TROUBLE while on Road Trip w BORROWED 2000 Jetta 1.9 TDI - need info!

[csstevej]

Yes it won’t move unless you have the car running or a separate vacuum source.
Sounds as if the lever is working correctly .

 

[jmodge]

Without VCDS it’s a guessing game. From the info so far, roughly jarred in potholes, pump code, truck sound, loss of power, I’d say your pump is in advanced position. Easy to verify with VCDS, never leave home without it.

“Truck sound”, Predetonation is different on a diesel than a spark knock. Does it shake more than normal? Louder, almost in a violent and angry manner?

 

[jmodge]

https://forums.tdiclub.com/data/xfmg/thumbnail/147/147413-b376183c2493fa01f448c5c87fd4154c.jpg?1652024025

I thought I had a more complete photo. In case you're a glutton for punishment, a partial photo of my Diesel purge setup. Two important things to note, a filter in the line the pump is pulling from the bottle or container, (the injection pump internally has a suction side to pull fuel from the tank and high pressure side that feeds the injectors) and in my case a steel vacuum line off a Chevy Van to prevent the translucent suction line from collapsing. Others have different methods such as hanging a bottle to gravity feed. I set my bottle above the pump and it has worked fine. Plus I needed a use for that really cool bottle. Point being, that small amount of "fuel" heats quickly and the hose can collapse draped over the bottle. that will lead to starvation of fuel and lubricant to an already warmer than normal pump. Not good, especially since that pump is somewhat questionable to begin with

 

[jmodge]

https://www.bing.com/ck/a?!&&p=da01e7550433d0b6JmltdHM9MTY4MzU5MDQwMCZpZ3VpZD0zYmQwYTBhYi1lZWQ0LTY2ODgtMWEwNC1iM2E3ZWY2MzY3NWImaW5zaWQ9NTI2NA&ptn=3&hsh=3&fclid=3bd0a0ab-eed4-6688-1a04-b3a7ef63675b&psq=alh+tdi+diesel+purge&u=a1aHR0cHM6Ly93d3cueW91dHViZS5jb20vd2F0Y2g_dj1EREJ6clRSVm1FTQ&ntb=1

probably better vids out there, but here's a quick look at the general idea

 

[Shenandoah]

Take it to a guru from the list hskrdu provided or a competent TDI mechanic. With limited tools and no VCDS, you're just guessing at what the problem is.

Eric

 

[RTIII]

[...] So, that particular function appears ok, at least viewed by text

"When Viewed By Text!" Classic!

 

[turbodieseldyke]

jmodge's photo:

https://forums.tdiclub.com/index.php?media/008e19db-4b81-499c-99ad-b96844d8c36f-jpeg.147413/full

(Test confirmed. Why doesn't this site automatically post images from its own Media source?)

 

[RTIII]

Without VCDS it’s a guessing game. From the info so far, roughly jarred in potholes, pump code, truck sound, loss of power, I’d say your pump is in advanced position. Easy to verify with VCDS, never leave home without it.

OR a shop manual! If one of these ever finds its way into my care again, I'll be prepared next time. I'm usually prepared: "Prior Planning Prevents Piss-Poor Performance!" (Not a Boy Scout - was kicked out for eating a Brownie! )

"The VCDS", I take it, is another name for the VAG ODB2 reference others have made upthread? I take it it's the VW-brand-specific ODB2 reader.

The shop I'm planning to bring it to on Thursday (or tomorrow evening) said they don't have an actual VW unit but that it can read those codes... Should I be skeptical? Watch 'em do it?

“Truck sound”, Predetonation is different on a diesel than a spark knock. Does it shake more than normal? Louder, almost in a violent and angry manner?

As I'm a person who has designed pistons for particular applications, I'd say the closest sound I've heard in my experience is a piston with too much "wall clearance" with its cylinder - only several at once, of course. Shaking? Not that I noticed, but then I wasn't looking for that, either. ... Louder? DEFINITELY. But I wouldn't call it violent or angry, just noisy.

Take it to a guru from the list hskrdu provided or a competent TDI mechanic. With limited tools and no VCDS, you're just guessing at what the problem is.

Eric

Eric, I checked, and unless there was some kind of computer error I didn't notice, there's not any entry in either the state I'm in, or the nearest state, either... I didn't look further than that!

 

[RTIII]

jmodge's photo:

https://forums.tdiclub.com/index.php?media/008e19db-4b81-499c-99ad-b96844d8c36f-jpeg.147413/full

(Test confirmed. Why doesn't this site automatically post images from its own Media source?)

Hi turbodieseldyke, I asked myself the same question!

(BTW, are you the person who pointed me at tdiclub.com? If so, thanks!)

 

[jmodge]

If they don’t have vcds, I would be more than skeptical. They DON’T know TDI’s. Yes, VCDS is VW specific, but it’s much more than a OBDII reader. It performs basic and output tests, reads data, runs and records logs, body and comfort controls all specific to VW. On top of that it is very inexpensive for what it can do compared to any OBII tool on the market, BY FAR!
ANY SHOP THAT WORKS ON VW WOULD KNOW THIS AND WOULD OWN ONE.
I paid in the area of $400 for an unlimited VIN that covers everything through 2015 with free updates.
I recommend you put a chastity belt on backwards and stuff your wallet in it before you go there.

 

[braddies]

They might have rosstech or hex-can or have a different name or maybe a snap-on unit, but the code(s) you're looking for should be a 5 digit number, and you can look them up on Ross-tech's website fault code list

 

[J_dude]

The shop I'm planning to bring it to on Thursday (or tomorrow evening) said they don't have an actual VW unit but that it can read those codes

VCDS isn’t technically a “VW unit” either (by that I mean, Volkswagen didn’t make it, RossTech did) so the shop you’re talking to may have something that will work, like braddies said above.

 

[jmodge]

Thing is, he doesn’t need someone to read codes. Almost Anybody can do that. He needs someone to read data and interpret it properly and repair it with quality parts and proper procedures without pissing money away on guesses and parts that are secured without first hand knowledge of the vendor. The Mk4 ALH is a very specific niche.

 

[turbocharged798]

Agreed. Looks like P1252 translates Commencement of injection valve: open or short to ground. So basically either the N108 located on the injection pump is open circuit or there is a wire broken somewhere. I would unplug the injection pump and ohm out the correct pins going to the N108. Looks like the problem is pure electrical. If the N108 is open then the pump has to be pulled anyway to access it. ECU now has no control of timing so that's why it went into limp mode. Its stuck on base timing.

Lots of noise, talk and suggestions in this thread. While most of them have good intentions, its very important to stay on track troubleshooting and not trying to find solution to fit the problem. OBD2 works, start there. Even P codes are useful as shown above took us right to the problem. I am worried that the OP changed the vacuum hoses and created yet another problem if they are not hooked up correctly. Its important not to shotgun problems like this.

Here's a useful thread on solving the N108 code.

Bad N108? Just making sure.

Hi guys, I have the "17660 - Commencement of Injection Valve (N108): Open or Short to Ground" code being thrown and no others. Car sounds way advanced, obviously, has no power, obviously. Plug in VAG-COM and go to measuring blocks group 4, it's stuck at around 27 degrees BTDC all the time. Last...

forums.tdiclub.com

 

[jmodge]

Interesting article, I wonder if the ohm reading changes in relationship to the position of the solenoid and if that position changes in relationship to the timing mechanism if it is stuck

 

[jmodge]

At any rate, OP is in a pickle, but things always work out somehow and troubles pass.

 

[RTIII]

To reduce thread-bloat, I usually try and bring my replies into one posting when there are many things to comment on BUT THIS TIME, I think I should jump right into this youngest one and leave other remarks for another posting:

[...] Looks like the problem is pure[ly] electrical.

That would be great, and I'm leaning in that direction myself for a collection of reasons, not least of which was the suddenness of the change - nothing gradual about it. And, I have found good reasons to reject suggestions about the muffler / cat, etc, and I now think the actual source of the baby rattle sounds is likely the top of the struts in the front suspension - quiet when loaded, noisy when unloaded. (This is a very distinct sound from the sound that's in my only partially informed view is the pistons rattling around in their bores.)

If the N108 is open then the pump has to be pulled anyway to access it. ECU now has no control of timing so that's why it went into limp mode. Its stuck on base timing.

This makes good sense to me and while I PULLED LIKE HELL on the damned connector and don't want to break it, NOBODY has told me HOW to get the connector apart and re-seated, and I've practically BEGGED people. Some say, try this, I say it won't come apart, so how? No answers!

[...] its very important to stay on track troubleshooting and not trying to find solution to fit the problem.

While "out of my element" here, on this topic, as a master troubleshooter in virtually every discipline I have any skill in whatsoever, I COMPLETELY and "violently" agree; my goal is to listen, figure what makes sense and fits into what I know, AND, when acting without full information or in ambiguity, try and focus on the easy, inexpensive, and not likely harmful as first areas of focus.

I am worried that the OP changed the vacuum hoses and created yet another problem if they are not hooked up correctly. Its important not to shotgun problems like this.

I've been working with this cloth braided hose since roughly 1977 when I got my first VW. And, while not a water-cooled fan so far, these hoses are ubiquitous in the earlier VW and Porsche vehicles, of which it is no exaggeration to say I'm a master. I assure you, ALL the hoses I replaced were failed or failing, and I left all the ones that seemed to be intact alone; I am 100% sure there were failed "vacuum" hoses that were other issues. Further, I did them one at a time, with only one exception because they just fell apart on me. However, that would be easily fixed.

Here's a useful thread on solving the N108 code.

Thanks for the link - AND your comments.

 

[STDOUBT]

I PULLED LIKE HELL on the damned connector and don't want to break it,

Negative. You don't undo the connector on the N108. The conductor along with it's insulation is part and parcel of the unit itself.
Here's a shot of the business end:

I remember hearing @jimbote repaired one of these by cutting the connection case open and re-doing the conductors.
But yeah, it's only doable with the pump out of the car.
Also, sorry but I missed your questions about disconnecting the N108's wiring.

 

[RTIII]

[...] it’s much more than a OBDII reader. It performs basic and output tests, reads data, runs and records logs, body and comfort controls all specific to VW. On top of that it is very inexpensive for what it can do compared to any OBII tool on the market, BY FAR! [...]

Sounds great - and like it's a great idea for them to have done that.

They might have rosstech or hex-can or have a different name or maybe a snap-on unit, but the code(s) you're looking for should be a 5 digit number, and you can look them up on Ross-tech's website fault code list

Thanks, Braddies, sounds good.

VCDS isn’t technically a “VW unit” either (by that I mean, Volkswagen didn’t make it, RossTech did) so the shop you’re talking to may have something that will work, like braddies said above.

This gives me more confidence, thanks.

Thing is, he doesn’t need someone to read codes. Almost Anybody can do that. He needs someone to read data and interpret it properly and repair it with quality parts and proper procedures without pissing money away on guesses and parts that are secured without first hand knowledge of the vendor. The Mk4 ALH is a very specific niche.

I agree! And I said right up front some 10 days ago that, especially at that time, I was a potential sucker waiting to be taken and needed info to figure things out. And you folks have helped move me along immeasurably - THANKS!

Importantly, when I found this guy, he was busy turning me down and I was accepting that but we kept talking anyway. As I recall the conversation, I was asking "who then", and pointed out that it was clear to me by then this was a niche vehicle, and who knows these, anyway? He said that THEY did, just have a policy against working on vehicles over 20 years old imposed by the boss. I remarked that 20 years isn't old - I work on Porsches 1948 through to about 1975, and I don't even think of the later '60s cars as old because they are so sophisticated (Porsches here, not Fords!), and even now fit so well into the modern arena - from the fundamentals, you'd hardly know they were older. And anyway, he checked out my web site - AND THIS THREAD as we got deep into conversation and he said he'd find a way to help.

He's read at least the earlier parts of this thread... I intend to point him at YOUR ADVICE!

This next one I already replied to, but for emphasis:

[...] So basically either the N108 located on the injection pump is open circuit or there is a wire broken somewhere. I would unplug the injection pump and ohm out the correct pins going to the N108.

HOLD THE PHONE: Is there any lock on the connector or WHAT?! I want to unseat it and reseat it! SIMPLE, WORTH DOING, and I don't want to break it. It doesn't seem to want to come apart. WHAT IS THE TRICK?!

Interesting article, I wonder if the ohm reading changes in relationship to the position of the solenoid and if that position changes in relationship to the timing mechanism if it is stuck

The change of an ohm reading in relation to position is THE normal way such things work. If not, it's a quite odd-ball exception!

 

[braddies]

There's a lot of information stored on the internet from the last 20 years on how to disconnect vw electrical connectors, you got that search

 

[RTIII]

Negative. You don't undo the connector on the N108. The conductor along with it's insulation is part and parcel of the unit itself.
Herr's a shot of the business end:

OH, I was referring to the larger connector that goes to the IP - Injection Pump... Or, is that not what I should try to do?

The one you show there... I've got to find it and try it! I have some time tomorrow before bringing it to the shop! If unplugging it and re-plugging it in works, YAY!

 

[RTIII]

There's a lot of information stored on the internet from the last 20 years on how to disconnect vw electrical connectors, you got that search

You mean you've never wasted HOURS searching for something only to come up empty handed due to NOT KNOWING THE DAMNED KEY EXPRESSION OR PHRAISE that helps you find the right thing? Come on man! There are tens of thousands of matches on incorrectly targeted expressions. You could just TELL ME, you know!

I figure people think "it's so simple, he's just being stupid," but when you don't know, you don't know, and when it's young you can expect it to be strong and take some force but when this old you can't!

 

[RTIII]

I recommend you put a chastity belt on backwards and stuff your wallet in it before you go there.

Damn, man, you come up with some memorably funny stuff!

 

[STDOUBT]

The one you show there... I've got to find it and try it!

I point it out here:

TROUBLE while on Road Trip w BORROWED 2000 Jetta 1.9 TDI - need info!

Since you hit a lot of big bumps just before this started, maybe the injection pump plug should be unplugged and then plugged back together. Check the contacts and wires while you are at it.

forums.tdiclub.com

But I wouldn't futs with it other than have a look at it's condition.
Same with the big one, I think that's a 10-pin connector. If it looks normal (tight up against the pump), very little point in messing with it!

 

[STDOUBT]

If unplugging it and re-plugging it in works, YAY!

The one I point out there...read again. You don't unplug it and re-seat it.

 

[braddies]

The one I point out there...read again. You don't unplug it and re-seat it.

That's the one to use the flashlight and mirror tool with right?

 

[RTIII]

The one I point out there...read again. You don't unplug it and re-seat it.

Interesting post.

I just got off the phone with the owner who's a big TDI fan - he loaned me this one because he's gotten himself a new one! (Not sure the year of his new vehicle.) And he and I discussed this connector in some detail.

He said that removing these - disconnecting them - is "counter-intuitive because you have to push IN, then squeeze to remove them!" Etc. Bizarre! He then said ALL of them of this basic design work the same, etc He opined that the older they get, the harder they are to disconnect, and he's been known to use a channel lock plyer to squeeze so he could do the in / out pull more easily. And, if I understood him correctly, said that once you've done your first one you understand it more easily.

However, I expressed extreme caution about doing anything further with them and he wasn't sure the right call either, leaving it as, "clean it more thoroughly, be SURE what you're trying to pull apart from what, and if you can get it apart and re-seat it, sure, otherwise just leave it." (meaning don't do it tomorrow AM).

So your input is timely, thanks.

 

[turbodieseldyke]

(BTW, are you the person who pointed me at tdiclub.com? If so, thanks!)

Wasn't me. Maybe that was naturallyaspirateddieseldyke.

 

[cruzetond]

I have no flipping idea how the hell you're SUPPOSED to pull those two horizontal runs (1 line, 1 hose), from right to about center off the firewall / rain gutter, but prying downward got 'em out of the way and from there I could do the work.

 

[RTIII]

Universe willing, today the 2000 Jetta goes to what I hope is a competent workshop. ... Thankfully, the owner got home from another trip last night and read this entire thread. We then reviewed the detail together. I asked, and he agreed that he'd be the one ultimately calling all the shots on what gets done, and he's agreed to pay for it.

As for the various ODB2 readers out there, he said he's quite familiar, and the best one he knows of has an example owned by a mutual friend of ours and involves not less than three computers - the one in the vehicle, the "ODB2 reader", and a workman supplied laptop, tablet, etc, and is capable of many things far beyond a simple ODB2 reader. And, HE will interview the workshop on the matter.

As pointed out in this thread, you CAN do the diagnostic work to figure it out WITHOUT said reader, but it's more time consuming, and more guesswork, which of course normally means more costly.

The work begins tomorrow, but I'm planning to hand the car off later today so I can have my morrow free to spend time helping my sister. I have one of these to install.