New Owner of a 1981 4door VW Rabbit Diesel**47.5MPG**Baseline

[bigchelis]

Hi all,
End of the Week and time to fill up the gas tank again. This time I am leaving about what appears to be a Quarter Tank left.

I drove exactly 326 Miles.
50% of those miles are stop and go traffic
30% 60MPH cruising
20% just city driving


6.32gallons of fuel used in 326 miles = 51.58 MPH

I really was hoping for 55~60

Oh well, I guess this is the way it goes. Make changes see the effects and keep ecomodding

[aerohead]

For the urban mix stirred into your driving soup I'd say that your 51+ is pretty sweet.
Steady speed highway driving is where the bigger numbers will come from.

[bigchelis]

Originally Posted by aerohead

For the urban mix stirred into your driving soup I'd say that your 51+ is pretty sweet.
Steady speed highway driving is where the bigger numbers will come from.

True and great point.

For my next 300miles I have deleted the cold air intake and gone conventional on that front. NO MORE COLD AIR just for kicks

• NO Cold Air
• Diesel KLEEN just poured into tank

[Cobb]

Has the oil and filter been changed recently?
Has the tranny fluid been changed?
How is the air filter?
Did you check timing belt condition and tension?
Is the cold start lever position to run when you posh the plunger in?
Are you using a tier 1 vs tier 3 rot gut diesel fuel?
Have you checked the parking brake tension?
Have you checked the rear wheel bearings?
Is the clutch petal adjusted properly?

Try going 55mph, but I bet the above wil leasily get you over 60mpg.

[bigchelis]

Please go easy on me; this is my first Diesel vehicle ever

Originally Posted by Cobb

Has the oil and filter been changed recently?
It looks new, so I left as is.
Has the tranny fluid been changed?
No idea, but it shifts like a dream. Perhaps synthetic tranny fluids would be a good upgrade.
How is the air filter?
It has a K&N Filter, so I Just purchased the Cleaning and Oil Kit and cleaned it.
Did you check timing belt condition and tension?
Belt and Tension look great.
Is the cold start lever position to run when you posh the plunger in?
I have No Idea what this means
Are you using a tier 1 vs tier 3 rot gut diesel fuel?
I have no idea what this means
Have you checked the parking brake tension?
The Parking brake is not installed. It is new in the trunk ready for me to install.
Have you checked the rear wheel bearings?
Didnt think of that, but I you got me worried now...
Is the clutch petal adjusted properly?
The clutch pedal has short travel. In fact, I could almost shift gears without a clutch. Not sure what this is indicative of

Try going 55mph, but I bet the above wil leasily get you over 60mpg.
Oh boy, I feel at 60MPH I am really pushing it. Perhaps as a last resort, but for now let the ecomods continue.

So, I have effectively cleaned the K&N Filter/ Put Kleen Diesel fluid in gas tank, and deleted the cold air mod to a more traditional one.




I will stick to these modifications for now. See what changes the next 300ish miles then continue on to other mods.


Thank you all,
bigC

[bigchelis]

The rear end portion of the exaust rattles when I grab it with my hand and shake it.

Also, upon start up my car rear makes a rattle sound which needless to say comes from the exausts muffler.


I can easily just chop the muffler off, and the tip of the exaust would be about where the rear tire begins. Not sure what this will cause. More diesel smell, more noise, ect....

[Cobb]

Diesels dont need mufflers and yes it rattles like a cans inside your exhaust.

Cold start looks like a choke knob from back in the day.



It in turns moves a never back and forth on the injector pump.



It changes the timing in 1 position and position 2 it ups the idle, position 3 its off.

If you use too much oil in the km filter it will work too well and trap too much trash. Try a warm air intake and a cold air intake.

Another thing to do is once you get it figured out try different driving techniques. If 3rd and 4th gear seems similar it would show you do not have over drive. Some 81s did and others do not.

If you have over drive there is a significant difference between 3rd and 4th gear and in many cases you need to shift back to 3rd to accelerate on even a mild grade or just maintain your current speed.

Lastly have you checked your valves? I know the mercedes diesels had 2 different settings for lashdepending on if you wanted more economy or more power.

Also try with the pcv connected if you have disconnected it. Although it can blow a lot of oil and foul the filter it does recirculate combustionable fumes back into the engine.

[bigchelis]

So if I cut that muffler or catconvertor it wil rattle no more? What about smell?

[Cobb]

Sorry bro, it will still smell and rattle with either cut off. ITS A DIESEL!!!!!

[bigchelis]

Originally Posted by Cobb

Sorry bro, it will still smell and rattle with either cut off. ITS A DIESEL!!!!!

What I mean is that right before the exausts tubing exits near the rear driver hatch area. It has a really big uggly round exausts. When I turn the car on it rattles like crazy, but about 2 min later it goes away.

I was just wondering these cars didnt come with cats so thats likely a cheapo muffler. Maybe a good 16in round replacement would do some good or for now just chop it off. Might sound better


My 4 speed stick shift is definitely the variant with a 4th being overdrive.
1~3rd gear all seem about the same then 4th is way tall gear.