Injection Timing Issue - TB Change

so everything seems at top dead center, right? yet on VAG-COM, when you go to tune the fueling, it's outside the range of the green/red/blue lines. It's well below the green line...

what does mean to you TDI guys?

This is not a big deal. Pinning the pump and cam gets it close enough to start. Think of it as "coarse adjustment" VAG-COM gets you to the fine adjustment. Below the graph is retarded timing.

You need to loosen the 3 13mm bolts on the pump pulley, and then use a 22mm to turn the pump shaft relative to the pulley. Turning toward the front of the car advances timing. Toward rear, retards.

Small movents of the 22mm wrench produce BIG changes on the VAG-COM graph. Set it up toward the top of the graph.

Basically this is a trial and error procedure.

Good luck!

thanks for the reply wanders. I'm not 100% on making any kinda change mechanically, since from what the guys at Heinz told me, the injection pump is one helluva complicated bastard. I would have thought the same thing, just loosen the three bolts and move the shaft, but that didn't even come up in the converstion with the mechanics... so I left believing that moving the shaft would be bad somehow. did I get the wrong impression? can anyone else speak on the issue?

wanders have you ever advanced the injection timing mechanically?

loosen the three bolts and move the shaft clockwise a hair.

bbarbulo said:

thanks for the reply wanders. I'm not 100% on making any kinda change mechanically, since from what the guys at Heinz told me, the injection pump is one helluva complicated bastard. I would have thought the same thing, just loosen the three bolts and move the shaft, but that didn't even come up in the converstion with the mechanics... so I left believing that moving the shaft would be bad somehow. did I get the wrong impression? can anyone else speak on the issue?

Click to expand...

They were talking about the insides of the injection pump - you don't want to go there...

This is just adjusting the position of the sprocket in relation to the pump shaft... that's how the fine-tuning of the static timing is performed... I guess the guys at Heinz should catch up...

Yuri.

runonbeer said:

loosen the three bolts and move the shaft clockwise a hair.

Click to expand...

runonbeer has nailed it.

Happy wrenching

cam is retarded

Unless you removed the cam plate for the photo, the cam is retarded the way it is now.

ok good observation Frank M! last time I did the belt a few years back, I took the cam sprocket off. again, nothing was locked in place last time either. the car was also not vag-com'd last time after the TB change. I don't remember why I took it off... I just did. also, I would have thought the cam sprocket would be keyway'd. I'm clueless as to why it's not. cam timing on an interference engine is nothing to play with, but who knows maybe it's a diesel thing I don't understand. anyways, would cam timing being retarded affect how the fueling looks on vag-com. do you think I should dick around with it, or well enough alone? or do I fix it by advancing the injection pump. the injection pump has never been touched... it's exactly how it left the factory. I can ask my dad to make me a cam locking tool, I have a neat design in mind... it wouldn't be THAT difficult to do.

also, when a gas engine runs lean, EGTs skyrocket and the engine pings (detonates).... does diesel do the same? I'm assuming being under the recommended area, it means I'm running lean. am I risking melting the pistons? do diesels detonate?

excellent advice everyone!!! if possible I would totally rather just advance the injection pump (since it doesn't involve removing the TB again - I just did it twice over the last week). however, if necessary, I don't mind fixing the cam timing to not be a degree or two out, but that'll wait till springtime if that's what it's gonna take.

bbarbulo said:

last time I did the belt a few years back, I took the cam sprocket off. again, nothing was locked in place last time either. the car was also not vag-com'd last time after the TB change. I don't remember why I took it off... I just did. also, I would have thought the cam sprocket would be keyway'd. I'm clueless as to why it's not. cam timing on an interference engine is nothing to play with...

Click to expand...

Please read through Drivbiwire's timing belt replacement procedure -
http://pics.tdiclub.com/pdf/a4timingbelt.pdfto try to understand why things MUST be locked down!!! There are enough TDI-Club members in the region who own the lockdown tools that you should have no problem in finding a set to borrow...

You can get lucky up to a point with guesswork, but as you said, "cam timing on an interference engine is nothing to play with"

Yuri.


PS: be aware of a little error in that PDF: when Pete describes the final pump timing adjustment, he points the wrong way... counterclockwise rather than clockwise...

ymz said:

PS: be aware of a little error in that PDF: when Pete describes the final pump timing adjustment, he points the wrong way... counterclockwise rather than clockwise...

Click to expand...

Also be aware of another major error
Page 114
Never ever turn an engine using the cam shaft or any other pulley.
Strong forces are put on the guides or in this case the tensioner this way.

It has to be done by the crankshaft only.

ok will do... but what's done is done at this point. just wanna hear some ideas on how to get the three things back into alignment... clearly at this point since I'll have to align everything again, things won't be locked one at a time. so I'm thinking, lock the injection pump and crank since those two seem pretty dead on, then take the cam sprocket off, then take the cam locking tool and use the tool to align the cam to the head using the tool plus feeler gauges, then put the cam sprocket back on (but how do I know where to stick the cam sprocket?). like, I could be out half a tooth on the cam since there is no keyway? or should I put the sprocket back on loosely (w/o engaging the taper), and then put the timing belt back on and tension it, then once it's in place just torque the cam sprocket bolt? I already ordered new bolts in anticipation of doing this job again.

Frank M said:

Also be aware of another major error
Page 114
Never ever turn an engine using the cam shaft or any other pulley.
Strong forces are put on the guides or in this case the tensioner this way.

It has to be done by the crankshaft only.

Click to expand...

Frank, why not re-write the procedure?

bbarbulo said:

... how do I know where to stick the cam sprocket?

Click to expand...

That's the whole point: the cam sprocket can go on any which way as long as the camshaft is locked in position!!! (You actually put on the sprocket with the belt around it...) The sprocket will turn as you tighten the tensioner (ditto for the loosened pump sprocket - again, the pump shaft is locked with the pin)... once the tensioner is set, then you tighten and torque the camshaft bolt (make sure to use a counter-hold tool rather than the camshaft alignment bar (lockdown tool) to hold the sprocket in place while torquing... the end of the camshaft will break if you use only the alignment bar to keep the camshaft in place for torquing... in fact, remove the lockdown tool during tightening and loosening...). It's the friction fit of the tapered end that keeps the camshaft sprocket in place...

In your case, I don't believe you even need to remove the cam sprocket at all since you're not replacing the belt... just break it loose - still on the loosened bolt, lock down the camshaft to align it, tighten the tensioner, and torque the camshaft (and tighten 3 pump bolts - although they'll need to be loosened again for final timing adjustment with Vag-Com...)

Yuri.

ymz said:

(snip) In your case, I don't believe you even need to remove the cam sprocket at all since you're not replacing the belt... just break it loose - still on the loosened bolt, lock down the camshaft to align it, tighten the tensioner, and torque the camshaft (and tighten 3 pump bolts - although they'll need to be loosened again for final timing adjustment with Vag-Com...) Yuri.

Click to expand...

__. Yeah, Matt ("Car54") did my timing belt a couple of weeks ago. My timing was *exactly* as yours -- it took easing off the three bolts on the IP and bumping the timing a bit. Before doing that, my timing was way below the green line, too. And it took about 4 tries to get it exactly right but now it's _SWEET_!!!!! It's now at the top line, starting is much crisper and the fuel economy has gone up a good bit.

you beautiful men, I :heart: you all lol

ok will do this over the weekend when dad doesn't need the car. thanks again for all your help, it all makes so much more sense now. also getting my own VAG-COM and having my dad make the lockdown tools. will post pics later. sick of not having the right tools for the job.

So how do you turn it over, then? Drop one of the tires down and spin the other while in gear?

Frank M said:

Also be aware of another major error
Page 114
Never ever turn an engine using the cam shaft or any other pulley.
Strong forces are put on the guides or in this case the tensioner this way.

It has to be done by the crankshaft only.

Click to expand...

no chrome that won't work cuz it's an open diff. I think I tried that.

you HAVE to use the crank pulley at all times to turn the engine. it's like a 12 point 19 mm if I remember correctly.

in my case I pulled the glow plugs out to make it easier.

good morning TDIClub!! time for an update
last night, started around 6 PM, done at 10 PM... re-did the timing on the cam sprocket and injection pump sprocket. put new bolts in the crank, cam, and injection pump sprockets. I was out about one tooth on the flywheel compared to the pump.... so loosened the cam and pump sprockets, locked the pump into position, then turned the engine back about one tooth, then torqued all the bolts. now the graph looks primo, no adjustment necessary at all! got it bang on the first adjustment. cam had to be eyeballed, the tool my dad made didn't fit cuz I took measurements off a disassembled head, so I had no idea where the cam-vacuum pump slot was in relation to the head deck. but it looks pretty good! will do that later when I feel like replacing the valve cover gasket one day for fun. just gotta buy and replace the vertical engine mount bolts now, and that's it!! car is hopefully good for another 100K kms, engine-wise at least.

Sounds like you have invented a whole new procedure.

how do you mean? screwing up the timing then having to fix it?

bbarbulo said:

... will do that later when I feel like replacing the valve cover gasket one day for fun.

Click to expand...

Sorry to tell you, but there's no valve cover gasket to replace... it's integrated into the valve cover... when it goes, time to replace the whole valve cover...

Well, you're still guessing at the alignment of the cam and crankshafts, even though it "looks pretty good" - I've seen this done before... can't say I recommend it...

All the best,

Yuri.

ymz said:

Sorry to tell you, but there's no valve cover gasket to replace... it's integrated into the valve cover... when it goes, time to replace the whoe valve cover...

Well, you're still guessing at the alignment of the cam and crankshafts, even though it "looks pretty good" - I've seen this done before... can't say I recommend it...

All the best,

Yuri.

Click to expand...

With crank = 2X cam, the difference in a little bit is a bunch.

ymz said:

Sorry to tell you, but there's no valve cover gasket to replace... it's integrated into the valve cover... when it goes, time to replace the whole valve cover...

Well, you're still guessing at the alignment of the cam and crankshafts, even though it "looks pretty good" - I've seen this done before... can't say I recommend it...

All the best,

Yuri.

Click to expand...

see, I've heard this before from someone local. however, just for fun I asked the dealer for a price on the valve cover gasket, and it came out to like $22. whereas I heard the whole valve cover assembly was around the $150 mark. dunno what the deal is.... but I did get a price on it from the dealer.

ya, I know... but the car MUST be driveable and the tool just didn't fit. so... next best thing, the calibrated eye ball don't worry, making modifications to the tool monday, will dial in the cam using feeler gauges and whatnot. it's so easy to do... I'm totally not worried about it.

bbarbulo said:

I heard the whole valve cover assembly was around the $150 mark.

Click to expand...

It's not cheap, but I don't think it's _that_ expensive... I don't know what the Canadian suppliers charge for this, but www.metalmanparts.com in the U.S. sells it for U$85 shipped...

Yuri.