Get a load of this....

[speedball30]

As you all may be aware, I am having a tad bit of trouble with the fuel economy on my 97 Jetta 1.9 TD. I did a fuel flush and had it looked at by a fellow Board member who found nothing to be wrong and suggested I was driving it too hard, treating her like a gas car.
I took his advice and really paid attention to the turbo gauge and tried to keep it under 7 PSI at all times. Tried to not giver on green lites etc.
I still was only getting 480-500 Kms per 55 L. So I finally broke down and took it to the local dealership. Below is exactly what I was giving on my bill....$115.92 BTW.
1. Checked oil filter element - OK
2. Snow screen - OK
3. Put car on TDC at crank & ing pump - lines up dead on
4. Check pump stroke - 1.15 mm
5. Brakes are not dragging
6. Adjusted tire pressures
7. Tried to adjust idle lower but the adjuster screw is siezed
8. We do not have tester for pump or injectors
Can anyone enlighten me on whether or not I just paid $115.00 to have my tire pressure adjusted or did he actually check something of meaning?
All in all, only thing he found to be wrong was the tire pressure. He said that for every pound of pressure the tire was out, I was losing 2 MPG. He said thats probably why I am getting such poor fuel economy.
No I may be a complete moron when it comes to diesels but to me something sounds out to lunch here. Even if you were driving the car with the boost at 11 psi all day, I still think I'd get more than 480Km's to a tank...or am I right the f*&^ out of 'er???

[wyldman]

What type of driving are you doing ?

Has anyone check the cat ? I'd bet it's plugged up,which can contribute to poor mileage.

How does the car perform ?

[speedball30]

Car seems to run fine, it is a little more pokey in acceleration than I thought she would be. Usually you have to make her want to get to a speed. I do a lot of city driving but not in stop and go traffic.
Never thought about the cat, is it hard to check/clean?

[chrissev]

$115.92 BTW.
1. Checked oil filter element - OK

- I'm assuming they unscrewed the filter and looked inside?  Interesting.

2. Snow screen - OK

the one in front of the rad?  Why would they check that? Might make your car run hotter, but wouldn't do much for fuel economy.

3. Put car on TDC at crank & ing pump - lines up dead on

 if it didn't, you would have smoking and rough idle, which they might have noticed when they started the car.....then they wouldn't have had to do this check

4. Check pump stroke - 1.15 mm

this is useful.  they checked your pump timing for you.  That is worthwhile.  A good check, but a bit pricey for that.

5. Brakes are not dragging

push car back and forth, hmmm, no dragging brakes.  Either that or spin each wheel by hand while the car is off the ground.

6. Adjusted tire pressures

this one is funny.  Can't believe they did that.

7. Tried to adjust idle lower but the adjuster screw is siezed

and being a VW dealer they of course couldn't do anything about a seized screw.  Might not want to let them do your suspension...."tried to remove strut, but ball joint bolts were seized"

8. We do not have tester for pump or injectors

No they probably don't have that.  Interesting they never checked the air or oil filter, or the fuel flow, or the condition of the transmission fluid, or the most obvious cause of low fuel economy on a diesel vw, THE THERMOSTAT!  I would have thought that would be the first thing they would check.

[johnny]

Even if you put the motor to the limit you must get at least 750 km.

[BlackTieTD]

Can anyone enlighten me on whether or not I just paid $115.00 to have my tire pressure adjusted?

yes. after having worked at vw dealer for a year, generally the rule of thumb is, stay away from the dealer.

stick around here, these guys know their diesels and they'll fix you up.

[wyldman]

You'd have to do a backpressure test,to check and see if the cat is plugged.

It's easier to just remove or gut it.

[1985JettaTD]

personaly i dont think that driving the *** out of the car will have a huge hit on fuel consuption. i drive my 85 jetta w\ 1.6 turbo to the limits every day. 4000 rpm shift WOT at every light and 140 km\h on freeway. the car run great with about 850km a tank. the tranny has 550 000km and the motor has about 50 000km.

[BlackTieTD]

personaly i dont think that driving the *** out of the car will have a huge hit on fuel consuption. i drive my 85 jetta w\ 1.6 turbo to the limits every day. 4000 rpm shift WOT at every light and 140 km\h on freeway. the car run great with about 850km a tank.

sounds like how i drive mine. for some points of comparison, i get between 640-660km consistantly from a 45L tank. taking it easy on the highway i can get around 700-710km. worst is about 620km. 1982 rabbit 1.6L TD.

[HarryMann]

He said that for every pound of pressure the tire was out, I was losing 2 MPG.

Sounds incredibly pessimistic to me... so starting at 35 you drop to 25 and she's doing 20 mpg less...? Maybe for all 4 tyres, maybe not. Think this is an absolute worst case scenario being misquoted for everyone's professional benefit  :roll:

But you did take it to a VW dealer and commision the work.... whoever said thermostat, big Tick, and although diesels are less sensitive to pedal than petrols, it does make a difference as it has to! Keep accelerating a 1 ton mass faster than you need to, keep decelerating it 'cos you're going too fast - and if Mr Newton was still alive, he'd tell you THAT takes energy and energy is fuel!!! So back off a bit, read the road ahead, make early decisions and try to keep any monentum you do have - its called Advanced driving here, call it what you like over there, and it hinders everyone else less too... keep flowing and the rule is 'conservation of momentum', slower up hills and faster down the other side, constant energy driving, sacrifice kinetic for potential energy and vice versa. Over 65mph and the drag is going up out of all proportion to the reduction in journey time, our limits are 60 and 70 here, A road and M road respectively, about right, 80 mph and she drinks fuel - Fact!

PS. Have you checked your AIR filter is clean, its free to do so on a Sunday afternnon you know.............. one spanner?

[ricosuave]

yeah, something is off for sure

my 97 jetta idi, i get a minimum of 725km per tank

id check the fuel filter, the nozzles, the cat, the air filter and for any air leaks in the fuel system

rico

[speedball30]

To all that replied, thanks a bunch.
I was 99% sure the only thing they checked that made sense to me was the pump timing.
So I will start with replaceing the fuel filter and removing the cat to give her a look see. I will have to break down and send my injectors to SMOG to get new nozzles installed.
Thanks a bunch guys.

[hillfolk'r]

heres a funny,,if 1 psi tire pressure means 2mpg,,im going out to the garage rite now and putting 120psi in every tire,,,then im driving to california on 1 fill up,,ill get better mileage than the new lupo thanks for the tip!!!

[hillfolk'r]

:twisted: bang boom :?:  :!:  :!:  :?:  :oops: why did all 4 of my tires blow out??it was just sitting there,,120 psi and everything,,,,,those guys didnt tell you too much,,the rest of the guys here are on track,,let the dieselgods of vwdiesel.net guide your chariot to good mileage+power!!!

[tylernt]

:twisted: bang boom :?:  :!:  :!:  :?:  :oops: why did all 4 of my tires blow out??it was just sitting there,,120 psi and everything,,,,,

Actually, I used to run my rear tires at 40psi. Then I had the tread separate on a cheap tire from this "overpressure" condition. The tire went wumpwumpwump, had to replace it. Any money I saved on fuel went into a new tire.