Hard start and smoking after timing belt change

UhOh said:

steve, the ONLY time that you won't have an instant start is if you somehow managed to introduce air into the fuel system (fuel line/filter disturbed). I don't see it readily happening, but cannot say that is can be ruled out. BUT, that's for the initial start, subsequent starts should not be affected (unless fittings weren't tightened sufficiently).

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Very true

The last timing belt job I did when I lit it up and got it warm enough to check the timing was literally BANG ON in the middle of the graph.

I'm not usually that good, but I've never had it OUTSIDE of the two bars. Then again I do it "by the book", and it's always been acceptable -- but to have it literally on the line without any adjustment at all was quite surprising.

But if you don't have VCDS (or the dealership VAS tool).... you're guessing.

Many years ago I responded to an inquiry on here from a local garage about an A3 that wouldn't start. I found the problem right away and noticed it was out of time, so I timed it while I was there. A year later the guy's son picked up an A4 and wanted to do the timing belt on it but didn't have the tools. I loaned him the tools and the Vag-Com, but he called a few days later and said the car wouldn't start. I responded and checked the timing, which was off. The 'mechanic' didn't follow the procedure I printed out for him. The next day the guy said he redid the timing again but it still wouldn't start. When I asked about the timing procedure, he said he knew what he was doing and started arguing with me, listing off his many mechanic certifications.

I redid the timing, specifically the cam that he never released, reached in, and the car fired up as soon as I touched the key. I hadn't even timed it with the Vag-Com yet.

My bet is this garage did just that, didn't release the cam when they set the timing. It's common when doing the Mark-n-Pray timing belt swap I've seen a lot of people do, including reputable garages.

Unfortunately, I still don't have my car back. I have printed the large PDF on doing the timing belt. It looks like I might have to buy the tools and redo the timing. I am going to try to pay someone else to redo it because it would probably be cheaper and faster, but I am not sure another shop will touch it after the first shop did it.

Twinkieflyer said:

Unfortunately, I still don't have my car back. I have printed the large PDF on doing the timing belt. It looks like I might have to buy the tools and redo the timing. I am going to try to pay someone else to redo it because it would probably be cheaper and faster, but I am not sure another shop will touch it after the first shop did it.

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Any decent shop ought to be able to deal with most anything. The ISSUE is whether they can properly warn of possible scenarios and get you to understand the potential costs. There is a possibility that any shop could run into something that they say is unrepairable, or repairable only with excessive costs. Good idea would be to understand what should/can be done should it get to that point.

I'd also expect any good shop to attempt to fully assess the state of your vehicle before attempting to quote you price ranges. Here you would need to be upfront about any suspicions. It is only proper to expect to shell out for someone to perform proper diagnostics. Folks here should be able to somewhat vet the results (as long as it is know what was done).

I'd have it AAA'ed to the nearest guru. If your shop has the proper tools then have them show you their vag com or tell you who they subbed the job out too.. Sounds like the timing is off a tooth and they have moved the pump as for to one side to get it to at least run decent, they might have had it off a couple more teeth and tweaked a valve seal??(white smoke) I did my own TB boy 60K ago and do not remember the exact procedure to figure TDC but I remember Whitedog and Oldpoopie had a good post on it. Good luck..

The car is certainly drivable. I drove it over 500 miles and it runs fine after all the smoke signals starting.

I looked on the section with names of shops, the only one near me in Floyd VA burned down 3 years ago. There was one in Fredericksburg VA, but that is 4 hours away.

I realize I am probably going to pay for this job again, but I really like the car. I should probably just spend what is required time and money wise and do it myself.

KLXD said:

I'll second what Genesis says.

Car started fine, they worked on it, doesn't start fine anymore. Should be obvious even to them that they didn't do it right.

To me what would make a shop rate as excellent is not the work they've done that was not a problem it's how they handle an issue like this.

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^Proof that they are NOT a good shop...period.

Genesis said:

IMHO if it's not running right after the job then you need to verify ALL THREE of the timing locations (cam, crank and IP) are correct.

If the cam and crank are NOT aligned you may be ok in terms of damage, or you may not. The amount of slop before you're not is, if I remember correctly, only about 7 degrees -- which isn't much!

Any time something appears to be done wrong the only SANE thing to do is check ALL OF IT. This will require both the lock plate for the cam ("one" special tool) and a new seal ring for the vacuum pump (or it WILL leak!) but is otherwise not a big deal to check.

If it's JUST the IP that's off it's easily fixed. My problem with this sort of issue is that there's no excuse for it being wrong, and thus if it is I assume EVERYTHING is wrong until proved otherwise.

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^ Yup!
Take it to someone that knows tdi's

Twinkieflyer said:

.

I looked on the section with names of shops, the only one near me in Floyd VA burned down 3 years ago. There was one in Fredericksburg VA, but that is 4 hours away.

I realize I am probably going to pay for this job again, but I really like the car. I should probably just spend what is required time and money wise and do it myself.

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I've had people drive 10 hours to have me work on their cars, every one went away happy. I'm not saying bring it to me, I'm saying it's worth the drive and effort to have it done correctly.

Twinkieflyer said:

The car is certainly drivable. I drove it over 500 miles and it runs fine after all the smoke signals starting.

I looked on the section with names of shops, the only one near me in Floyd VA burned down 3 years ago. There was one in Fredericksburg VA, but that is 4 hours away.

I realize I am probably going to pay for this job again, but I really like the car. I should probably just spend what is required time and money wise and do it myself.

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If you have the money, get it done by the guru.
If you really want to learn this finicky process that you'll probably do once and you have two weeks to spare, a 200$ vagcom license and $300 worth of special tools, and a heated shop to do it in; by all means..

Well, I got the car back today. It started in one rev from cold. Ran a bit rough for a few seconds but it was very cold.

I had sent several articles down to the shop:

http://pics3.tdiclub.com/articles/pdf/a4timingbelt.pdf
http://www.myturbodiesel.com/threads/no-start-after-timing-belt-change-any-ideas.18519/page-3

The second one seem to concentrate on recheck of the job.

What I was told was that the thing they did differently related to not tightening the cam bolt until the belt was tensioned and then removing the pin. I might not have completely gotten right what he told me, but the results were clearly good. Car starts now instantly when cold.

I really appreciate all the help and advice I have received here. I probably should have found a shop that did lots of these to start with. It was really a pleasure getting back in the car and driving. I don't know exactly what it is, but I really like this car.

Thanks again,
Bill

Sounds like the original shop tightened the camshaft bolt before tightening the tensioner: when the tensioner was tightened the cam's timing was thus retarded(?).

Same shop, they just used the info and redid it. Yes, the cam bolt is what he said got them.

Well, that's a good outcome. Your trusted shop comes through, your car gets fixed and they learn something in the process.

I don't want to rain on the parade but you won't know that things are OK for sure
until you put about 10,000 miles on that TB job. The smoking is not a good sign.

I'm thinking they're in CYA mode and the true story will never be known.

Let's see. Cam bolt tightened then belt tensioned... If cam locked you get late cam timing and undertensioned belt. If cam lock removed still late cam but maybe only a little undertensioned belt.

Either way I don't see that causing hard starting unless the pump sprocket was never loosened then you'd likely get late pump timing too as the slack was taken up.

Of course we know late cam timing can be a big problem if it's too far off.

So if the cam was off by not being released, is the number of degrees likely to have caused the valves to hit the pistons?

It ran pretty well that way, just very hard to start. Is there any way to tell?

I do differential compression checks on airplane engines where we check cylinder leakage. Is there a way and a port to do that on a tdi? Can an adapter be used on a glow plug thread?

Yeah, glow plug adapter. Diesel gauge (over 500 psi), remove wire from fuel solenoid on pump.

Thing is the valves are parallel to the cylinders and a piston hit can compress the stem but not cause it to leak.

Could look at the exhaust cam followers. They should show some cracking if there was a valve hit.

You're probably ok. It's the nature of these forums that we always speculate about the worst case

KLXD said:

Yeah, glow plug adapter. Diesel gauge (over 500 psi), remove wire from fuel solenoid on pump.

Thing is the valves are parallel to the cylinders and a piston hit can compress the stem but not cause it to leak.

Could look at the exhaust cam followers. They should show some cracking if there was a valve hit.

You're probably ok. It's the nature of these forums that we always speculate about the worst case

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Thanks, at least I can pull over if something goes bang, beats quiet glide.
I think I will just sit tight for now. Maybe pick up another motor at some point.

Now, onto next problem.
Thanks

Twinkieflyer said:

Thanks, at least I can pull over if something goes bang, beats quiet glide.
I think I will just sit tight for now. Maybe pick up another motor at some point.
Now, onto next problem.
Thanks

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Checking the tops of the lifters will take no more than 30 min. Time well spent...