Diesel purge, potential issues?

halfbytecode · Oct 7, 2017

Hi,

My car has a 1.6 TDI CLNA engine, that is almost 7 years old, and has done over 124,000 kms. The fuel quality around here is not good. The fuel filter is replaced every 15,000 kms!

Anyhow, the injectors on this engine are prone to failure around here. Fortunately, I have not had any injector failures.

Considering diesel purge does not clean injectors entirely, is it likely the injectors could get clogged from the movement of any deposits in them, or lead to another issue with the car?

Am I better off not performing the diesel purge, considering the otherwise failure prone injectors?

Henrick · Oct 8, 2017

Firstly, where is that 'Somewhere' location? Looks like you have a Polo Sedan - is this in Russia?

Do NOT change fuel that often! New fuel filter lets in larger contamination particles than slightly clogged one. Let the fuel filter run 40-45k km before changing it. You are really doing more harm than good with that.

About 6 months ago I performed injector cleaning procedure on my 1.6 TDI. I bought 2 cans of Liqui Moly Diesel Spulung. I installed an in-line clear fuel filter on the return line. Ran the fuel tank nearly empty. Added entire can of LM to the tank. Ran it nearly empty again. Noticeable power loss due to the purge. Then again added one more can, ran it till nearly empty. Added 1 liter of diesel to the tank. Ran it till nearly empty. Then I visited the gas station and filled in the tank with premium diesel. Went to my garage and removed the in-line fuel fulter which remained clear (no color change, no contaminants, etc).

When I say 'ran it till nearly empty', I mean I was driving the car at various speeds and various RPMs, not idling!

Upon next few tanks I noticed slight mileage improvement (or is this my imagination only??).
Also, Seems that LM freed up the DPF - I have seen the longest distance between the regens ever right after the cleaning procedure.

halfbytecode · Oct 8, 2017

Henrick said:
Firstly, where is that 'Somewhere' location? Looks like you have a Polo Sedan - is this in Russia?

Do NOT change fuel that often! New fuel filter lets in larger contamination particles than slightly clogged one. Let the fuel filter run 40-45k km before changing it. You are really doing more harm than good with that.

About 6 months ago I performed injector cleaning procedure on my 1.6 TDI. I bought 2 cans of Liqui Moly Diesel Spulung. I installed an in-line clear fuel filter on the return line. Ran the fuel tank nearly empty. Added entire can of LM to the tank. Ran it nearly empty again. Noticeable power loss due to the purge. Then again added one more can, ran it till nearly empty. Added 1 liter of diesel to the tank. Ran it till nearly empty. Then I visited the gas station and filled in the tank with premium diesel. Went to my garage and removed the in-line fuel fulter which remained clear (no color change, no contaminants, etc).

When I say 'ran it till nearly empty', I mean I was driving the car at various speeds and various RPMs, not idling!

Upon next few tanks I noticed slight mileage improvement (or is this my imagination only??).
Also, Seems that LM freed up the DPF - I have seen the longest distance between the regens ever right after the cleaning procedure.

Well, it is a high dust area (as per VW), and the fuel quality is also bad.

Actually, VW recommends changing the fuel filter (and all other filters too) every 15,000 kms around here. It is there in the maintenance information.

I was thinking of running the Liquid Moly Diesel Purge directly, without putting it in the fuel tank, as described here: http://forums.tdiclub.com/showthread.php?t=87948

What do you think about running diesel purge through these otherwise failure prone injectors?

This is the first time I am reading about the drop in power. Is it restored now?

Kalter|Tod · Oct 8, 2017

diesel purge will not hurt the injectors..... not one bit.... I have used it on countless vehicles and it has never harmed a thing..... I do recommend running it directly through the ip just make sure that you put an inline filter on the suction line so it does not suck up any of the free particulate matter that gets flushed out of the injectors......

Drive more worry less.

halfbytecode · Oct 8, 2017

Kalter|Tod said:
diesel purge will not hurt the injectors..... not one bit.... I have used it on countless vehicles and it has never harmed a thing..... I do recommend running it directly through the ip just make sure that you put an inline filter on the suction line so it does not suck up any of the free particulate matter that gets flushed out of the injectors......

Drive more worry less.

Thanks. I have seen some videos that show the inline fuel filter on the return line to the diesel purge container.

Would it be better that way, if I plan to put the leftover diesel purge into the fuel tank?

vanbcguy · Oct 8, 2017

There shouldn't really be any diesel purge left over. It's definitely safe to dump in the tank though.

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turbobrick240 · Oct 8, 2017

So where is VW recommending 15k km fuel filter changes? We won't laugh, really. Do the old filters look dirty when changed? I'd think there would be more risk of dust/contamination getting in from cracking the canister open so often.

halfbytecode · Oct 9, 2017

vanbcguy said:
There shouldn't really be any diesel purge left over. It's definitely safe to dump in the tank though.

Sent from my LG-H873 using Tapatalk

Yes, I was thinking of pouring the little amount left in the container, when the engine is switched off timely, so as to prevent running without any fuel or diesel purge intake.

I think it would be better to place the inline filter on the return line to the container for that, to ensure diesel purge remains clean(er) and deposits are filtered away.

turbobrick240 said:
So where is VW recommending 15k km fuel filter changes? We won't laugh, really. Do the old filters look dirty when changed? I'd think there would be more risk of dust/contamination getting in from cracking the canister open so often.

From what you said, I think we have different kind of fuel filters here. They are sealed units, and there is no canister to open.

The sealed unit is taken out, a new sealed unit is put in its place, and the fuel lines are hooked to it.

VW really seem to have thought this well, as they have eliminated the possibility of dust or other contaminants from getting into the fuel filter/canister, by making sealed fuel filter units.

halfbytecode · Oct 11, 2017

I just did this successfully. There is a perceivable difference, but I feel there is still more to "purge".

I used 500 ml of diesel purge. Should I do it again with another 500 ml of it right away, or should I leave it as is?

BobnOH · Oct 11, 2017

Maybe try using a fuel additive appropriate to your conditions.

vanbcguy · Oct 11, 2017

If your primary objective is cleaning the pump, the best thing to do is to start it up running off the diesel purge, let it run till the purge is at least 3/4 gone, then shut the engine off and let it soak overnight. That'll give it plenty of time to do its job. By the time you're that far down the bottle there shouldn't be much besides purge in the pump.

I just realized I'm not sure what sort of injection system you have - is it a VE pump or is it more like a PD?

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Henrick · Oct 12, 2017

His is CR. I doubt there's anything inside the pump what you might want to clean up and soak overnight

billiebbyy · Nov 12, 2019

I’m looking to do the same thing on a PD engine. Should I run it through and let it sit or...?

Mongler98 · Nov 12, 2019

just do like Post 11 says. its probably not going to do anything from "soaking" but its not going to hurt anything either.

Diesel purge, potential issues?

halfbytecode

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Henrick

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halfbytecode

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Kalter|Tod

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halfbytecode

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vanbcguy

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turbobrick240

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halfbytecode

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halfbytecode

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BobnOH

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vanbcguy

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Henrick

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billiebbyy

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