Re: 93 Passat VR6, suddenly won't start, melted evap->intake hose

Do a compression to rule out any mechanical problems. A few months back we had an old VR6 which the owner was no timely on oil changes and the engine was sludge up and the oil pump was partly plugged which inturn seized the cams in the head... need I go further. If there is no or low compression it can only be two things: 1-timing chain problems 2- seized cams & #1.

The car: 93 Passat Wagon GLX VR6, 150k miles > > Yesterday the car was running like a top. > > This morning I started it, and it growled for a few seconds, like when > there isn't enough oil getting to the hydraulic lifters, although I > don't recall it ever being that loud before. But it only lasted a > second, and then it was fine. > > Twice later in the day I started it, and the same thing happened, and > it went away after a few seconds, just as before. > > Later I was driving on the interstate and it was running just fine, > all signals go, no blinken lights, water & oil temp fine. I pulled off > at a store. Came back out, when to start it. It growled, stumbled, > stalled, and then refused to start again. When I crank it, it sounds > sounds growly at first but the quiets down a little as it cranks. > Sometimes it almost sounds like it's about to start, but only for a > second, then it sputters and dies. > > Under the hood I found the following potential culprets: > 1) Vaccume hose missing plug. Actually it had been missing that plug > for weeks, but I plugged it to be safe. > 2) Breather hose heater wires broken. I cobbed them back on. > 3) The hose from the evap carbon canister to the throttle body was > melted halfway through and stuck to the exhaust manifold heat shield, > since it had popped out of it's little hanger. I pinched the intake > end shut with pliars, but it still didn't start. It may have sucked in > some melted hose, dunno what that might do to the engine. Could it > prevent the valves from closing fully? > > I tried pulling codes out of the engine, but it only threw codes for > the engine speed sensor and hall sender, which it always throws when > the engine isn't running. > > I did go through somewhat carefully to check that all the major > components weren't disconnected, like the MAS and the throttle > position sensor, etc. None of them were. It just strikes me as odd > that it went from running fine to just not starting, all of a sudden. > Any clues? > > Best regards, > Jeff
Reply to
Woodchuck
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Sounds like my 91' Golf in the dead of a Canadian winter.... this growling noise, is it the starter?.. or is the engine actually turning over? Reason I ask, is because in the winter my starter freezes and makes a low pitched buzzing noise, but doesn't actually turn the engine on first twist of the key... I think I personally need a new starter (but I won't spend the money since it works in the summer and on second try in the winter)... you might have two problems, a starter and something else.... hopefully it is nothing major tho, but a 10 year old Passat... I would expect something after all these years.

Reply to
Rob Guenther

The cam's aren't frozen. I can see one of them turning by taking off the oil fill cap. Also, I got it to actually run for a few seconds, but it ran like shit. I had to mat the gas pedel while cranking it for almost a full minute, and it started lubbing and knocking like crazy and sounded like it was only running on a couple of cylenders, but it did run a little, before it stalled out. So that leads me to belive it might be a fuel supply problem, since stomping on the gas made a difference.

One thing I should mention is that yesterday, just before this happened, I was driving through a torrential downpour for about 20 minutes. Rain has never caused me problems before, but one time I drove through a BIG puddle and the car almost stalled and then ran like shit (much like when I got it almost started earlier) for about

10 minutes, but then it was OK. Could the fuel pump be shorting or something?

One other odd thing this car's been doing... When it's cold, if I rev it over ~3k, it will lose power and run like shit for a few seconds, and I have to really baby it or it will stall. After 10 seconds or so it fully returns to normal. It doesn't happen when I start it warm.

Oh I found a blown fuse. Nuts if I know which one, but replacing it didn't help. I lost the fuse box cover and they're different from the

4cyl passats. Actually I don't even think the fuse box cover is accurate. Dumb early VR6s :(

Best regards, Jeff

Reply to
Jeff Laughlin

One other update:

I think I've ruled out the fuel pump. I took off the cover in the trunk and I can hear it running when I crank the engine, so I believe it's working. Also when I removed the hose clamp from the fuel line on the fuel rail and pinch the hose slightly, fuel squirts out, so there's residual pressure. I suppose the pump could still be bad, but that wouldn't seem to fit in with the "running fine, then not starting at all" symptoms.

-Jeff

Reply to
Jeff Laughlin

sounds like ignition problems amplified when wet

  1. EARLY VR6 Distributor cap, rotor, ign. coil, plug wires (all or some)
  2. LATE VR6 Coil Pack and plug wires

just a guess

later, dave Reminder........ Before you criticize someone, you should walk a mile in their shoes. That way, when you criticize them, you are a mile away from them, and you have their shoes. Frieda Norris

Reply to
dave

...

Another update

I pulled off the intake boot. Doesn't look like gobs of melted rubber are hanging around inside the throttle body. I sprayed some carb cleaner in it anyway.

I made a makeshift spark gap out of some clip leads and tested each terminal on my coil pack, they're all making spark.

I'm fairly certain it's getting fuel into the cylenders, because vapors whisp out of the intake boot after I crank it for a while.

Is it likely or even conceiveable that some kind of major mechanical failure is the cause? It would just seem very odd that it would run fine then just not start, if it was some serious mechanical problem. I suppose I really ought to do a compression test, but I don't have the stuff and I don't want to pay to tow it to a garage and back. Maybe I'll just buy a compression tester. Is it maybe possible that the camshaft chain jumped teeth? Does the VR6 have interference valves? It does make some loud popping noises sometimes when it cranks, I've been assuming it's the engine misfireing, but maybe it's something mechanical. Of course why would the chain slip when I went to start it and not when I was doing 65 on the interstate?

Dagnabbit.

-Jeff

Reply to
Jeff Laughlin

Could you have a clogged Catalytic Converter? This will yield crappy running, especially at high rpm and odd starting since the extra back pressure messes every thing up. Pull the cat and try running the car a little bit to see if it goes away.

-Cabby

Reply to
Cabhammer

Jim B.

Reply to
jimbehning

Woodchuck,

So I bought a compression tester. I figured $40 was cheaper than an hour of labor at the garage. Here are the results

0psi 0psi 0psi (1) (3) (5)

(2) (4) (6)

145psi 150psi ?

I couldn't do 6 because I don't have the spark plug wire boot tool and the wire pulled out of the boot, and the hole is too small for pliars to fit. BUT NEVERTHELESS I am seeing a pattern here, are you? This leads me to belive there's a cam problem. But this is the cam that I can SEE turning when I take off the oil cap. No oil pressure to the lifters, maybe? If the timing chain skipped, could that cause it? Broken sprocket? WTF~?

-Jeff

Reply to
Jeff Laughlin

...

Well I've finally identified the culpret. I did a compression test, and no compression in cyls 1,3, & 5. Pulled off the valve cover, the timing chain had a LOT of slack, so much I could pull it off the sprockets and turn the cams. I pulled off the chain cover, and found that the plastic shoe on the tensioner had broken up and fallen off, and the metal under-shoe has a nice slot in it for the tensioner to poke through so it can be ground down by the timing chain. So timing chain loose, so the timing is off, so there's no compression, so I may have bent valves, and in any event I have to pull the tranny to fix the tensioner. Uh, no.

The junk yard offered me $150 for it. I guess another one bites the dust.

Thanks for the help.

-Jeff

Reply to
Jeff Laughlin

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