engine runs great but poor mileage and smoking

[RabbitJockey]

when i first bought my n/a idi jetta it'd start like ***  even in nice weather, smoked like a *** as soon has the pedal was pushed in at all, and after a year of my love and money (it's almost as bad as a girlfriend)  anyway, after new injectors, stanadyne, and a replaced glow plug, cleaned out the evaporator(this made a bit of a difference, i guess because now the pump didn't have to work as hard).  it starts alright in the cold ( i run a gallon of kerosene and the proper amount of aviex for the cold starts)  and when my car first starts a cylinder misses (which i assume is a weak cylinder with a little bit of bad compression)  anyway  we had checked the timing of the pump, and my dads friend who is very adequate with vw diesel knowledge says the timing is set up above 1mm like 1.35 if memory serves me, but after cutting back the max fueling in order to stop smoking which made the smoking stop a little, but mostly just made my car even slower.  anyway, because of this he says that my pump is a rotten egg and that gettign the timing at it's proper location of 1mm or .9 or w/e as the book says will make no difference because the pump is a log.  currently my car only smokes under heavy acceleration, and it's more of a black haze that will cover the car behind me, but it's always very transparent and blows away quickly (unlike when i first bought it and it smoked all over the place with thick black clouds of doom)  anyway, everyone that's driven n/a diesel's before says my car runs great with lots of power compared to the other ones they drove, but it's still very slow.  the best mileage i ever got was 36mpg, the worrst was 28mpg currently my odometer is broken so i can't keep track of my mpg.  but i am very curious if my car needs to get the timing set proper if they will ease smoking, and make it start better...

[RabbitJockey]

also, i talked to the last 3 owners of my car, which goes back from the 182,000 miles it's at to about 140-150,000, and they all reported about 30-35mpg.    i think my 28mpg must have been one of the times i driving like a dick for an entire tank.

anyways thanks for any help

[RabbitJockey]

seems to run better with the cold start pulled out all the time...

[toomanycars]

If it runs better with the cold start pulled out then your timing is retarded. This would probably be accompanied by white smoke. If it misses when cranking the engine cold, suspect a glow plug. Take them out, give them 12v direct form a battery and they should glow red.

[wyldman]

Pump or belt timing is off.

[RabbitJockey]

wow, i never saw the responses till now.  but thanks alot!

[hillfolk'r]

yea man,we dont mess around :shock: (even though ididnt post),yes timing is slow,if it runs better when cold start pulled out,,make sure its pushed IN when setting timing,,it will mess you up!!

[RabbitJockey]

i dunno, it doesn't really seem better, i think that was more a speculation, it definetly runs different, but it seems like it's more grunty and torquey with the timing not advanced.  i'm doing a motor swap soon so i'm not too concerned with it anymore, but i still think i should get the timing set right.

but would it have these symptoms if the pump timing was set above 1mm, i think it was up around 1.35 or something.  don't remember well.  i know that's way over what it should be, but the guy that checked it told me that setting it correctly wouldn't make a difference.

[RabbitJockey]

but i also must note, that everyone that's ridden or driven my car says that it's the fastest n/a diesel they've ridden in.  even though it's still slow to normal car stadards.  and most of my friends are surprised by my 50 hp, it doesn't get anywhere near there mustangs, and isuzu rodeos, but it scoots for a diesel

[shwartzbewithyou]

If everyone say the power is fine then it most likely is.  However you're mileage still concerns me.  When mine was getting that bad it was because everything in the chain from the injector pump onward was leaking.  The injector lines, the injectors, the return lines.  I had more diesel evaporating off the front of the engine than burning in the engine (or so it seemed).  I ran a bottle of diesel injector cleaner through it and it cleaned it all right up (except for one but I've dealt with it since).  I figure it sucked up some crud from the bottom of the tank because it had been sitting for over a year when I bought it.  So when I ran the injector cleaner through it, it must've cleaned out the injectors and created less back pressure in the lines.  So everything stopped leaking.
So all that to say, any leaks?  Are your return lines clear? Can you see in them to see how much is being sent back to the tank?