If it ain't broke... don't do DP?!
 

Bought the car back in May - just trying to catch up on some regular maintenance. I bought the filter kit from DG online and so far I'v done the following to it:

1) Replaced air filter
2) Cleaned banjo bolt, pressure lines to and from the switchover valve and the valve itself (it needed it)
3) Adjusted the ALDA (3/4 turn CCW) because it was running like a snail off idle 4) Flushed the PS pump and changed the filter
5) Replaced GlowPlug #5

Here's my question: the filter kit shipped with the Diesel Purge kit - my question is SHOULD I do it if the car is running reasonably well (starts right, idles smoothly, no smoke and I get 30.3 mpg highway/city last check)? If it aint' broke don't fix it, right?!

On the other hand it may clean my IP, fuel lines etc. and do some good for the fuel delivery system....

Should I do it now or give it a rest?!

MF

Oh that DP. :eek: :D

Well, if I were to do anything, I would take the injectors out to be cleaned professionally. Actually, that is what I will be doing when time permits.

How much...
 

How much do you expect to pay for this service?! Just wondering...

Some say that Diesel Purge should only be used as a remedy such as when you have nailing or knocking instead of preventative maintainence. Personally, I'd go ahead and purge the system, if it doesn't help, it won't hurt.

Dont bother, it won't even make a difference.

Well, it is about $20 an injector to test, if they don't find anything wrong. I can take it out myself and have bought the parts.

Purge It?
 

IMHO, If you've got the stuff on hand I'd go ahead and do the diesel purge, then replace the fuel filters. I also replaced all of the rubber fuel lines at about that point. My car was a litle old lady car, that wasn't driven much in the last three years, so I had a fungus in the fuel problem. Wound up removing the tank and cleaning it out. It was amaizing the black crap that came out of the IP and back into the clear bottle. My wife said it made the car idle smoother. Nuff said.

Chuck.

purge
 

Diesel giant is a good guy and he would not be selling it if it did not work..
he has really helped me out...

I think the first step is to DP.... then the second step is to remove the injector and let it soak in a parts cleaner... (sever chemical) Then I think the 3rd step is to take them down and have the professional diesel injection service to calibrate and replace nozzels if needed. (this will cost half of a new set)

I'd say go for it. It might help in your case, not in mine because I had been running B100 for quite some time, which does as good a job of cleaning as the DP.

Had a non turbo 80 wagon, and I have a turbo 85 wagon now. Diesel purge has done nothing to help either one, and both seemed to nail afterward. (Lubromoly)
Just my experience.

If I had your engine doing 30+ miles per gallon in combined city/highway milage the last thing I would do is shake up the crud in the injection pump with a purge. I assume it is the 617 engine you are reffering to. It might truly be a case of if not broken break it. I have noticed the better pump rebuilders do not like this stuff and their explanation makes sense. You are simply probably getting the best fuel milage and performance this design is capable of right now. Others could duplicate it if they learnt to tune their engines with a system. They seem to like lower power than you have and poorer fuel milage as well. I want and seek all that is safely there myself. I do not suspect you have even one marginal injector but if you wanted to test for one it can or all of the injectors be tested in the engine quite easily at no cost other than a little time and a set of heat shields. That of course only is required if another simple preliminary test indicates the test is required. I guess the only thing I would think to recommend is to change out you fuel filter at factory specified intervals unless your area is noted for dirty fuel.

To me DP helped temporarily on the 300SD. In the end i replaced the injectors and all problems went away. I just got the part in and returned the car to my friend who bought it off of me, and the rebuilt injectors sure did make a big difference. It felt alot quicker then it did on the old injectors. I never really had a chance to drive it much when i installed the new injectors so it was nice noticing a big change in performance.

When my 87 300D had odd idle i used dp and it fixed it temporarily but this time i think ill probably go with bosio injector nozzles from kermaTDI.

I say if it has idle problems or anything at all funny run DP. If not you can run DP it wont hurt but you could save it for when you would really need it as a temp fix.

Mixed bag...
 

Well, I went ahead and did the DP last night then changed both filters at the end... the results are a mixed bag...

1) When I started the car this morning the idle was much smoother and the car was less 'clanky' when cold - something that was a small problem before...

2) The car runs much smoother at lower speeds (up to 40mph) - it accelerates smoother and it seems to shift smoother too - just initial impressions...

HOWEVER, the power seems to be lacking above 40mph - it seems that I've lost the nice boost starting at 2100 rpm I was used to feeling... at that rpm I'm used to feeling the turbo kick in and propell the car quickly to higher speeds - now it takes its time to get up to 60mph.

It acts like it did before I cleaned the ALDA lines - maybe the switchover valve is toast now, not sure. I plan on putting a boost gauge on it tonight to give it another check... not panicking yet (I hope)...

Also, when chaning the fuel filters I wasn't sure where to put the small rubber "O" ring - I put it in the only logical place on the threaded stem that holds the spin-on filter in place though I was surprised that there wasn't one already there...

personally, in about 20 years of driving diesels i only heard of dp when i started hanging around here about a year ago.

i havent tried it yet.

tom w

When I first got my 1980 240 TCane showed me how to do the Diesel Purge..
Afterwards we both felt that it ran smoother...

What I can't figure out is the thinking process of those of you who said it did not help your cars and it was thus a waste of time and money for others...

This is just like the situation with using Trans-X... which I have had dramatic success with on several old cars....

Both of these items are about $20 to try and I have seen no evidence that trying it without it being " needed" has done any harm.

If it does not cure your problem then a build up of varnish was not the problem with your vehicle... that is all either of these products claim to do.. dissolve some built up varnish in Very Small places where small build ups are a bad thing...

The fact that it did not seem to help your particular car means THAT WAS NOT THE PROBLEM WITH YOUR CAR... not that the ingrediants were proper or could not be effective if that had been the problem or that the concept of using a varnish remover was not legit.

The Philisophical concept here is " you can not prove the null hypothesis"...in case you want to look it up...