R520 Cold start smoke and stutter

But white smoke and slow start isn't always just mechanical timing....
M1ketdi gave me a clear answer in one sentence!
As I said its not a 15 min job on mine....
But I do appreciate all replies

It's not always, but it usually is..

What's so special about yours? I can adjust pump timing on an ALH and an AHU in 15 minutes.. the AFN can't be that much different than either of those..

Rise the idle at 1000-1050rpm when engine are cold...




Dieseleux

Longitudinal engine means bumper off, front carrier moved forwards into service position before I can even consider getting cambelt cover off. Not the end of the world, just makes things take a while

bhodgkiss said:

Longitudinal engine means bumper off, front carrier moved forwards into service position before I can even consider getting cambelt cover off. Not the end of the world, just makes things take a while

Click to expand...

LOL no. its even easier on longitudinal than transverse!

I have changed a cam without going into service position on mine!

hmmm i shall take a closer look then! There's enough room to get the cambelt cover off and then a tool to undo the pulley bolts and torque back up???

bhodgkiss said:

hmmm i shall take a closer look then! There's enough room to get the cambelt cover off and then a tool to undo the pulley bolts and torque back up???

Click to expand...

Well you can't do much wrenching from your office chair/couch, sometimes you have to get your hands dirty.

my hands are regularly covered in motor oil, dont worry about that
Just didn't think access was possible.

Just surprised so many people have gone to the trouble of removing bumper, sliding front carrier forward/removed completely when its not required??

Just looked Jon and as you say there is room down the front, so just enough to get the Cambelt cover off by the sounds of things! Will give it a go.

Car is certainly much quicker, took some logs tonight and 30-60 times down to sub 5 seconds now
It's starting to slip the clutch if I plant it at 2000rpm so will take it easy before the SRE clutch goes on.
Something is still limiting the fuel though:

I ask for 60mg.
The two limiters will limit to 59mg
(The vcds maf reading shows enough air)

But I get 57.6mg max......

This correlates with 1000mg of air in the MAF smoke limiter map.
Is my MAF now maxing out and limiting fuel?? I didn't think it would?
Pump voltage is at 3.4v in the map or 4.1v in vcds (1.21x factor) so not maxing this out.

I had this before the r520's too where something was limiting fuel. But I thought this was the pump reaching its max as it was getting to 4.44v (or 3.65v in the map)? I've he's this is a limit?

Finally, timing is moving around more now than with stock injectors.... Is this normal please? For example it will be a degree under specified then jump to a degree over specified at high revs.

Thanks

Try logging pump voltage, n146....

I have channel 1 logged if this is what you mean?
Just attempted to adjust IQ adaptation in vcds.
I can only move it from 4.9 to 4.7mg/str

So ideally hammer mod required.
Although all running well, so not high priority ( especially as clutch is current limit anyway)

I have R520's. My physical timing is close to full advance (green line). mileage is 161k and I have an 11mm pump and lift pump.

I get some blueish white smoke on start up when cold (near freeze). start up is generally less than a second long after glow time

below freezing seems to start better than near freeze but I believe that is due to after glow

JFettig said:

LOL no. its even easier on longitudinal than transverse!

I have changed a cam without going into service position on mine!

Click to expand...

how can you get the viscus fan off without moving the rad ?

EDIT: or do you mean you just changed the cam , and not the belt ? , if so thats easy, i think the belt could be done too if it wasnt for that viscus fan

Why do you need to?

thought you ment change a belt with the front end still on

oh, no, do IP timing, cam swap, cam seal, etc with the front end on.

yea easy , loads of room

Hi guys

It's finally getting colder here
I've not adjusted my pump for more advance yet but want to this tomorrow, as struggling with cold starts again.....
Where on the pump are the bolts on the AFN to loosen it to rotate it please?
I can only see one obvious one?
Does the Cambelt cover need to come off?

Here is a pic are any visible?

Remove cambelt cover and look at the inj pully and you see the orther 2 nuts. Also under the pumphead there a bolt just loosen al bolts a bit start engine and tap it to side of engen to advance and away to lower timing.

Many thanks
So there are 4 nuts/bolts?

Jep 4 bolts to losen up

Perfect, just done this, a bit of plus gas loosened the pump from the mount plate, luckily got it spot on 1st time loosened and retightened the fuel lines too.
Top tip of the day to align the bolts behind the injector pulley is to crank the engine until they line up not much room to turn the engine over manually with the bumper on.
Will see if it's any better later when it's cold!

Nice you can also here if the timming is good ore to late. Wjen timing is late there almost no diesel nock. When turn the pump to engine side you here louder diesel nock.

start up smoke with tdi's seems to be a mystery. all seem to a bit, best to forget about it and drive on