Easy Lubro Moly Diesel Purge How-To - with pics!!

sickagain

Member
Joined
Jul 23, 2014
Location
Portland, OR
TDI
2003 Jetta TDI Wagon (manual conversion)
Did this today, also changed the fuel filter. I did it a bit differently though, I didn't buy the fuel filter and vacuum fittings. Instead, for roughly the same price, I bought a second bottle of diesel purge and used that as a temporary fuel tank like so (after dumping the first bottle in the filter) :




image from http://flickr.com


Basically I filled the filter with diesel purge, disconnected the lines to the tank, attached tubing to those connections on the filter and ran them into a second bottle of diesel purge so it would be full strength (at least until that second bottle got sucked dry). Then hooked everything back up and drove it hard with the remaining diesel purge still in the filter.
Car runs much better, but honestly I think it was the filter (possibly long overdue). It ran smoothly before but now has more power.
 
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sdean7855

Veteran Member
Joined
May 17, 2006
Location
Kingston, NY
TDI
2003 Jetta
But isn't the filter in backwards? Or is it on purpose?

My inline filter shows a flow direction such that the incoming flow encounters the outside of the enclosed filter media, where you can see any crud and where there is more room for it. This setup has the direction reversed.
Or have you done this on purpose because you expect any crud showing up to come after it's gone back to the bottle and and when it goes back again?
 

jlav0330

Veteran Member
Joined
Jan 5, 2020
Location
SoCal
TDI
2003 Golf
It is possible to do this with just pouring the diesel purge directly into the new fuel filter, and then leaving the engine to idle for 10-20 minutes?
 

IndigoBlueWagon

TDIClub Enthusiast, Principal IDParts, Vendor , w/
Joined
Aug 16, 2004
Location
South of Boston
TDI
'97 Passat, '99.5 Golf, '02 Jetta Wagon, '15 GSW
When I change fuel filters in my rotary pump cars I prefill the filter with diesel purge. Although it does get diluted, it also gives the pump and injectors a shot of cleaner before that happens. I also try to do it with the fuel tank as low as possible. Although not as good as running the car directly on it for the entire can, it does help.
 

BobnOH

not-a-mechanic
Joined
May 29, 2004
Location
central Ohio
TDI
New Beetle 2003 manual
That's just good practice, I do the same. But to get the full benefit from Diesel Purge you must run it straight, allowing the unused portion to return to the container.
 

BobnOH

not-a-mechanic
Joined
May 29, 2004
Location
central Ohio
TDI
New Beetle 2003 manual
And just to post more, if you fill that filter every 20k with DP it's unlikely you'll every need the DP service. If you have a really old or neglected vehicle it could help.
 

jlav0330

Veteran Member
Joined
Jan 5, 2020
Location
SoCal
TDI
2003 Golf
And just to post more, if you fill that filter every 20k with DP it's unlikely you'll every need the DP service. If you have a really old or neglected vehicle it could help.
Just bought the car beginning of the year, 194k and not only do I not think the previous owner never did the diesel purge, I don't think the fuel filter's been changed for a while. Never mentioned it. He did, however, keep good care of the car and wrote down everything he did. Original owner too.
 

wonneber

Top Post Dawg
Joined
Oct 12, 2011
Location
Monroe, NY, USA
TDI
2014 Jetta Sportwagon,2003 Jetta 261K Sold but not forgotten
Just bought the car beginning of the year, 194k and not only do I not think the previous owner never did the diesel purge, I don't think the fuel filter's been changed for a while. Never mentioned it. He did, however, keep good care of the car and wrote down everything he did. Original owner too.
Did you get the timing belt history?
VERY important.
If it's not mentioned I would assume it never was and do it immediately!

If all the rollers, tensioner, and water pump are not documented those are likely to cause the belt to jump.
 

jlav0330

Veteran Member
Joined
Jan 5, 2020
Location
SoCal
TDI
2003 Golf
Did you get the timing belt history?
VERY important.
If it's not mentioned I would assume it never was and do it immediately!
If all the rollers, tensioner, and water pump are not documented those are likely to cause the belt to jump.
Yes it was all done at 150k, I'll make sure to have it done at 210k, y'all scare me with the horror stories of when this breaks (aka RIP TDI).
 

BobnOH

not-a-mechanic
Joined
May 29, 2004
Location
central Ohio
TDI
New Beetle 2003 manual
Yes, many cars have interference engines, bad news if belt fails. Plus on our TDIs we see a lot of previous jobs done partially or incorrectly.
 

tregowner

New member
Joined
Aug 13, 2024
Location
Toronto
TDI
Touareg
Hello everyone. I want to do the purge on my 2010 Touareg V6 TDi. I get the jist of making a direct purge, but i am wondering, on the return, diesel fuel thats already in HPFP gonna return to the mason jar and dilute LM DP, or are the amounts that will be returned are negligible?

Also i have codes poping up for cylinder contribution/balance. Would purging help address it or is there a high chance i may have to replace them?
 

OlyTDI

Veteran Member
Joined
Dec 18, 2007
Location
Olympia, WA
TDI
'04 Golf
Can't help with the second question but with regard to the first, the return will only dump a few feet of length's worth of fuel into the jar. Probably like a quarter cup. After that, it's all DP albeit with a quarter cup of diesel added. Yes -- negligible.

I just did my Golf tonight and swapped out my CAT 2 micron filter while at it. The Cat had 60K miles on it and it looked nearly new!
 
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