problems with my 1.6 N/A, has anyone heard of this b4? i havent

[oldskool rich]

i was driving along last week, engine running fine, then all of a sudden i went down to 3 cylinders
popped the bonnet and an injection pipe has snapped on number 2, so i replaced it but engine didnt sound so gud after that, it was pinking and running lumpy at a certain rev band
300 miles later, the same happend agian snapped number 2 injection pipe, and then again 200 miles later, it still pinks badly at low revs but sounds ok at high revs, i did the timing with a depth gauge, and i changed the injector so problem is either in or around the injection pump

any ideas?

[VWSmokr]

Yeah, I've broken a couple of them. Rumor says it's because I hadn't replaced those little rubber vibration isolators between the lines at the clamps after they fell off. Could be true; IDK. YMMV

J.R.
SoCal

[burn_your_money]

Did you securely tighten down all 4 pump mounting bolts? Did you loosen off and retighten all of the injection lines?

[zozie]

VW mechanic friend of mine said the same about tightening the pump and the high pressure line on the pump. He says if they go just even a little loose, the vibration will snap them

[Rabbit on Roids]

Yeah, I've broken a couple of them. Rumor says it's because I hadn't replaced those little rubber vibration isolators between the lines at the clamps after they fell off. Could be true; IDK. YMMV

J.R.
SoCal

i havent had the rubber vibe isolators on either of my diesels for quite a while.

[Rabbit on Roids]

how would i get an engine fire? all the hot *** is on the other side of the engine. besides, who cares if i do, i carry fire extinguishers with me at all times, its not gonna get out of hand.

[idgtd]

I know I'm wasting my time, but here goes.....

how would i get an engine fire? all the hot *** is on the other side of the engine.

Well, fuel is flammable. And I know you're thinking "diesel fuel doesn't burn too well, it will put out a match, etc." but many times when the injection lines break they form a hairline crack, which atomizes the fuel all over the engine compartment very well. And atomized diesel will ignite quite readily. I agree it's a small chance, but given consequences, why risk it?

besides, who cares if i do, i carry fire extinguishers with me at all times, its not gonna get out of hand.

And this tells me that you've probably never put out a well fed fuel fire on a vehicle with a fire extinguisher. If the fuel is flowing (electric lift pump incorrectly added and still running, engine running, residual pressure in pump, etc.) and it's burning, you have very little chance of putting the fire out before serious damage occurs to the vehicle. I've worked a racetrack a good bit, and I've seen construction equipment burn down from fuel line splits, despite the driver/operators efforts with a fire extinguisher.

[fdnyguy]

how would i get an engine fire? all the hot *** is on the other side of the engine. besides, who cares if i do, i carry fire extinguishers with me at all times, its not gonna get out of hand.

Famous last words......

Be careful out there....







Stay safe, stay well. Jimmy.

[Rabbit on Roids]

im not some random dumbass thats going to leave my car running while its burning down. thats stupid. shut off all power when you think something is wrong. right? right... anyway, how is my IP or lift pump going to pump fuel after the engine is shut off? i would notice a broken line, because i would have a dead cylinder. i would put the stupid vibe isolators back on IF I HAD THEM... but i left them off the engine last time i worked on it, left them under the hood, and drove off. and my audi just didnt come with any isolators. you guys dont have to respond back at this, just im not some random idiot. and i pack a chemical fire extinguisher, they put out all types of fires.

[oldskool rich]

can i hav my thread back (yes fires are bad, best to avoid, but the chances of an engine fire are very slim)

my pump is only attached by 3 bolts, i can never be botherd to do up the one at the back and it has no rubber clamps between pipes, but still why number 2 every time? and after only a hundred miles or so? i bent a number 1 pipe to fit number 2 and its lasted the longest so far, ur theory doesnt explain the pinking


infact as im writing this im thinking to myself what if the pump has slipped round which has put the timing out, and 2 is the one pipe taking the most strain, that wud explain all. will check tomoz

[Rabbit on Roids]

check your injector break pressure... and nozzles.
unusually loud pinging is a bad injector nozzle if im not mistaken.
also, check your delivery valves. something might be messed up there, never know.

[gldgti]

can i hav my thread back (yes fires are bad, best to avoid, but the chances of an engine fire are very slim)

my pump is only attached by 3 bolts, i can never be botherd to do up the one at the back and it has no rubber clamps between pipes, but still why number 2 every time? and after only a hundred miles or so? i bent a number 1 pipe to fit number 2 and its lasted the longest so far, ur theory doesnt explain the pinking


infact as im writing this im thinking to myself what if the pump has slipped round which has put the timing out, and 2 is the one pipe taking the most strain, that wud explain all. will check tomoz

all 4 pump bolts are essential... gotta keep hte pump vibration to a minimum (if your missing a bolt it is more likely to move around).

other thing about the lines breaking - they are very hard and are in an environment where they vibrate at high frequency and are subject to pulsating internal pressure. these are IDEAL conditions for fatigue to occur. if the lines arent clamped together at all, they are free to vibrate in whichever manner they choose from pump to injector, allowing a comparitively large movement and speed up the fatigure process. the clamps and dampeners that are installed from the fatory prevent the lines from vibrating enough to limit the oscillation magnitude to below the fatigue limit for the material, giving (theoretically) infinite service life. without these, it is only a matter of time before they do break - and they will.

on the subject of the particular line breaking - because the lines are all bent in different places, the abililty of a particular line to vibrate is changed compared to other lines. it may be tht the shape of line 2 makes it particularly prone to setting up large magnitude vibrations, so it cycles out first when unrestrained.



 

[Vincent Waldon]

One of the things I try to keep in mind is that car manufacturers are extremely picky about every part they use... over the life of a model line every extra screw adds millions of dollars to a production run, requires documentation, stocking, training, inventory, etc etc etc.

In the immortal words of GM engineer Boss Kettering: "Parts cost out cost nothing and cause no service problems"

I try to remember that when I look at a design and am tempted to say "surely I don't need that"... the manufacturer was very very deliberate in the design of the little rubber and metal injector line clamps and would definitely have left them off if at all possible.

Will your engine grenade if you leave them off... probably not.  But if the same line fractures repeatedly and you don't have the clamps designed to prevent this from happening your car might be trying to tell you something. 

[Baron VonZeppelin]

In my past readings I've read of #2 being the one to most likely break.
Or the first to break.
Always usually either no isolators in place - or loose mounting bolt(s).

And here you have no isolators - in combination with a missing bolt.
hmm.........
and its happened more than once
uh huh ...

Try doing the fouled cylinder/fouled injector test by loosening one injector line at a time with engine running, and see which one(s) give the most reaction.

The one(s) with the least reaction should be suspect.
If all other engine parameters are in good order.

#2 injector "might" have small metal debris from the fuel line failures.
I'd check it at minimum.

[92EcoDiesel Jetta]

I think I know the answer to that Andrew. It's because he does not have the special 17 mm bent wrench to remove the inj lines as an assembly. Ask me how I know lol. I finally made a bent wrench.