Your water injection system is set up as a performance system. It only comes on at full throttle/high boost to cool the combustion chamber and lower EGT.

See if you can get it set up so you can turn it on when cruising on the freeway. Maybe a push button or momentary switch.

I would try using it at legal freeway speeds. Down shift so the rpms are between 2500 and 3000. Turn on the system. If the engine falters after a while, then it is injecting too much volume for continuous use. In that case you will have to control the volume by turning it on and off.
This water therapy will help clean the cylinders and may help loosen stuck rings. It will not help if the problem is warn off metal.

Do this at your own risk. YMMV

__________________
Greg
2012 S350 BlueTEC 4Matic
2007 ML 320 CDI
2007 Leisure Travel Serenity
2006 Sprinter 432k
2005 E320 CDI
1998 SLK230 (teal)
1998 SLK230 (silver)
1996 E300D 99k, 30k on WVO
Previous:
1983 240D, on WVO
1982 300D, on WVO
1983 300CD, on WVO
1986 300SDL 237k, 25k on WVO (Deerslayer)
1991 350SDL 249k, 56k on WVO - Retired to a car spa in Phoenix
1983 380 SEC w/603 diesel, 8k on WVO
1996 E300D 351k, 177k on WVO

__________________
'80 300SD - '83 240D - '00 E55 AMG - '02 G500

Have you used this? Does it work?

__________________
"Senior Luna, your sense of humor is still loco... but we love it, anyway." -rickymay ____ "Your sense of humor is still loco... " -MBeige ____ "Señor Luna, your sense of humor is quite järjetön" -Delibes

1982 300SD -- 211k, Texas car, tranny issues ____ 1979 240D 4-speed 234k -- turbo and tuned IP, third world taxi hot rod

2 Samuel 12:13: "David said to Nathan, “I have sinned against the Lord.” And Nathan said to David, “The Lord also has put away your sin; you shall not die."

Kent at MercSource swears by it for his MB diesels. I use it in my OM617.

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'80 300SD - '83 240D - '00 E55 AMG - '02 G500

I was just momentarily at 120.

I have been hesitant to try manual control of injection system I will work in that it does have an on off switch

The real problem is I have $2000 in my car fund and I owe $4500 on this Mercedes and I am a food and luggage deliver driver for a job It is the catch 22. I can not get rid of this car and can not save money to get another car because I am spending money on this car and I am out of credit line.

I am wondering if the problem with my grease system was one of the valves was letting veg in more than I thought Before it finally stopped working right because it was perfect for 4 years on grease

Yes, if you are running a 2 tank system, it is possible that your purge valve was allowing too much grease to return to the petro diesel tank.

Congrats, 4 years on grease in a CDI must be a record at this point it time. You probably got that far because you drive every day and refill the tank frequently.

The problems you are now having most likely are due to sticky polymers starting to clog your HPOP, fuel rail, injectors, valves, rings, etc... also there are coking and corrosion deposits on and in the injector tips, valves, and the top compression rings on the pistons. It is my belief that your car is pretty much finished at this point. The money saved on fuel has to be weighed against the cost of replacing the car. If you get a cheap W123 next time, then you can drive more carefree.

I figure I have saved $15000 in fuel over the last four year just on this car. I am ahead of anything this nice and it still work. And it still works good. I spent $600 last month on fuel and oil think what I would have spent at $4 instead of $2. Last month was a busy month. Maybe not so much this month.

It is still a great car. I will tell you if it gets better( doubt it) or worse and how soon.

How did you save $15k in fuel driving 80 k miles? What kind of fuel economy were you getting and how much $ a gallon avg were you using in the calculation?

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85 300D turbo pristine w 157k when purchased 167,870 July 2025
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

Good questions. Perhaps the odometer got greasy?

The OP's statement would be supported assuming fuel economy was 20 mpg (frequent prolonged idling) and fuel prices averaged $3.75 per gallon.

Here in Albuquerque diesel is now $1.68/gal

I had very good luck with Kreen. Used it on my 96 E300 with almost 300k miles and it cleaned out stuck ring and other junk inside.

__________________
06 MB E320 CDI 123k miles
14 Sienna (wife's DD) 36k miles
11 GL350 Bluetec 136k (Sold)
96 E300; 292k+ miles (Donated)
11 Sprinter 22K+ miles (Sold)

Wait - you were using a grease system on a CDI?

"Well there's your problem"

http://youtu.be/LxhF7iBueeE

But seriously check out this document from MB

https://www.mbusa.com/vcm/MB/DigitalAssets/pdfmb/serviceandparts/biodiesel_Brochure5.pdf

This is written for the "modern" engines but most of this applies to the 648.

__________________
The OM 642/722.9 powered family
Still going strong
2014 ML350 Bluetec (wife's DD)
2013 E350 Bluetec (my DD)

both my kids cars went to junkyard in 2023
2008 ML320 CDI (Older son’s DD) fatal transmission failure, water soaked/fried rear SAM, numerous other issues, just too far gone to save (165k miles)
2008 E320 Bluetec (Younger son's DD) injector failed open and diluted oil with diesel, spun main bearings (240k miles)

1998 E300DT sold to TimFreeh
1987 300TD sold to vstech

Awesome link. Thanks for sharing!

If you want to use VO of any kind, stick with the older IDI engines (last of which was the OM606 in the 1999 E300, in USA anyway). Even on those you can still get some of the same problems. VO is best used in a disposable (cheap) car, or at least disposable engine.

Biodiesel is very, very, different than straight vegetable oil. Completely different. I don't know how much stronger I can state that they are not the same or even close.

__________________
Greg
2012 S350 BlueTEC 4Matic
2007 ML 320 CDI
2007 Leisure Travel Serenity
2006 Sprinter 432k
2005 E320 CDI
1998 SLK230 (teal)
1998 SLK230 (silver)
1996 E300D 99k, 30k on WVO
Previous:
1983 240D, on WVO
1982 300D, on WVO
1983 300CD, on WVO
1986 300SDL 237k, 25k on WVO (Deerslayer)
1991 350SDL 249k, 56k on WVO - Retired to a car spa in Phoenix
1983 380 SEC w/603 diesel, 8k on WVO
1996 E300D 351k, 177k on WVO

Yes, that is correct. The MB brochure linked above explained it very well.