No Black Smoke

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jeremy
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Post by jeremy »

It may be the injectors are worn - its sounds a bit like my BX before they were changed - which transformed the car. Other symptoms were smelly exhaust and some excess smoke especially at startup and - as the MOT inspector claimed - at all other times.
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MikeT
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Post by MikeT »

I "repaired" the boost-to-pump pipe, it was deteriorating at the pump end. The rest of the pipe looked good but I will replace it with new at some point soon.

The clips came off easily with a twist of the screwdriver blade, and went back on with a slight struggle using pliers to squeeze and screwdriver blade to steer.

It may be imagination but I think the repair has made a small difference. But I still can't see black smoke.

How easy is it to rig up a turbo boost pressure meter for testing?

Do worn/dirty injectors affect performance this way? (Did I read that veg oil will clean the fuel system?)

Incidentally, I've noticed a dead spot in the acceleration at appx 2.4Krpm. It's like something cuts the engine very briefly and as the momentum carries it over the dead spot, it continues accelerating as usual.
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Post by Xaccers »

MikeT wrote: Incidentally, I've noticed a dead spot in the acceleration at appx 2.4Krpm. It's like something cuts the engine very briefly and as the momentum carries it over the dead spot, it continues accelerating as usual.
A-ha!!
My 2.1TD is doing something like that, varies between 2,400rpm and 3,300rpm ish
Like it stutters.
Have yet to find time to investigate, but I know I'm getting air into the fuel line from somewhere.

Check your leakoff pipes (the rubber ones between the injectors, last one will have a cap) and if they're hard or cracked, replace them.
Halfrauds do a kit of a length of pipe you cut up and two caps for a reasonable price.
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Post by xf8u »

My 1997 2.1 SX is a superb car. It is quieter than a 1.9 and more responsive and powerful due to its computerized pump.
I had a Y reg 2.0HDi(90) a while back but I rate the 2.1 more.
Just one thing, don't put veggie oil in a 2.1
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Post by MikeT »

Xac wrote:
...Have yet to find time to investigate, but I know I'm getting air into the fuel line from somewhere.

Check your leakoff pipes..
Hi Xac,
I saw bubbles in my fuel and as I have the Bosch pump, bought a pre-cut 1M length of braided-reinforced leak-off pipe from my local motorist discount store for £1.75. Cured the air-in-the-fuel leak and consequently, the hot start problem.

Personally, and I'm guessing, I think this dead-spot problem may be related to the accelerator position sensor.
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Post by Xaccers »

xf8u wrote:My 1997 2.1 SX is a superb car. It is quieter than a 1.9 and more responsive and powerful due to its computerized pump.
I had a Y reg 2.0HDi(90) a while back but I rate the 2.1 more.
Just one thing, don't put veggie oil in a 2.1
Wish mine was more responsive than my 1.9TD.
If my gf wasn't kicking up such a fuss about keeping the 2.1 rather than the 1.9, I'd be really tempted to keep it because it goes so well and of course, runs lovely on veg which the 2.1 can't (rassum frassum stupid lucas).
Agree on the 2.0HDi, mum's got one in a Xsara and it's gutless.

Thinking about maybe writing to the previous owner to see if they knew of any issues when they had the 2.1
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Post by JohnCKL »

I have a dead spot just before 2000rpm in 3rd gear. Always wondered what it was. Just a moment's hesitation in acceleration before continuation.

For black smoke and more power, easy, just tweak the fuel pump. On the right side of pump is the power adjustment screw, turn it clockwise 45 degrees should give ample power. Top of the fuel pump, on the flying saucer thingy, is the smoke adjustment screw. Remove the top cover if its still covered, loosen the nut, and screw in 2 full turns and your 1st gear should have better acceleration and some black smoke. There are 2 more tweaks inside the UFO, one where you turn the plunger clockwise, 45 degrees would give good power and the star wheel adjustment below it, I turned it half turn clockwise for quicker fuel delivery. Remember to mark the point where the original position of the plunger and star wheel is. In of the these threads, there's a good website on tweaking the fuel pump with diagrams, do a search on diesel tuning.

Here's the website, http://dodgeram.org/tech/dsl/more_power/Power_ve.htm
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Post by MikeT »

Thanks JohnCKL, I'll study the info later and report back, looks most interesting.
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Post by MikeT »

Having read quite a bit about diesel tuning, I have to say I'm still none the wiser really. It seems there are numerous tweaks to do with the fuel pump and one or two to the turbo.

I remain cautious as it's evident you need proper monitoring equipment to get optimum settings for power, economy, reliability and last [but not least] emissions. To create black smoke and "turn it back a bit" is not really scientific enough for me :lol:

I liked the idea of increasing non-boost fuelling though, so increased mine one turn [1.5 to 2 turns seems to be the concensus].

With urban driving I did notice a subtle difference. First I thought the engine was maybe slightly over-reving or I realised I was cruising and/or rolling-on slightly faster than I normally approach speed limits or hazards.

I haven't seen any black smoke yet so I'm encouraged to increase it by another half to one turn - should be fun.

Am I right in assuming the turbo won't respond well to tuning if it's limited by the fuel supply? Ergo, tune the fuelling first?

And by the way, I hope I'm not missing something here but 50% vegetable oil should give black smoke too, right?
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Post by Xaccers »

My 1.9TD rarely smoked (apart from when the timing was slightly off and it had really old veg oil, then it really smoked, and sparked!)
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Post by MikeT »

JohnCKL wrote:
For black smoke and more power, easy, just tweak the fuel pump.
I took a look but can't see the power screw. Is it behind the balck plastic cover which has wiring attached?
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Post by MikeT »

Xac wrote:My 1.9TD rarely smoked (apart from when the timing was slightly off and it had really old veg oil, then it really smoked, and sparked!)
Did it pong? :lol:

I was more wondering if veg oil smokes black like diesel can when over fuelled?
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Post by Xaccers »

MikeT wrote:
Xac wrote:My 1.9TD rarely smoked (apart from when the timing was slightly off and it had really old veg oil, then it really smoked, and sparked!)
Did it pong? :lol:

I was more wondering if veg oil smokes black like diesel can when over fuelled?
It apparently smelled like a chip shop but in a nice way :D

The only smoke from it was white from what I recall.
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Post by JohnCKL »

"Am I right in assuming the turbo won't respond well to tuning if it's limited by the fuel supply? Ergo, tune the fuelling first?"
Yes, previously tuned the max fuel, smoke limiter n turned the turbo wastegate to the max, got only 1 bar (14.5psi) from 0.8 (11.5psi) untuned. Now tuned the diaphram spindle n toothed wheel n detuned the smoke limiter, got 1.1 bar (16psi) max out n much more responsive engine, a little more smoke n i think even better mileage.

"I took a look but can't see the power screw. Is it behind the balck plastic cover which has wiring attached?"
Its at the top right side of the wiring, probably with a tamper proof cover. Mine is without the cover, so can't tell you how the cover looks like or how to remove it. This power screw is very sensitive, only turn it 10-20 degrees clockwise at a time up to 60 degrees n you will see black smoke n your idling up. I only turned mine about 40 degrees. remember to loosen the locknut 1st.
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Post by MikeT »

[quote="JohnCKL..Its at the top right side of the wiring, probably with a tamper proof cover.[/quote]

I'll take a proper look another day, got to investigate a leak first :oops:
Cheers
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