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what are these wires?
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95 Jetta GL turbodiesel
http://www.dubnetworks.net/dub...jetta+wire1.JPG.html
do they affect starting ability?


1983 Mercedes Benz 300SD
290,000 miles. 50K on alt fuels.
 
Location: North Shore Vancouver | Registered: October 22, 2007Reply With QuoteReport This Post
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Sorry,
I'm having some troubles orienting myself to your engine and photo.

What part is it in? Air intake?

Obviously a sensor of some sort... It kind of reminds me of a mass airflow sensor which is often used in late model gasoline engines. It could also be an intake pressure sensor, or perhaps an intake preheater.

Here is a mass airflow sensor (which I assume goes with the Jetta Diesel).
http://www.autopartswarehouse....ow+Sensor+A1+Cardone

I see lots of them on E-Bay for a bit cheaper too.

Anyway,
If you notice something like that, and are having "issues", fix it.

If you can't find the wiring connector at a junk yard or dealership, then try repairing your own.

You may need to cut the plug slightly to expose the ends, but go ahead and try to solder the ends together, then drop a dab of caulking or something on it to seal it. Or, depending on how the plug is made, you might be able to stick a bit of stranded wire up into the plug socket, or solder directly onto the contact.

And, yes, malfunctioning sensors could cause it to be hard starting.
 
Location: Oregon | Registered: October 17, 2007Reply With QuoteReport This Post
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Wait,

Where does that hose go?

It's not part of the PCV system is it (going from the air intake to the valve cover)? Now, that would be odd.

Still, I'd repair the wire if possible.
 
Location: Oregon | Registered: October 17, 2007Reply With QuoteReport This Post
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Sorry, whatever it is, is not present on my '86. It must be part of the PCV system (that's the breather hose). A peek inside the hose might solve the mystery. It's either a valve or a sensor.

Cheers,
JohnO
 
Location: Moses Lake, WA, USA | Registered: August 15, 2001Reply With QuoteReport This Post
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different perspective
http://www.dubnetworks.net/dub...jetta+wire2.JPG.html


1983 Mercedes Benz 300SD
290,000 miles. 50K on alt fuels.
 
Location: North Shore Vancouver | Registered: October 22, 2007Reply With QuoteReport This Post
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Looks very different than my '81

To make a good guess, we need to know where the hose goes.

It looks like a PCV hose (which would go to the valve cover), but it is hard to tell for sure.

Can you zoom out enough that we can see the two ends of the small hose. I'm assuming the big hose goes to the Turbo. Where is it on that hose? Before the turbo, or after the turbo?

My question is why they would put a valve or a sensor on the PCV system, unless it has something to do with the turbo boost.

I looked in my '85 to '92 Bentley manual. No help.

I'd probably try to just repair the wire.

But, if you pull it apart, look for any ID marks and numbers on the device and punch them into a google search.

Another useful piece of information is what the sensor is doing. Open circuit or closed circuit when the engine is off? Open or closed circuit when the engine is starting or running? Perhaps variable resistance?

Most of my vehicles are pre-ODBII.
However, do you have an ODBII sensor on your car?
ODBII readers are relatively cheap.

Any codes?
 
Location: Oregon | Registered: October 17, 2007Reply With QuoteReport This Post



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Location: North Shore Vancouver | Registered: October 22, 2007Reply With QuoteReport This Post
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no ODBII on this one. it's a mechanical injection.


1983 Mercedes Benz 300SD
290,000 miles. 50K on alt fuels.
 
Location: North Shore Vancouver | Registered: October 22, 2007Reply With QuoteReport This Post
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Ok,

I don't have that part in my VW ('81).
And, I can't find any reference in my manuals, 1985 - 1992.

I assume the big round thing on the right side of the engine serves as an oil filler, but also is the connection for the PCV Valve.

However, PCV Valves normally are just a small ball valve, completely passive with no wires connected to them.

The closest thing I can find on the web discusses a PCV Solenoid.

Unfortunately, I don't see a lot of notes about it.

Here is an interesting note about Jeeps:
http://jeep-forums.4wd.com/showthread.php?p=298967

So, according to the Jeep information, it is an anti-Dieseling device... put into the PCV system, and can just be cut out and removed (replaced by a pipe or hose without the device). That would more or less make sense.

Assuming it is a valve that is "normally closed", and it is opened when you start your car. Then, you don't want to drive without either forcing it to open, or removing it as there is a risk of dangerous gas buildups in the engine...

So,
What are your starting issues?

Bare Wires, of course, are bad, and could be giving you shorts. And, you don't really want to be shorting out your ignition circuit. So, if you remove the device, make sure you don't have any wires that are touching.

Anyway, if you are making modifications on your car.
Try to understand & verify what the part is.
For example, this is indicating it is a valve... That should be easy to verify if you pull it apart.

Be wary of any feedback systems that could cause other problems.
 
Location: Oregon | Registered: October 17, 2007Reply With QuoteReport This Post
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Bernie those wires are for a small heater in the hose to prevent condensation from freezing up in the crankcase ventilation line As far as I remember. They have nothing to do with starting. Cheers Dan
 
Location: coquitlam B.C, | Registered: October 05, 2005Reply With QuoteReport This Post
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^Yeah that's what my local VW wrench said as well. Funny that it started every day when it was my daily driver, yet when I parked it, it began to act up and I experience hard starts and now no start. Same mechanic said these Mexican VW's (AAZ engines) have a plastic or rubber washer of some sort behind the timing belt and these can be a problem when they expand or contract. He also said check fuel lines around the IP for tightness, must be absolutely tight, denying any air into the fuel line.


1983 Mercedes Benz 300SD
290,000 miles. 50K on alt fuels.
 
Location: North Shore Vancouver | Registered: October 22, 2007Reply With QuoteReport This Post
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Bernie the AAZ is no different from other VW & other IDI diesels when it comes to starting. It is always fuel, glowplugs or compression. If it is glowplugs plug in the block heater if there is one and after an hour or so it will usually start. If it is fuel try a shot of WD40 while cranking. You can also use starting ether but most guys don't recommend it. Compression is more difficult to easily diagnose without a compression tester. You can usually tow start the car if the compression is marginal. If it used to start recently my money is on glow plugs. Cheers Dan
 
Location: coquitlam B.C, | Registered: October 05, 2005Reply With QuoteReport This Post



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Some simple diagnostic steps that apply to my 1.6 IDI Turbo diesel VW engine. Maybe they apply to yours:
1) using a 17mm wrench, loosen ONE of the injector pipes about 3/4 turn. Keep your hands away from it and wear eye protection before 2) cranking the engine (a friend can do it for you) about 8 turns. Fuel should squirt out around the loosened nut. If it did, then youcan tighten the nut and move one. If it didn't, then there's something wrong with the injection system - it's probably losing prime and/or has an air leak.
3) turn the key to the "glowplug" position for a count of 10, then turn it off (don't crank the engine).
4) feel the glow plugs and the connecting brass strip - they should be warm. If they're not, then check for voltage to be present at the glow plugs when the switch is in "glowplug" position. If there's no voltage, then you've got a wiring or relay problem. If there is voltage, but nothing is getting warm, then you've most likely got at least two burned out glow plugs (4 plugs drawing full power will warm the brass connecting strip, 2 won't). Disconnect the brass strip from each glow plug (just do it in turn, rather than trying to take the strip all the way off) and measure the resistance to ground - it should be around 1 ohm, but not zero (shorted) and not infinite (burned out).
In my limited experience, an engine with two burned out glow plugs sound like it's trying to start as soon as the key is turned from "glowplug" to "start", but won't quite "catch". It stumbles and tries to run, but can't quite respond to the throttle. You'll run the battery down trying to start it, thinking that "this time it'll catch".

An engine that loses prime just cranks for a while without even a belch, then stumbles and stalls, and eventually starts and smokes a lot until it runs smoothly. That smoking and rough running was happening while the IP was flushing the airbubbles out of the system. Fix the source of airbubbles and that problem goes away.

My Jetta recently became hard to start and wouldn't keep running. The fuel pressure gage read zero vacuum (no resistance from the filter), so I knew it should be getting plenty of fuel. I have clear Tygon return lines that showed lots of air, not much fuel. I knew the problem was a massive air leak and finally found the water drain knob on the bottom of the filter had broken off, letting air suck in the bottom of the filter. Weird! It must have happened when I was working under the hood and somehow bumped it from the top, crushing the plastic fitting on the bottom (I don't usually tighten the bracket that is supposed to prevent this from happening. Silly me).

Does your engine have solid or hydraulic lifters? Collapsing lifters will make an engine hard to start. They collapse from age and miles, but can also collapse from the wrong choice of motor oil.

Does this help?

Cheers,
JohnO
 
Location: Moses Lake, WA, USA | Registered: August 15, 2001Reply With QuoteReport This Post
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quote:
In my limited experience, an engine with two burned out glow plugs sound like it's trying to start as soon as the key is turned from "glowplug" to "start", but won't quite "catch". It stumbles and tries to run, but can't quite respond to the throttle. You'll run the battery down trying to start it, thinking that "this time it'll catch".

Johno - Yes that' sounds like a good description of how it was a month ago. Now it just turns over and doesn't sound like it'll fire at all.

quote:
If it is glowplugs plug in the block heater if there is one and after an hour or so it will usually start. If it is fuel try a shot of WD40 while cranking. You can also use starting ether but most guys don't recommend it.

Dan - a shot of WD40 where?

A google search led me to this gem... http://www.mcc-marketing.co.uk/glow/glowplugs.html
As well as your advice, this video also leads me to suspect the glow plugs may be faulty.


1983 Mercedes Benz 300SD
290,000 miles. 50K on alt fuels.
 
Location: North Shore Vancouver | Registered: October 22, 2007Reply With QuoteReport This Post
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quote:
You'll run the battery down trying to start it, thinking that "this time it'll catch".

Oh yeah... tell me about it.


1983 Mercedes Benz 300SD
290,000 miles. 50K on alt fuels.
 
Location: North Shore Vancouver | Registered: October 22, 2007Reply With QuoteReport This Post
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WD40 gets sprayed into the air intake, then the engine gets cranked over. Better yet, have someone spray it in WHILE the engine is being cranked over. Don't spray much. It takes a frighteningly small amount of WD40 or any other liquid to hydrolock a piston and bend a rod. It also takes a frighteningly small amount of FLAMMABLE liquid to ignite in the cylidner during the compression stroke and push the piston back against normal rotation direction, also doing damage (holes in pistons, bent or broken crankshaft, bent connecting rod, acne, bad breath, dandruff, cavities, etc). Use caution. Better yet, find the actual cause of the problem and fix it.

Two things happen after one glow plug fails - 1) higher current passes through the remaining 3 remaining glow plugs, shortening their lives, and 2) the engine becomes harder to start, so the glow plugs get used more and longer, shortening their lives. Then a 2nd glow plug fails, then a 3rd. There is almost always one glow plug left intact, because after 3 burn out the engine won't start at all.

Glowplugs live in a harsh environment and don't last for the life of the engine. Expect to replace them periodically. Some brands last longer in particular engines than others. Some are more expensive than others. The ones that last a long time in my engine probably won't in yours, so I can't recommend any particular brand. If yours are easy to change, then I recommend buying the cheapest ones you can find (check dieselVW for good deals). If they're as difficult to change as mine, then buy the best ones you can. Ask other owners of the same engine what they recommend.

I'm surprised that the PCV hose has a heater in it. I've never seen or heard of such a thingy. Typical VW I suppose - brilliantly designing some parts for the real world, but still making the worst door handles of all cars.

Cheers,
JohnO
 
Location: Moses Lake, WA, USA | Registered: August 15, 2001Reply With QuoteReport This Post
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I just had another look under the hood. All metal injector lines are wet with fuel at the tips where they thread onto injectors.
Cycling the key and engaging the glow plug circuit did not heat up any of the plugs or the copper strip at all. These glow plugs are hard to get at and look like they are going to be hard to get out. My 12mm wrench needs to be about twice as long as it currently is to make things any easier. Plus the metal fuel lines to the injectors are in the way to boot.
Bosch plugs are $17 CAN each at the first place I called. Lots in stock.
Onward.


1983 Mercedes Benz 300SD
290,000 miles. 50K on alt fuels.
 
Location: North Shore Vancouver | Registered: October 22, 2007Reply With QuoteReport This Post
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Bernie call me and I will walk you through the process of diagnosing and changing the glowplugs. cheers Dan
 
Location: coquitlam B.C, | Registered: October 05, 2005Reply With QuoteReport This Post



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Glow plugs are relatively easy to test...
If they suck down juice,
They're probably ok.

The Bus Bars are a bit of a pain.

If you remove the bus bar, you can get a general indication of the health of individual glow plugs by touching a hot wire to the tip of each one. If you get a healthy spark, it is likely ok.

A really good battery does wonders.
I had an old Ford Pickup that a neighbor said I could have if I could drive it away.

Took out the dual batteries...
And threw in ONE Sears Diehard Marine PM-1 Battery. 1100+ CCA's... and the thing just fired right up.
http://www.sears.com/shc/s/p_1...ame=Marine+Batteries

Never underestimate the value of a good battery.
 
Location: Oregon | Registered: October 17, 2007Reply With QuoteReport This Post
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^I use deep cycle marine batteries as well in both my vehicles. Spinach brand. Local boatyard has really good prices.

I have tested the plugs for resistance and all 4 gave a consistent low reading so I think it's not the plugs. Have confirmed I am getting 12v's at the start of the copper connecting strip. Re-attaching that copper strip has got me stumped right now. I can't see how to get my hand behind the IP in order to re-attach the bolts on the ends of the glow plugs. Metal fuel lines are already removed.
quote:
Disconnect the brass strip from each glow plug (just do it in turn, rather than trying to take the strip all the way off)

Should have heeded this advice.
 
Location: North Shore Vancouver | Registered: October 22, 2007Reply With QuoteReport This Post
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