU(D) engines is totally against standard convention Mike and is nearest the clutch. No.4 on an XU(D) is nearest the cambelt where you'd expect No.1 to be on any other engine

That's French for you

A '98 Xantia certainly should have a semi-electronic pump. Does it have a pot with three wires emerging from it on top of the pump Mike? If so then it'll have a needle lift sensor.

Otherwise there is something strange with yours. Fully mechanical ended in 1995 as far as I know. It'll be worth checking Mike as you may have a non-standard pump and hence all your issues....