306 TD black smoke and power loss

jgra1 · Post by **jgra1** » 11 Jun 2010, 21:40

All, a friends td has just started suffering black smoke and low power.
A brief history... car brought and used for a couple of years, I have done very little to it except changing the lucas system to a bosch, and since then it has - like my xantia - ran on WVO form the same source.. It has always suprised me as being a very nippy car, a lot more lively than the xant.. it sounds like a tighter engine and rev happy and almost fun

but yesterday, I got a complain of no power, reems of black and panic.. I went to the car tonight, started it, checked the obvious things and then drove it.. for a few seconds it performed as always, then sure enough it lost the lively edge, and was smoking black.. the good news is that its still a quick car, but only for a short time.. any thoughts?
It had a drop of injector cleaner recently and a tank of diesel..

I can only imagine fuel starvation but cant see how that will smoke?

John

hmmm edit...

I cant remember if I removed the EGR.... 99% sure I did..

edit..

81% now...

Post by **CitroJim** » 11 Jun 2010, 22:01

Hi John,

Moved it to the Peugeot section

Hope you don't mind.

Black smoke is a lack of air or an excess of fuel.

I'd look at the former first. One real favourite is the rubber intercooler pipes collapsing and squashing flat under boost.

Another cause could be a wastegate sticking wide open causing the turbo not to spin very fast and starving the engine of air.

Turbo might be starved of oil and seizing when hot maybe although I'd have thought unlikely.

Blocked air cleaner? A lump of roadkill in the air intake?

Overfuelling could be caused by a punctured LDA (UFO) diaphragm in the pump. Try disconnecting the boost sense pipe from it.

How's the LPG conversion coming along?

evilally · Post by **evilally** » 11 Jun 2010, 22:12

Strangely, air ingress causes smoke. If you have power for a short time it adds up that as you draw more fuel, you increase the vacuum on the system, and start to draw in air. It would take a few seconds for the air bubbles to hit the injectors, at which point you would get power loss.

I would get yourself some lengths of clear fuel line, install them between the fuel system components and watch for air bubbles when you give it some revs. £10 says it's the fuel filter housing, another possible culprit is the primer bulb which is prone to perishing with age and veg use. You can also use a tyre inflator to put the fuel line under some pressure and listen for air escaping.

My second suggestion would be that you are bleeding boost somewhere, but I don't see how you would retain power for a short time for it to drop off suddenly. Give it lots of revs and listen for any strange whisteling noises in the engine bay. A common one is the seal between the intercooler and inlet manifold blowing out.

jgra1 · Post by **jgra1** » 11 Jun 2010, 22:27

thanks both

Jim LPG taken a back seat because of the impending barn build , pics over weekend of my autocad idea.. feel free to poke at the holes in my design

Ally yes the fact it ran perfectly for a good blast is the key. Jim, checked air intake and turbo pipes briefly and all is ok.. car is very quick, for a bit..

Clear pipes are a great idea for the next diagnosis..

jgra1 · Post by **jgra1** » 21 Jun 2010, 21:39

chaps I need a bit of help here.. sure its something easy..

quick history..

the ladies 306 td has been running well for a year or so on WVO.. I did the lucas to Bosch myself.. recently I advised her to do some tunisian tuneups (tm) before the MOT, and also to add a bottle of injector cleaner just in case..she also fille dit with Derv for the first time in a while (normally 50/50) the car passed fine, but then very suddenly starting black smoking and was down on power..

I drove it briefly and it was fine for a few seconds, full power, then it settled into chugging (edit its runs very clean, just blasts the floor with smoke on anything other than no throttle) and has not changed in a week..

Tonight it arrrived on my doorstep, and I had a rushed hour to see what I could find out..

Airfilter looked ok (she got one for a non turbo, so i couldn't fit it)

- I disconected the intake system behind the nearside corner of IC, and that made no difference..

I ran the car breifly without the IC connected and no difference (only at standstill)

I marked and rotated the IP both directions (the car sounded far to nice to be timed right) and no difference

I replaced/fixed a broken IC-IP boost pipe (could have split tonight not sure) no difference

I made sure there was rushing air from the Turbo to intercooler pipe

I took the flying saucer off the IP, oil in there, cleaned that up, and made sure the actuator went down and sprang back ok.. standstill testing with this up or down produced little or much smoke as expected?

I can only think of two other possibilities.. an injector is now blocked because of the cleaner that went through (but why is the car quiet)*

Something has gone awry in the IP..

*the car is and has always been a lot nicer and quiter than mine.. and it's been much more powerful although it is a 306 not a xant.. there is a hint of knocking maybe, on acceleration, but nothing that I would expect from a blocked injector..

she has a ferry to france booked, and i have no time to do much with it

thoughts...

John

evilally · Post by **evilally** » 21 Jun 2010, 22:10

I would seriously look into air ingress, my 405 did exactly the same thing, power loss, lots of smoke. I also know what these engines are like with no boost being produced. They smoke, but will continue to rev through the range. With air ingress you sort of hit a brick wall.

Try a bit of clear line before the injector pump and give it some welly for a few seconds and look for bubbles. It's also worth putting a bit of clear line after the pump on the return line, this will tell you if there's a faulty seal in the pump.

citronut · Post by **citronut** » 21 Jun 2010, 22:18

have you checked the fuel filter, someone i know used to have a 1.9 D falicia running on bio from Rye oil's, every now and then it would not run very well at all, the last time i fitted a new fuel filter the old one was gunged up solid with sludge,

regards malcolm

jgra1 · Post by **jgra1** » 21 Jun 2010, 22:25

thanks both

sorry forgot to mention

clear pipe fitted tonight, no bubbles at all (only fitted between filter and pump) noted ally

good new fuel filter was replaced with a brand new one last week..

jgra1 · Post by **jgra1** » 22 Jun 2010, 09:41

can anyone think of anything else I can do or test ? the significant thing is that the car seemed to run perfectly for 20-30 seconds last week.. the symptoms seem almost like a petrol car flooding.. overfueling... almost..

there is air, turbo.. it only leaves the pump ?.. can I quickly get into it to find anything else out..

thanks as always
John

jgra1 · Post by **jgra1** » 22 Jun 2010, 10:27

quick question..

if the boost was low, then the boost fueling device (sorry rubbish terminology) would not work either? so it wouldn't overfuel or smoke, just be low on power.. ?

jgra1 · Post by **jgra1** » 22 Jun 2010, 12:39

fixed.. nothing to do with me.. she drives it too slowly.... is my take on it..

the email based on the conversation the garage guy gave her...

Chris has sorted it quite and quite quickly actually. He checked various things, put the pump timing back and said there was a lot of build up in the actual exhaust from how it has been running recently. Basically it has been O/D ing on veg oil which meant that the flashpoint wasn't high enough and it got clogged up (that's my wording from which you can hopefully work out what he actually did). He gave it a good hard drive told me to fill up with diesel and put in 600ml of injector clearing fluid in. He says it is almost clear now and will get clearer as I burn the diesel. Also said go easy on the veg oil until it has stablized and had a good long drive, the trip to France should do it.