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2008 PT, 1998 neon--1965 VW 1200
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Discussion Starter #1
I have a few questions about the diesel injection system.

when the car is cold it "knocks" until it is warmed up, atleast on the first notch(100 degrees) of the gauge.

is this knocking the nailing i have read about before? i thought the engine was just old, but if its just a fuel injector problem, ill get at it and get rid of it, i cant do anything internal, but injectors come off easily=)

i ran some sea-foam cleaner through it that my dad got for me and it seems to start a little easier and now i want more! i want the durned thing to turn at the first peck of the starter motor! not 3 cranks!

i was reading(as always...) and i came across something over at shopforum and it said the injector is only 5 parts(?) and generally only needs to be cleaned with laquer thinner(which i have in abundance) a brass brush and a toothpick.

the main questions are as follows:
i cannot find diesel purge locally and want to clean the fuel system as best i can(ive done the filters and tank/tank screen (pictures soon. maybe along with some injector pictures)

would i be better served to spend the 20 bux to have the purge delivered?

will this cleaning procedure produce the same(or better) result?

and finally--

will i futz around and lose an errant spring with a bad attitude thatll go shooting off into some dark corner of the garage, or even worse...way off into the camelllia in the yard? (ohh that camellia...the metal things always travel to it, as if it were magnetized! once it dented my car.. but i digress..)

so what say youall?
 

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Get a junk injector from a shop or a junkyard, offer $5. Read the factory shop manual for instructions. Take it apart and clean it as a learning exercise. Ask more questions and then decide to clean the ones on your car.
 

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You can clean them yourself, but how will you adjust the 1) opening pressure 2) holding pressure 3) spray pattern?
If you want results, as in professional results, then you should take your injectors to a diesel injection shop and have them tested for the three criteria I outlined above. Otherwise you can clean them yourself but you had better be sure you know what you're doing. They require precision equipment to rebuild them correctly. When you go to put them back in they'll probably nail just as bad or worse if they are not rebuilt by a pro. If you just want to clean them run about 5 or 6 bottles of purge through the system, and I mean take a nice drive on the purge, and put your foot in it. Less risk of leaks that way, and less work. You can buy new ones, but your old ones are probably better if they are original as they were made in Germany, not India where they're made now. Indian nozzles are way inferior. Just have your old ones rebuilt if you can.
Next, you could check your injection pump timing. Get a ohmmeter and check your glow plug resistance. Should be less than 1 ohm- if more, replace the plug. You see, the glow plug's job is to heat the combustion chamber enough so the fuel/air mixture will ignite at startup. If one or more are bad you'll have that knocking or nailing sound until the car warms up. Check the relay too.
After that, valve adjustment time. Makes a huge difference. Check your timing chain for stretch while you're at it as this affects the injection pump timing. And finally, make sure you have a real potent battery. It's hard to beat a Die-Hard International Group 49 with 1000CCA especially made for this vehicle.
If you do these things and it doesn't make a difference, you have low compression and you can't do anything about it save for new valve guides and seals, new valves, replacing the piston rings, tearing down the engine and resleeving the block, or replacing the engine with one with lower miles. I could live with a lot of startup knock before I'd go that far.
 

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2008 PT, 1998 neon--1965 VW 1200
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Discussion Starter #4
yeah, its not THAT bad

i just want to make sure its running as close to 100% as i can! the car was purchased in january as a trade in on a new ford vehicle, the second dealer(that bought it from ford) only had the car for 3 days until i snapped it up!

he didnt do anything to it and still prolly cleared a grand. i bet the ford people were upside down even trying to service the car, its no taurus, thats for sure!

after a few coats of wax and lots of elbow grease, ive gotten it into what i see as decent running shape and could easily sell it for a profit(right under 130k miles) ive just been running lots of power service white and i ran a can of sea foam through it as well and that seemed to level it out well, but ive fealt improvement... now i want more!

my goal is to use all 65 horses! right now i feel like its about 55=) when i got it...around 35. tank screen was so plugged the car would only run when the tank was so full gravity would feed the fuel through and when it got low it would cut off.

a caliper sticking about 1/2 inch out isnt helping, but i dont think its dragging.

now i hear a thump when i turn a corner and hit a bump. maybe ill post that now and see about doing it this weekend!
 

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There is only one adjustment - pop pressure. The adjustment doesn't change from cleaning the injector. It is adjusted by changing spacers, you put the same spacer back in, you have the same adjustment. Once you look at the insides of one and read the manual you will never waste another dime on Seafoam or diesel purge or any such chemicals.

Read the book. Bad advice is everywhere, read the book.
 

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Just because I gave a more thorough and comprehensive explanation, I give bad advice? What?
iNeon
There ARE 3 separate means of adjustment 1)opening pressure('pop' pressure in pajamas' layman terminology) which is done with SHIMS 2)holding pressure which is done by REPLACING THE SPRING as sometimes it WEARS OUT which is COMPLETELY UNDERSTANDABLE after TWENTY YEARS 3)spray pattern is done by CLEANING the NOZZLE or REPLACING IT. Diesel Purge is a legitimate way to clean your fuel system, regardless of what ignorants have to say about it. It won't work as well as injector rebuild will for cleaning the injectors if they have not been kept clean over the years, but the alternative is much more involved. Many many people report good results using the purge. If you want top performance, go through all of the relatively easy procedures I outlined in my earlier post. Also, do read the FSM(the 'book' as pajamas so eloquently put it). Won't tell you much different.

pajamas
Learn what the hell it is you are talking about. At least you are correct on the bad advice, however it is a bit of a self-indictment which is stupidity on your part. I'm surprised people like you live beyond their 12th birthday without Darwin's theory taking you out of the picture.
 

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I call replacing nozzles and springs replacing parts, some would call it rebuilding an injector. Do you call dropping in a shortblock adjusting your engine?

The spacer is the only adjustment. Spacers are available in different thicknesses for this purpose.

You funny. Calling names, wow. Take a look at the man in the mirror. Abuse of personal freedom by a few jeopardize personal freedom for all. Stick to the facts, leave off the personal attacks.

Once again, clean an injector once correctly and you will never waste money on snake oil products again.

Read the book about the pintle and the tiny holes in the pintle. Look at the holes with a magnifier. You will see why diesel purge and seafoam cannot possibly clean those holes. If you still don't believe it soak a clogged pintle in one of those chemicals and you can see that it will not clean those holes. They may work if you dig at the blockage as described in the manual. Use brass to clean, not steel.

This is not difficult, anyone with a diesel should know how to do this. But then again, anyone with a brain should be able to express their thoughts without name calling.
 

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'Calling names, wow.'

Can you read? If so, then please point out where I called you a name. I just basically said you were stupid, because you are. 3 adjustments pajamaboy, 3. Not 1; three.

BTW- as soon as you install a new injector and run the car it will get black coking around the nozzle. Does that mean it's gone bad? No. A clean enough nozzle will still look dirty as hell.
As I said before Pajama pants interjected if you want to use purge then use it. It will make a difference, but not the huge one you may be expecting. It's cheap and easy though, we can't all go out and pull our injectors which is what Mr. PJs can't seem to understand. He doesn't understand that 1)new injectors require new heat shields 2)new injectors require new return hoses 3)new injectors require torquing the injectors to proper factory specs 4)not everybody is equipped for that 5)diesel purge works in a pinch and that's a fact of life
 

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Discussion Starter #9
simmadownah!

boys boys boys--

i just wanted to clean them the most thorough way possible! i dont have the money to pay someone 100 bux an hour to learn how to work on my car. i dont have the money to throw parts at a problem and i dont have the money to pay someone to fix my headache after ive torn the thing apart and it was harder than someone on the internet told me it would be.

it isnt a big deal. it is only on cold starts and for about a minute id say. it isnt even bad, its just not "right."

i'll just wait for my summer loan and then take it to a mechanic.

thanks for the replies
 

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Read the book, ignore the hysteria.

I bought the pop tester myself. You might not want to invest the money. It was worth it for me. You can buy one for about $150. You don't have to have it.

This ain't rocket science. Cleaning your injectors on a 617 diesel is about as difficult as cleaning the spark plugs on an antique chevy pickup truck.
 

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W-1-2-3 Go!
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I just purged my diesel and she now purrs better! Here's a very good analogy I came up with.

Think of your last meal. Imagine it was fried chicken with all the grease. You gobble it up and now you feel full, right? Then you start to have difficulty breathing. That's how it felt before. Well, the purge is like having all that food in your tummy digested in your intestines and you can now move about and breathe easily! It did feel smoother both at idle and at speed. That's exactly how it felt when I test drove it around the block, with a friend who helped me, and I kept the original pre-filter. It was dirty! I think I saw sand-like particles inside it! [:0]

Also changed filters and primed/pumped it. Started on the first crank, and kept it idle for minutes to check if any air got through. None. Good. Drove with my sunroof half open, windows down, and Metallica's Enter Sandman blasting through my stock speakers...

I have yet to check the sound of the injectors if it made any difference...

iNeon, maybe that's all your car needs? It will be worth the $20 shipping cost, I tell you! I haven't even used up all of it!
 

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Discussion Starter #12
i guess it couldnt hurt, i found the stuff for 7 dollars somewhere, thats only 3 1/4 gallons of fuel...

100 miles of travel or a purge? =)

enter sandman?!? good lord child, get some Tori Amos up in there! i dont mean the new happy mommie Tori either, she used to be pretty angry, the Sugarcubes are also fun for a laugh...those zany icelanders.

the people passing you will wonder why youre having so much fun driving and give you crazy looks, but it isnt all that bad..atleast you arent bumping fiddycent rolling on dubs in a 1982 caprice with candied paint and a gold grille=)
 

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Lol!! Yeah, I just don't mind them. Hey I found that Diesel Purge on Performance Products and Mercedes Source (both dot coms).

I enjoyed my music so much I think I was the one who passed them [:O] but didn't go over 50 [:D]

When you get those cans of DP, buy them in bulk so your 100 miles or $20 or more will be worth it! I'll PM you how to do it easier when you get them. Goodluck! I do hope that's all your car needs (like a cough syrup [:D])

iNeon - 4/18/2005 12:43 AM

i guess it couldnt hurt, i found the stuff for 7 dollars somewhere, thats only 3 1/4 gallons of fuel...

100 miles of travel or a purge? =)

enter sandman?!? good lord child, get some Tori Amos up in there! i dont mean the new happy mommie Tori either, she used to be pretty angry, the Sugarcubes are also fun for a laugh...those zany icelanders.

the people passing you will wonder why youre having so much fun driving and give you crazy looks, but it isnt all that bad..atleast you arent bumping fiddycent rolling on dubs in a 1982 caprice with candied paint and a gold grille=)
 

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Hey ineon, watch it! i got a '78 caprice. It isnt on dubs or have a gold grill, its 100% stock so nothing to worry bout. but thats just my project car, doing a timing chain on it actually right now. My 82 300d turbo is the real deal![|)]
 

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Buy the pop tester and sell it later on eBay. It doesn't cost you much that way and you can deal with injectors without resorting to blind faith or voodoo.

You can read the manual online if you don't have it or want to buy it.
 

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'...blind faith or voodoo'

Dude are you completely illiterate? He doesn't have the money for that stupid pop tester which nobody needs unless they rebuild injectors for profit! Who the hell would actually go to the trouble of getting that thing, paying for it, and eBaying it afterward just to clean the fuel system out in an already decent running car? Let me guess...you would! Condolences- the bums lost!

I say diesel purge it, and test your glow plugs with an ohmmeter(borrow one from somebody). The purge will make it run smoother, but I think the real problem lies in a glow plug or two that happens to have more than 1 ohm resistance.
 

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doofwop - 4/20/2005 5:11 PM

'...blind faith or voodoo'

Dude are you completely illiterate? He doesn't have the money for that stupid pop tester which nobody needs unless they rebuild injectors for profit! Who the hell would actually go to the trouble of getting that thing, paying for it, and eBaying it afterward just to clean the fuel system out in an already decent running car? Let me guess...you would! Condolences- the bums lost!
I am starting to understand why your mama named you doof.[:D]
 
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