fixed 1796 but now misfire cylinder 3 fault code

[vwnewbie]

2002, golf, 1.9 tdi turbo, 200kmiles

Thanks to posters here, I fixed the low boost fault by finding a split hose BUT the car worked for 5 mins BEAUTIFULLY and then nearly blew up.

Details: After fixing the low boost, took the car for a spin; it was like a racing car. I changed into 4th and NOW I could still have acceleration above 2200 RPM. Also had the boost back in 5th gear too and the flat spot had gone. Felt like I had another 100 horses.

But after 3 mins, I was doing about 50mph to 60mph in 4th or 5th (can't remember) and about 2500 RPM (I don't normally rev that high, I was just checking that the flat spot had gone - (which occurred in 4th and 5th gear at 2200 RPM)), THEN the revs went SKY HIGH (thought I had a runaway turbo for a second) and loads of grey smoke and a knocking noise. Clutch engaged, ignition off, bump start and got home.

Drove sluggishly below 2100 rpm in any gear with blue smoke but drove well (with turbo sounding ok) above 2100 rpm and no smoke.

Fault code CYLINDER 3 misfire.

Any idea what has happened? I 'fixed' the split hose temporarily for the test with tape (now has new pipe though). Did the hose collapse and give me NO vacuum to any of the hoses and cause the huge symptoms described?
What would have caused the massive revs and smoke? What have I damaged? Where should I start looking?

Thinking I will renew all hoses and test injector loom to begin with...?

Thanks if you can help at all,
George

[vwcabriolet1971]

excess oil will lead to a diesel engine burning it's own oil as fuel ( hence excess revs) and frothing of the oil ( which is not a good lubricant or cooling agent). Some oil will be burnt on the valves and piston crowns causing pre-ignition and reduced airflow. Various other unwelcome things may happen ( possible cyl. gasket blowing ) and injector fouling ( carbon from burnt oil ).
All in all not a good thing to do. The severity of problems is proportion to the amount of excess oil.

[vwnewbie]

Many thanks.

Looks like all is not lost and I may have a chance of reviving the old girl.

cheers

[vwnewbie]

My car is smoking like this one (although mine is not going on a road):

Idiot driving his Golf TDI with broken turbo - YouTube

Found out that 0.5 litres had been added when dipstick showed BELOW minimum.
Having spent ages searching and reading, the excessive oil from exhaust and poor running could be from an:

the point you make
imbalance of vacuum hoses on turbo (remember I found one split hose and all problems occurred after I replaced hose (but did not check others)
blown turbo
Breakdown recovery man thinks cracked piston (he just looked at smoke and stated that ! I can check that with a compression test.

So, I will do each of the following and then test car (unless you guys say otherwise):

replace all hoses see if that does anything

take injectors out and do compression test. Test wiring loom

Squirt some turbo cleaner into turbo whilst in situ

Take turbo off and examine

How To Replace A Turbocharger - YouTube

Mr Muscle TDi Turbo Sticky Vanes Clean - VW / Audi / Seat / Skoda - YouTube

[vwnewbie]

UPDATE:


This may be the main question, but see what you think after reading my post (sorry for length) How could fixing the boost and therefore the variable vanes, thus making the turbo work properly suddenly cause this MASSIVE and continual oil burn?

Did a compression test (sort of)...

I have only had a diesel for 2.5 months and it has been a steep learning curve (but enjoyable).

SHORT STORY first: All cylinders produce the same compression. No oil etc was blown out. BUT I did the test on cold engine (because I had taken a few bits and pieces off and it was raining so I had to be quick.


LONG STORY
The compression tester I have was my grandfather's so circa 1950. Just a tapered rubber seal bung on end. Too big to for small glow plug hole. So I took the big bung on and pipe was too small to make a seal. So I cut a bit of new vacuum pipe and attached to end of compression tester.




Now, this did not make a perfect seal, but as I said I received identical compressions, BUT the reading was only 100psi (400 psi is expected I think).


I stuck my finger over each hole and it was blown off (the glow plug hole, not my knuckle ) and not sucked into the gp hole too much.


I will use the lathe to turn an adapter to fit the glow plug hole and compression tester and re-do test on warm engine, but...


... am I right to be mildly optimistic?


Trying to figure out how oil was burnt now.


This video shows a turbo re-build. There do not appear to be many seals. I will be taking mine off (if after doing a boost leak test and physically seeing if there is any play on the shaft I find something amiss).


But where is the seal that stop the lubricating oil entering either side of the spindle?


Would a new CHRA be a way to go IF I find all the trouble is down to a duff turbo?


https://youtu.be/3CVIrfK2Z7I?t=427


I have also concluded that this car has not been cared for. The whole trouble I have learned is owing to a low boost fault (owner said turning engine off and on fixed his "poorly injector"). Don't know how long he had been doing that, but I had been doing what he said for 2.5 months and maybe 700 miles until I found it was a simple split in the hose the the turbo actuator for the variable fins.


Upon fixing that split hose, car went like a rocket for 3 mins, then the big smoke blow out (but engine did turn off via ignition, (so not a runaway?)


Still need to do a leak down test (Haynes manual won't tell me how (professionals only), but I will learn.


I will try to clean the turbo in situ (just remove exhaust pipe) in case of sticky vanes, but that would only cause low boost, not the burnt smoke.




How could fixing the boost and therefore the variable vanes, thus making the turbo work properly suddenly cause this MASSIVE and continual oil burn?