misses and white smoke if i

[carrizog60]

rev it in neutral...

the alternator is diyng so i need to rev the engine so it catches and start recharging the battery.

problem is that sometimes it need more revs than normal and if revved higher sometimes the engine starts to miss and smoking white.
if you shut the engine,let it be and start it again all is normal,same thing if you just keep the foot in a steady,low rpm.

what could this be?something regarding lifters and boost?

the engine is a 1.9td with a vnt20 turbo.(it makes boost just revving)

[maxfax]

I think I'd start with checking the fuel filter, and for air leaks in the fuel lines.. 

[carrizog60]

all is good...

[maxfax]

Boost won't cause missing.  I'm still leaning towards a fuel issue.. Is it ever difficult to start?   Lifters holding the valves open at tad could cause such issues.. If left idle a bit w/o shutting it down will it clear up??

[carrizog60]

yep,if i rev just a bit so it wont shakes that hard it will return to normal after 5 seconds.

yesterday when i was adjusting my boost,after i revved it to check for smoke it did it again...
a "cracking" sound(cant explain) and then the shakes,misses and white smoke drama...

all is normal,starts very good,no smoke on regular driving and good power(went to a tarmak road near home and as soon as vanes open traction becomes an issue even on 3rd gear,and thatīs a passat with tdi gearbox)

if lifters why would that happen?
i once saw a peugeot 205td shooting flames from the exhaust just by revving in neutral and the engine didnt miss so its not normal...

[carrizog60]

it seems that it does that when cold.

[carrizog60]

 

[8v-of-fury]

Well fueling is every thing with these engines.. It controls every aspect of combustion, so it is usually the only suspect.

It only does it in neutral but not under load of any sorts? An interesting problem you have here.. I was gonna say the timing piston in the pump, but it would be apparent under load as well. Hmm STUMPED.

[R.O.R-2.0]

my audi used to do the same damn thing. and it would only do it in neutral.. and it would CRACK when you would rev it in neutral..

[carrizog60]

yep,i can hear a sort of cracking sound and then the engine stumbles...

could be lifters not acting correctly and a valve kissing piston due to not fast recovery?
on other hand that would not explain the stumble and white smoke...

it appears that with the vanes more closed it does more often,so it could also be with pressure related...

[R.O.R-2.0]

yep,i can hear a sort of cracking sound and then the engine stumbles...

could be lifters not acting correctly and a valve kissing piston due to not fast recovery?
on other hand that would not explain the stumble and white smoke...

it appears that with the vanes more closed it does more often,so it could also be with pressure related...

my audi has solid lifters..

i was leaning towards an injector issue on my audi..

it would miss/stumble, and CRACK while it was doing it..

it would also make a HUGE cloud of smoke while it was missing..

you could see that the smoke was only coming from a cylinder or 2, being as how it was pulsating coming out the exhaust..

[carrizog60]

did you ever had a certain of what it was?
from what you say is exactly what my car does,exeptit only makes the craking sound once...

[R.O.R-2.0]

did you ever had a certain of what it was?
from what you say is exactly what my car does,exeptit only makes the craking sound once...

no, i quit driving it, and never went any further.. the engine needs a 100% rebuild..

im just about sure its something injector related tho.

the engine would physically run fine, but boy it didnt sound like it was running right out the tail pipe..

[carrizog60]

mine has no issues at all...