Need some TDI Guru halp! (long winded)

Alrighty so I'm a TDI newbie, but I have spent maybe 60 hours into my TDI before realizing the motor was dead.

I'm torn about what to do and what could be wrong with my car besides it needing some motor work or a whole new motor.

The fuel injection pump died which then cause my engine to die and lose compression. It started to windmill after several attempts at cranking it. After spending COUNTLESS hours researching online and troubleshooting it, installing a used, but good, injection pump along with a bunch of other stuff, it finally dawned onto me that "this fast cranking prob isn't normal", so I called a shop and I was informed that if it's windmilling then there's no compression. So there's that.

I only had the car a couple weeks and was sooo happy to have a 5-speed TDI Wagon because my current daily is a V8. I'm pretty mechanically inclined, but diesels as I learned are a bit of a different ball game. I am now more or less not a total newbie. I work on Audi's and VW's, but the gas versions, so I have plenty of tools, VCDS, etc.

So bottom line is I want to possibly keep the car if all I will need to do is buy a new motor or possibly just replace some of the internals, but what I would really like some help on is figuring out what exactly could have caused my motor to die (besides the obvious lack of compression) and what needs to be replaced if not the whole motor itself?

Would greatly appreciate any input. Hail and praise you TDI guru's, I have a whole new appreciation for you guys after spending so many hours on this car haha.

EDIT: The car in question is a MK4 Jetta with an ALH motor.

Not understanding how a failed injeciton pump can cause an engine to blow up like that and have no compression. where is the compression failed? Do a leak down test and find out.

Could you give us a bit more information about the IP failure? Did the pump seize and cause the timing belt to lose some teeth, or did it just stop pumping fuel to the injectors?

Was the engine still in time when you took the pump off?

Have you examined the timing belt and checked the cam followers for signs of cracking?

Now for the cheap and easy thing. Check to make sure the ASV is open. This is the valve on the intake manifold where the pipe from the intercooler connects.

Let us know what you find.

Is the timing belt intact?

When was the timing belt last serviced? Having more of a location than "There" may also help us help you to someone who can help.

More accurately, the already failing fuel injection pump was cleaned, wasn't primed, and that's when the car ran for 15 seconds and then died. It sputtered and almost fired up a few times but then started to windmill. The car has been sitting for 6 months now, I'm just torn because I want to keep it but maybe I need to just sell it. Fully loaded 5-speed wagon from the original owner is hard to let go of.

The timing belt was about 10k miles, 2 years old. The believe the IP seized, it was definitely not pumping any fuel to the injectors. I checked the ASV. I did not check the cam followers, but I can do so within the next couple of days.

I am in Maryland. Changed my loc for ya.

The engine was still in time when I took the IP off. I bought the proper tools to hold the cam in place.

I had already sold the old injection to someone for a core and it's currently slightly torn apart with the timing belt off and the cam cover unscrewed. I planned on getting in there to see what had gone bad but the weather and life didn't allow for that so I'm not sure what can be done in it's current state to help diagnose what may be wrong with the engine. But I did a whole hell of a lot of troubleshooting before getting to this point so ask any questions you have and I will do my best to answer.

Compression test would be a great next step, to get to the bottom of this "windmilling" you're hearing.

As posted above, a misbehaving IP is very unlikely to have caused your engine to lose all compression... so something else is likely going on.

Unless the pump did seize and cause the cam sprocket to rotate, making the engine lose time. Pull the valve cover and look at the lifters for damage.

Could be...although in my experience TDIs with messed up cam/crank timing lock up solid...as opposed to windmill.

I would suggest that the OP find a tdi Guru to asses the situation before any more work is done.

The car is currently in Rockville. I'll try to take a peek at the lifters sometime this week.

Prior to the engine sputtering to it's death I cleaned the IP (did not prime it), re-routed the vacuum lines because for some reason they were routed horribly out of whack and cleaned out the intake manifold which had TONS of sludge. I did remove the manifold prior to cleaning it. I ran vagcom on the car and it came back with a code related to the IP. I can't remember the code since this was last summer, but I researched it online and that's what spurred me to check out the vac lines and clean the IP and manifold along with checking the ASV.

The first week owning the car it never ran to it's full potential. Initially I thought that's just how a TDI was but then realized that's there's no way it runs this crappily and that's when the IP code popped up.

I haven't touched the car since last summer. The belt did not look anywhere close to the age that's on the maintenance list. I kind of think it slipped a bit.

boostedwagon said:

The belt did not look anywhere close to the age that's on the maintenance list. I kind of think it slipped a bit.

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This could definitely be an issue...

So with that being the possible cause for no-start, if I continued to crank it over could it have cause any damage internally, valves, piston smack, being a tooth or two out of time?

It's an interference engine, meaning if the cam/crank timing gets too out of whack valves meet pistons with very expensive-sounding banging noises.

"Too out of whack" is not very much, as things are very tight to get to 20:1 compression.

Hard to say if "a couple teeth out" is enough... since "a couple teeth" sounds like an estimate as well.

Might make sense to track down a good mechanic with TDI experience and the proper alignment jigs... who can check out the timing carefully.

And yup, if you suspect the timing is out probably wise to not turn it over.

boostedwagon said:

So with that being the possible cause for no-start, if I continued to crank it over could it have cause any damage internally, valves, piston smack, being a tooth or two out of time?

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1 tooth no....2 or more yes, even just cranking it over on the starter would compromise the valves for sure if they contacted a piston.

Well I just got done reading the whole thread and I'm confused.
I even have to question the original assumption of dead IP. And what did the IP cleaning entail?
From what I can tell, the engine is not out of time. You have the 3 bits lined up thru all this.
Might be time to back up and re-assess.....

I'm with Bob. Need to rewind here.

There's too much room for making assumptions, too many gaps in the story.

Car ran when you bought it? For how long? You then started poking at the IP (and assorted?) thinking that was the reason why it wouldn't start (after it once had, and had run? what happened to cause it to no longer run?)? WHAT CODES DID YOU FIND? NOTE: rarely will an IP problem result in non-starting; a problem with the IP's fuel shutoff valve, however, isn't all too uncommon.

Chasing tails here...

For sure, intake clogging is going to result in horrible performance (I can firmly relate here as my car's performance, my first TDI, was horrendous, so much so that it was worse than my 1990 Toyota Corolla!). BUT, it will NOT result in a non-running engine (or even a hard-starting one).

Always, do data gathering first. Now that a bunch of stuff has been messed with it's impossible to know whether something was preexisting or has been introduced.

If the engine can be rotated manually w/o any apparent problems (as has been noted, doesn't take much for an interference engine to demonstrate why it's called such) THEN one can start to really dive in. BUT, what were/are the codes? Keep in mind that codes are general guides only, they are not a substitute for proper troubleshooting to verify what parts need replacing or adjustments needed. Again, if no problems manually rotating the engine then, with any codes, look at the Car won't start troubleshooting thread. If no interference has occurred then perhaps running a compression test would be the next data gathering activity one should perform.

And of course, the state of the TB! One would hope that it's not crapped out (and fingers crossed that someone didn't slap a TB job on an engine that had encountered an event [which wasn't properly addressed]). Jumping on this task, however, would be premature without knowing the real state of this engine.

After re-reading this thread...I would also agree with both "Oh's".

And I will restate my first post in this thread...
The OP needs to find a competant tdi guru to assess the situation.

Based on the OPs comments in Post #9, the TB is off and I believe the IP is off as well. And, based on other comments, all this work and diagnosis he did was "last" summer!

So, to the OP, is what I've stated above the current status of the engine?

The car was in time and I'm well aware of how an interference engine works, however, the tolerances vary by car and I was merely wondering if they are much stricter on the ALH. I appreciate the feedback and I understand that some of you might be confused by the whole "story". The car has sat untouched since last summer, not "last" summer. Since July of 2017 if that is more precise for you.

Always, do data gathering first. Now that a bunch of stuff has been messed with it's impossible to know whether something was preexisting or has been introduced.

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This is pretty spot on and I am almost certain that the cause of my issues is the timing belt slipped due to the PO not being completely honest about it's age. He was an older gentlemen in his 60's and he had the factory pamphlet full of hand written documentation with mileage and dates. I did not expect him to BS that, shame on me for not double checking.

Again, this was all done July of 2017 so I'm doing my best to remember specifics. The code was related to the IP and I believe it was for the shutoff valve or the valve/sensor/something? that sits on the bottom of the IP. After scouring the "Car won't start troubleshooting" thread I went through everything and did everything properly but it was already too late.

1 tooth no....2 or more yes, even just cranking it over on the starter would compromise the valves for sure if they contacted a piston.

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The engine was originally not out of time, but as I was installing the new IP I noticed that the timing marks that were on the belt was no longer lined up with the cam sprocket and it was off by IIRC not more than 2 teeth. Pretty much this was all I needed to see but I will definitely dig into it deeper when time allows.

I even have to question the original assumption of dead IP. And what did the IP cleaning entail?

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No fuel was getting to the injectors. I think it was my cleaning of the IP along with not priming it that killed my IP. It was after almost everything I did before realizing that these TDI's are very delicate with their external injection pumps.

So, to the OP, is what I've stated above the current status of the engine?

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The current state of the engine is missing an IP, valve cover unscrewed, cam lock bar currently installed and timing cover off.

And I will restate my first post in this thread...
The OP needs to find a competant tdi guru to assess the situation.

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At this point anything a TDI guru can check for I can also check for. I'm far far from a guru but I learn quick and I've spent a tremendous amount of time on my car and reading a lot of the info that is out there. I will for sure get to the bottom of this and keep you all up to date. But don't expect that anytime soon!

My goal of this whole thread was to seek help in determining based on my troubleshooting and spotty story that if a head rebuild is sufficient to get me going or did I screw up some rod bearings by continually trying to turn my engine over after it was out of time and getting another engine is more cost effective and the better option.

My apologies for any spotiness and again thank you for all your feedback and input!!

Newbs. Always start with the basics and go from there.