new member, AAZ cold start and running problems help please

[bstro747]

hi there, new to the forum as ive just aquired a 1.9t aaz in a passat wagon
Great car but some problems with starting and running witch have become very noticable now the weather has started to cool off abit

is there a standard setting for the cold start as mine pulls out then pulls back in on its own?
the car starts, just and judders like thers a pallet of bricks in the engine and sounds like its doing some damage?
it idles at 1000 rpm and is juddering like this untill 1200/1300
have i got some timing isues as ive tried ajusting the idle turning it all the way down and all the way out until it screwed out the bottom? And nothing changed, there are 2 grub screws near the idle screw what do these do?
any help would be greatly apriciated,
Oh my name is ben and im in manchester
Thanks

[nathantheengineer]

Evening Ben,

Does the idle smooth out when the engine is up to temp or does it judder all the time at 1000 rpm?

It is not as cold now here as last week though!!

Nathan from Huddersfield

[bstro747]

Hi there, no its still juddering at 1000rpm its only smooths out and quiets down when driving, its a reel knoking noise, ive checked for air in the fuel, changed the oil ,oil filter and fuel filter if that ruels anything out,
it seems like thers not much power- not that ive owned a 1.9td befor but it seems realy sliggish, all noise no movement,

[nathantheengineer]

Did the previous owner have the timing belt changed?  A diesel is a remarkably simple idea, fuel and air at the correct time and she will run.

My aaz was sluggish before i turned the fuel and boost up but we need to sort your knocking issue before we get to that stage.

When starting what colour is the exhaust smoke??

[bstro747]

Its white what smoke is there, it only smokes when it boosts as i can see it out the back window if a car has its headlights behind me, have read about the fuels screw and wastegate adjustment and it seems someone has already had a tinker!! theyv marked a score line on the fuel screw and the tamper clip is of the lock nuts on the waste gate, will get to that stage once i get her running smooth ey! have just read about the two grub screws i mentiond


(On a AAZ the idle setting is on the back side of the IP, against the engine. There are 2 stop screws, one for hot idle and one for cold, and the cold start cable is attached to the idle pivot.
Since the cold start cable advances the timing and itīs connected by a rod to the idle pivot, does it also adjust timing when I set the idle speed?
With the fuel screw turned in a bit you have to unwind the hot idle stop screw pretty much to get the idle speed down so I would like to know if the timing is changed too?)

why do you ask about the colour of the smoke?
ben

[bstro747]

And yes the timing belt changed 22,000 ago

[burn_your_money]

Double check the crank to cam timing. It tends to wander and destroy engines...

[nathantheengineer]

It definitely sounds to me like the timing is off and would be the first thing i would check. 

However low compression would cause difficulty starting and also sluggish performance.

1, do a timing check,

2, do a compression check.

Hope that helps.

Nathan

[bstro747]

Ok been onto the previous owner and finaly got him to admit what hes been messing about with,
Hes moved the wastegate lock nuts towards the end
Adjusted the fuel screw but canot remember how much or which way
The two grub screws that i think are the hot and cold idle he has adjusted to get the idle down or something
So basicly im left with no stock settings by the sound of it,

it seems to me that the hot and cold screws could be somewere to start as it judders even when its warm 95degrees c, and this is at 1000rpm

Orderd a boost guage today so i can check whats going on with the turbo,

Which screw is the hot and which is the cold idle?
will post a picture up soon

and will check the timing and pressure asap

[theman53]

Faq section....how to make your 1.9td a faster car *or something close to that* there is also the 1.6 na a faster car and 1.6td a faster car, all of which could help you to learn about your pump. If he was messing with it there may have been problems that he was trying to fix. I would find out what those problems were if that is the case.

[bstro747]

[bstro747]

Do i adjust the cold start when cold an the hot when hot? cant realy find much that gives a description on how to do this,

[burn_your_money]

First you check the timing.  Search for "AAZ crank" and this will probably move up the priority list a bit. You are only checking cam/crank timing and it's basically as simple as removing the valve cover and turning the engine to TDC.

Ideally you would adjust the cold start with the engine cold, since that is really the only time that you will be using it. You don't adjust that rod in the picture, only the 2 adjusters that are locked with the 10mm nuts.

[bstro747]

Ok will check it out this werkend
 thanks for the help everyone

[nathantheengineer]

No problems, you will find this forum a font of diesel knowledge.

I hope that you find the cause straight away and that it is an easy fix.

Nathan