White smoke and heavy vibration - 1.4 tdi ATL

Un4tural

Member
So I feel it is time to poke the collective mind on this one.

Long story short, I've swapped engine for a low miles ATL motor, with blown turbo (100k)

It is all good, no fault codes, but it smokes quite heavily white/blueish smoke, it does not appear to be eating coolant as put 5L in from empty and it seems steady.

Replaced injector #2 with fresh seals as glowplug was quite wet, seemingly with fuel - but it is still same, clear of fault codes though.

injector quantity deviation of 2.99mg/h for #2 and -3.01mg/h for #3 - but I am not quite sure what to make of it now, has to be something mechanical ECU cannot quite make out. (cyl1 deviation is -0.19)

giving a rev vibration stops and it stables out roughly at 2k rpm but I don't particularly want to take it on a drive to see if it shakes itself to death.

I would've suspected cyl2 would have had a fair bit of fuel in there, but surely it would've burned off in 10-15min? As seals were definitely perished. I should probably have done all 3 but other 2 glowplugs seemed perfectly normal with a bit of white crust on them, as I'd expect.

Cams seem to move alright but i get a bit flow blowback in intake as well...

It is a somewhat mystery box, so open to suggestions. Will probably end up taking all 3 injectors out and putting known good ones out of my old motor?

It feels like engine is turning a ballast around when idling, which goes away at higher RPM.

It fires up right away after cranking fuel in following the injector swap, though it does not really sound like a 3cyl. Prior to injector it'd tend to crank a bit longer, presumably as fuel was leaking through the seals.
 

Un4tural

Member
Connections and loom in crank case seemed in good nick, but I might try one from old motor just in case or go over with multimeter to make sure wires aren't broken. Hoping it is not head gasket but I have no way to check that I can think of.

Edit - Will give connections a one over - if it was poor connection ECU would report something injector related though surely?
 

audifan

A2OC Donor
My fear is in the original problem the engine had. A blown turbo. Have you checked the engine for injested parts i.e. had the head off. Have you done a compression check? Is the engine mechanically still timed? Balance shaft ok? Did you swap an AMF or BHC for the ATL or was it an ATL already?
 

Un4tural

Member
My fear is in the original problem the engine had. A blown turbo. Have you checked the engine for injested parts i.e. had the head off. Have you done a compression check? Is the engine mechanically still timed? Balance shaft ok? Did you swap an AMF or BHC for the ATL or was it an ATL already?

Swap was atl for atl.

Timing seemed fine, I cannot say about balance shaft. But I will have a good list to go over. Hoping to not need to take engine out though for a full rebuild just yet though.

I shall also order a compression tester.

Definitely no turbo bits ingested, it broke off exhaust end and made quite a chunky indent on exhaust end housing though, intake side was in one piece with no broken fins.

EDIT: to add - looks exactly like this, but doesn't improve as it goes warm -

I'll go do the loom and connections first when I have some daylight.

No codes oddly enough though.
 
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Un4tural

Member
Bloody Freezing out! Journey continues - bought a compression tester so will go check later.

Replaced all 3 injectors at this point as was there, seals were not great, but other than #2 they seemed tolerable thought #3 was gunked up really bad with carbon. Cleaned up all the connections and those should be fine but it is same, white smoke out the exhaust and it rattled like the PD in above video.

will go over compression/timing later to make sure it is spot on, just in case, following that and depending on results I am guessing I'll make way to going half in the motor and see what it looks like with the top off... water gone down a little bit in expansion tank but it could still be just filling in any air pockets, as i haven't fully ran it to temp yet due to said vibration.

Need to check the fuel trim etc. too and see if that has changed at all.
 

Olerype

Member
What I have read is that injector seals must be replaced every time they are out. Does the injector fit firmly? Have you fitted the injectors correctly?

Do you know when DMF was replaced? That cured at lot of the vibrations at standstill.

Do you know the service history? Using wrong oil or overrun the service intervals I have read may worn out the camshaft lobes so the fuel timing will be totally wrong.

I have a similar problem with my ATL; it shakes at acceleration

 

Howey

Member
Are the injector wiring connections tight? The plugs shouldnt wobble when connected mine was barely driveable when mine has become a loose fit

Flywheel can cause injectors to try and balance a vibrating engine (in general)

Coolant temp sensor can cause overfueling but wouldnt have thought it would generate such large discrepencies with the injectors more a uniform overfueling
 

Un4tural

Member
I have gone over the injector connectors and pinched with pliers, all seem nice and connected. Injectors nice and jammed in there, new seals covered in bit of oil for ease of entry. All 3 injectors known working from my old engine, with all new seals, re-adjusted according to instructions, though I feel i want to read up more on how they work, presumably camshaft presses it to give it more fuel pressure? as injection itself is electronically controller? but not to go off topic too much.

I am worried it is something deeper in the bowels of the engine, as really don't want to go taking everything off again, as read quite a few instances of cam rods bending when turbo goes on these 3pots - they seem to move up and down okay however and looking around with rocker cover off everything looks lovely, doesn't even have a black tinge to the metal like my old motor, nice yellowish oily goodness.

On my to do next will be to check VCDS readings and then compression test and go double check all the timing I guess, see where I am then.
 

DuncanA2

Member
As for the injection quantity deviation, it is alright for negative compensation. The negative deviation compensates for the positive IQ which is at fault here. This could PD-injector related, but as you stated they should be fine. What I didn't read is whether there has been a compression test conducted? The volume of the injection is also dependant on compression and based on the downward force on the crankshaft meassured by the Crankshaft sensor. In order to balance out for smooth idling, this could be something to rule out.

Cheers Duncan
 

Un4tural

Member
Compression tool only turned up few days ago so not had the chance just yet and I didn't want to run it to do scans and check values as was pretty calm and it smokes a ton.

Thought it was possibly compensating for cyl 3, but from what I gather for it to be that high something has to be pretty wrong, engine really wobbles like an unbalanced wheel, i'll try and get a video if i have daylight, revving it smooths out the vibration but smoke just gets worse.

Not sure how long it takes for extra fuel in cylinder to burn off, but cyl3 injector had quite a chunk of carbon buildup on it, possibly why took me good 1-1.5hrs to get it out too, looked pretty nasty.

It annoys me that I have no fault codes too - if timing was out enough for it to run this poorly it would surely give me implausible signal or similar.

Anyways, I'll go dig deeper when I run into some daylight and favourable weather and update - worst case i'll go figure out if AMF/BHC head is compatible i guess.
 

kp 115

Member
Compression tool only turned up few days ago so not had the chance just yet and I didn't want to run it to do scans and check values as was pretty calm and it smokes a ton.

Thought it was possibly compensating for cyl 3, but from what I gather for it to be that high something has to be pretty wrong, engine really wobbles like an unbalanced wheel, i'll try and get a video if i have daylight, revving it smooths out the vibration but smoke just gets worse.

Not sure how long it takes for extra fuel in cylinder to burn off, but cyl3 injector had quite a chunk of carbon buildup on it, possibly why took me good 1-1.5hrs to get it out too, looked pretty nasty.

It annoys me that I have no fault codes too - if timing was out enough for it to run this poorly it would surely give me implausible signal or similar.

Anyways, I'll go dig deeper when I run into some daylight and favourable weather and update - worst case i'll go figure out if AMF/BHC head is compatible i guess.
Hi Un4tural,
When you set the injectors in position did you set them to the dimensions given in the detail or square to the head?
Hth
Keith.
 

TAABVW

Member
I think the clue here is no fault codes. So you are looking for something mechanical.

I once carelessly fit a timing belt on a 4 cylinder TDI one tooth out. It idled like it was on three cylinders and smoked badly. I quickly realised my error and corrected. I remember being amazed at the time that it fired up at all with the belt one tooth out. Assuming injectors are fit correctly then I think you would get a fault code if they were the culprit.

Trevor
 

Un4tural

Member
Hi Un4tural,
When you set the injectors in position did you set them to the dimensions given in the detail or square to the head?
Hth
Keith.

Measured gap where they were from wall at connector, as did not have tool long enough to reference all 3 from side of block, tap it into place tenderly with the love mallet. Then followed process for adjusting the cam height on the adjustor screw on all 3 which seemed alright too.

@TAABVW I hope it is timing at this point and I just missed it when doing the look over, as was pretty toast at the time with engine swap.

Thanks all, gives me good stuff to look/think over like the loom, wouldn't have thought that might be a common failure point, on PDs in general too it seems.

Anyone had experience and have an idea how long it takes fuel to be burnt off? As probably half a shot glass gurgled down when the injector finally gave way and flew out, tried to rag as much of it as I could though.
 

Un4tural

Member
Cyl 2 has no compression it seems. Timing is fine, guessing one of the valves has bent when turbo went on this engine i got for replacement.

From what I've read top of the motor is same for AMF and BHC motors, matching ATL? if so i should be able to get top half of motor off any of these and fit?

Are there any other suitable candidates from Polos etc.? gone this far might as well go for a headgasket and top of engine rebuild... or even potential minor upgrades?

Also if you are going for engine from a "known running" car, the 50£ compression tester is totally worth the money.
 
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Howey

Member
Think polo has a different sump

Afaik the 75 and 90 engines are the same its the turbo and injectors that make the difference and i think the 90 has an egr cooler and electronic throttle body like the later 75? But i am not an expert by any means!!
 

Robin_Cox

Member

At the head end there are some small differences between AMF / BHC / ATL - most prominently early AMF had slightly longer valves (higher lift?) than late ones (same as BHC & ATL) on the same camshaft based on that parts diagram, but that apart my guess would be they should be interchangeable. Aren't there also AMF / BNV / BNM from roughly contemporary VW / Skoda vehicles.

 

DuncanA2

Member
Cyl 2 has no compression it seems. Timing is fine, guessing one of the valves has bent when turbo went on this engine i got for replacement.

From what I've read top of the motor is same for AMF and BHC motors, matching ATL? if so i should be able to get top half of motor off any of these and fit?

Are there any other suitable candidates from Polos etc.? gone this far might as well go for a headgasket and top of engine rebuild... or even potential minor upgrades?

Hi Loss of compressuon is consistent with the IQ of the #2 cylinder, being +2,99 and cylinder #3 was compensating for it. This as mentionend in you earlier post. I think you have the culprit there. 👍
 
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