hard cold start after injection pump rebuild (EuroVan TDI (AHU) conversion)

[evinor]

Hello,

I have a 1999 EuroVan TDI conversion (converted by Slavic out of Vancouver, WA in 2013) with an AHU engine and manual transmission. Took it to my mechanic (Alex's Garage in Eugene, OR) back in the fall to get the valve cover resealed, and they noticed that the injection pump was leaking diesel. Couldn't find anyone local to do a rebuild, so the pump got shipped to Diesel Fuel Injection Service out of Portland, rebuilt, then shipped back (van ended up being out of commission for something like six weeks). After reinstall of pump, the van is experiencing hard cold starts—if left overnight or longer, it takes ten to thirty seconds of cranking before it will turn over (then puts out quite a cloud of smoke (sometimes even including a smoke ring)). Once it's up and running, it will start right up if you turn it off for a while then come back and start it. Mechanic has checked everything out (including removing the seat (seats?) to get at the fuel tank), and they think it must be that something wasn't done right with the pump rebuild. So, proposed solution is to take the pump back out, ship to Portland, etc. (so van will be out of commission for a while again). Thought I'd post here in case there are other thoughts about what might be going on.

Thanks for reading!

Doug in Eugene

 

[Vince Waldon]

What colour is the smoke?

White is generally unburnt fuel, suggestive of the timing being out of whack... which would also cause hard starts when cold.

 

[evinor]

Thanks smoke *is* white . . . mechanic thinks what's happening is that air is leaking into the fuel system somehow when vehicle isn't running (but he's checked everything he can think of for air leaks, so I guess his thinking is that something with the rebuilt injection pump is the source of the leak).

 

[jmodge]

Try hanging some type of auxiliary fuel container with a gravity feed and separate fuel filter directly to the pump completely bypassing the vehicle’s feed system. That should tell you if it’s in the pump or between the pump and your vehicle’s tank.

 

[Vince Waldon]

So how's the timing? Hopefully your mechanic has double-checked and ruled this out?

 

[03Golfer]

Try hanging some type of auxiliary fuel container with a gravity feed and separate fuel filter directly to the pump completely bypassing the vehicle’s feed system. That should tell you if it’s in the pump or between the pump and your vehicle’s tank.

I would definitely try this. I'm assuming there's no electronic lift pump on the van?

 

[d24tdi]

Bingo on Vince's post.

Don't mess around with ANYTHING else until you have verified pump timing.

Based on your notes about the garage, doesn't sound like they know their TDIs. If they thought there was any chance whatsoever of finding someone "local" to rebuild a TDI injection pump, then that probably means it was the first one they had ever touched. There are only two or three (last I checked) fuel injection shops in the COUNTRY that are equipped to overhaul the TDI VE pump. Fortunately DFIS in Portland right up the road from you is one of them. They do excellent work. I have installed dozens or maybe hundreds of their pumps and never had a single one have to go back. The rebuild process they have to do in order for Bosch to certify them for working on those pumps involves a great deal of testing on advanced bench equipment after the pump is assembled. Every single pump has to meet a long list of performance specs. For one to go out the door working less than perfectly would be highly unlikely. Always possible, but the situation you describe makes me much less suspicious of the pump and more suspicious of how and by whom it was installed.

Ask the shop the simple question of what tool they used to verify injection timing and report back to us what the answer is. That'll reveal all the answers needed to determine what the issue is.

(Hint: if the answer is anything like "we lined up the timing marks" then you need to get the van TOWED to a more capable specialist, and don't turn the key again until it's in the hands of someone who can confirm not only timing, but also the other aspects of the timing belt installation.)

 

[d24tdi]

Definitely don't let this mechanic take anything else apart in the fuel system or take the pump off again. Don't forget that you had a good running van before they started working on it. Why would there be an issue in the fuel tank now when there wasn't before? This issue was caused by the work that was done on the areas of the engine they touched. Tearing apart your interior chasing a nonexistent fuel pickup problem is only likely to create new issues elsewhere.

Classic move of an ignorant mechanic dealing with a diesel engine that they don't understand, when it's running poorly because they assembled it wrong with incorrect methods and equipment, is to always suspect the injection pump is bad. I have seen cars (TDIs and others) that had the IP replaced over and over, sometimes a half dozen times in a year, sometimes with sets of injectors being replaced as well, LOL...... each time the mechanic installing with no timing equipment, and believing he keeps getting bad pumps and injectors, over and over again. Hard and smoky cold starting is textbook retarded timing symptoms. There are other possible causes but this is by far the most likely given the recent repair work.

Just saying this because if they try to convince you the freshly rebuilt pump is bad without first having their installation process checked out, you'll end up wasting lots of time shipping a perfectly functioning injection pump around the state. Don't listen to it until you have confirmation that they have done their steps by the book, no corner-cutting. Mechanics can be attracted to shortcuts like paint pen markings on timing belts that have worked great for them for many years on all different types of engines, and it can be hard to talk them out of things they believe are rock solid approaches. They don't work on a TDI.

 

[evinor]

Thanks a lot for these helpful replies! What tool *should* they have used to verify injection timing? Also, are there any shops near Eugene, Oregon that know their TDIs that people recommend?

 

[d24tdi]

The timing process involves use of specific VW/Audi-oriented diagnostic software that can enable the "basic settings" timing mode in the engine control unit (with engine warmed up and idling), and then read the output of the needle lift sensor in the #3 injector to provide a timing value. Most of us (and most qualified shops that are capable of servicing this engine) use a program called VCDS that is the best available tool for this, but there are others out there that can do it (Snap-On and other professional diagnostic platforms, etc) if they have the right software packages installed. That's for checking timing. There are also a couple of locking tools for setting the mechanical timing of the engine (cam and IP) that are required anytime the timing belt comes off.

I could go further but the bottom line is it's a unique and specialized process, having nothing in common with the timing procedure on almost any other engine out there (possible exception of something like a 6.5L General Motors diesel). It's not rocket science -- in fact if one wishes to understand how it works and what it's about, it's easy. But if one doesn't realize that it's necessary or tries shortcuts, it's an endless struggle for them and their customer.

As the customer of a shop, you shouldn't have to ask these questions or know the things I just said above. You don't want to end up in the position of trying to educate a professional mechanic about this. If you are going to have to learn the in-depth process of setting IP timing on a VE era TDI, and then play a game of "telephone" trying to teach your mechanic how to do his job, then you'd be better off just doing it yourself. It would be easier, cheaper, faster, and more likely to succeed. But you don't sound like you want to wrench on this van yourself, understandably. Given that, your best option would be to either take it to someone who is well versed in these particular engines, or tell your mechanic to come here to TDIClub and do some reading or ask some questions, if he's humble enough to learn from an enthusiasts' forum (although we do have quite a few professional mechanics on here who generously share their expertise as well).

Once he understands the process and why it matters, he'd then need to make an investment in the necessary diagnostic equipment and the locking tools for the IP and cam, if he doesn't yet have all of those items. Alternatively, if he has access to software like Mitchell (or wants to buy a Bentley repair manual for the car your AHU engine came out of, which is a 1996-97 Passat TDI or 97-98 Jetta TDI), the service info is in there... but it will refer to using the factory VW diagnostic tools which no one has. The benefit of the timing tutorials on this website is that they will provide instructions for doing it with VCDS.

One way or another, just make sure a professional mechanic is not climbing a learning curve at your expense (money and/or time). If that's what you're up against, go somewhere else, or tell him that if he wants to correct it himself, he should rent you a replacement vehicle while he figures out how to solve the issue he caused and call you when it's fixed and ready. Make sure he re-timed the camshaft correctly as well, if necessary, and that he understands the correct process for tensioning the timing belt. That is what I was referring to when I suggested not driving the van if there is any doubt about the timing procedure that was used. Your worst case scenario is that if he really botched the job and the timing belt was installed or tensioned incorrectly, total failure leading to engine damage could be not far down the road.

Not familiar with the Eugene area but you could post an inquiry in the West Coast regional section of the forum to see if folks in that area have recommendations. There used to be a directory on here of trusted TDI mechanics but don't know how up to date that is anymore. No doubt Portland has shops that can do it. Having the van towed a hundred miles to a capable specialist is well worth it, vs the "convenience" of a local mechanic who is not qualified.

 

[d24tdi]

Before I sound too harsh or cynical, I should note that although there are reasons to be suspicious, we don't yet know that your shop hasn't already done all this. For all I'm aware, they did everything right, using the right process and equipment, and the problems could be due to an unrelated coincidental fuel system issue upstream, or due to a faulty rebuild by DFIS. Unlikely but always possible. So certainly not trying to point fingers without evidence.

That's why I suggested just simply asking them what tool they used to check the injection pump timing. If they innocently answer that they lined up the marks perfectly yet it still just doesn't run right, you know your answer. But if they say that VCDS showed a basic setting timing value in the 50s or 60s between the middle and upper lines, then they know what they're doing and their efforts to dig elsewhere or point the finger back at DFIS could be correct.

 

[Nevada_TDI]

I have done business with DFIS, Portland for many years, and have never had a bad experience.
Mark knows VW TDI injection pumps and can walk you through many problems on the phone.

 

[cumminsfromthecold]

Thanks for posting this.

I am having the exact same issue and symptoms with the '97 1Z. I have adjusted timing numerous times. I havent isolated fuel yet. Perhaps today. Smoke is white. It ran for about 200 miles, hard starting each time as you describe after every overnight. Then it sat for a weekend, and since then, I cannot get it to start. DFIS rebuilt it as well.

Question for d24tdi: with VCDS connected during the cranking, what can I read to verify appropriate timing (if anything) and injection functionality?

It's your point exactly that troubles me: "Why would there be an issue in the fuel tank now when there wasn't before? ... Tearing apart your interior chasing a nonexistent fuel pickup problem is only likely to create new issues elsewhere."

 

[d24tdi]

@cumminsfromthecold your issue sounds like it could be something different than what the OP is dealing with. Similar symptoms but given that you have conclusively verified timing, and that your engine doesn't start at all now, you may be dealing with a fuel delivery (loss of prime) issue unrelated to the IP rebuild (or maybe related only in the sense of a fuel line connection problem from the installation). Or a failing crankshaft timing gear is another possibility. Did the IP timing keep moving around and you'd have to reset it? If so timing gear problems could be what you are facing. That will eventually lead to very hard start or no start.

Check the injector overflow line connections too, those can be a source of air leaks and loss of prime if they are old/brittle or didn't get back together right after the IP was replaced, though you'd probably know it if they were causing your problem because they would leak diesel when running and you'd smell it..

Sudden onset of hard/smoky/no cold starting (by that I mean, a new problem occurring on an engine that is already known to be otherwise healthy in terms of good compression, good injectors, good battery and starter, no failure of engine control systems/ECM power supply, etc) is generally traceable to only three things, that can be isolated from each other via simple diagnostic steps as below:
- IP and/or cam timing issue: in this case you'll observe immediate fuel delivery to injectors if you crack a line nut open, AND +12v to glow plug harness in cool weather, but the engine will not fire. It will generally make lots of white smoke when cranking but will either be unable to start or will start only after extended cranking, and may run poorly/smoky for a while after starting. AFTER starting you can confirm pump timing out of spec with VCDS, and/or can confirm cam timing with cam locking tool. the IP locking tool is useless for anything other than getting IP timing to general ballpark so it won't do much for this.
- loss of glow system function: in this case you'll have fuel delivery to injectors but no 12V to plugs in cool weather. TDI engine will almost always still start without glow plug function except in the deepest winter cold. But will be rough and smoky for the first minute or so.
- loss of fuel system prime: in this case you'll have no delivery to injectors when cranking, or very weak delivery/air foam. usually can regain prime with some effort or assistance of force-fed or gravity-fed fuel supply to fuel filter (never go direct to pump and bypass filter unless you want to wreck your IP and injectors!). Sometimes will also have external fuel leaks when running depending on where it's leaking from.

Three completely different causes that can look somewhat similar to the untrained eye but require different troubleshooting paths to identify and fix.

@cumminsfromthecold no, no way for VCDS to read timing during cranking, it's more or less blind at that point with such low RPM. that's why some folks set the pump towards the advanced side of the static window for easier cold starting. Once it's running you can get various indications from measuring blocks (advance piston duty cycle and requested/actual timing advance), and from basic settings.

 

[cumminsfromthecold]

Thanks d24tdi, that's very helpful. I did get it running, but still with complications. Details posted on my build thread. Don't mean to hijack here.

evinor, where are you with getting the EuroVan issues resolved?

 

[evinor]

Sorry for taking so long to provide an update! So Alex's Garage confirmed that they have repeatedly done the appropriate timing check. I know that they've been in touch with DFIS a bunch about the situation, and DFIS concluded that the pump should be sent back to them, so I guess DFIS is relatively satisfied that the likely explanation is something with the pump itself. I dropped the van off with Alex's again a week ago yesterday, and the plan is for them to remove the pump and send it back to DFIS. So, will post another update when it's returned and back in the van (likely in a number of weeks, though I'm hoping DFIS will prioritize things in light of the situation). Fingers crossed!