Weird start problem cjaa

[zachattack]

Hey guys,

I redid the timing belt and water pump on my 2013 Jetta TDI using the guides here and got the car to start just fine. It would slowly crank then finally turn over, almost like the battery was low. Since the battery voltage was low and over 3 years old, I replaced it.

Now the car will crank fast, turn over then die immediately. If I try to restart it'll just crank and crank. If I turn the car off and try it again, it'll repeat that same pattern.

No CEL lights and when it ran, it ran well. I don't have any reason to believe it's out of time, but I could be wrong. I also don't have a VCDS setup but I'm looking at options for that. Any advice?

 

[Nathanael Greene]

It could be a corroded ground point, those can cause weird start problems. It's an easy thing to try, and at least eliminate one thing from the list of possibilities.

Nate

 

[zachattack]

I'm not seeing any loose grounds though I'm not sure where they all are. The ones I do see look good.

 

[JELLOWSUBMARINE]

I'm not seeing any loose grounds though I'm not sure where they all are. The ones I do see look good.

resistance is often internal like corrosion under the wire jacket. You may want to do a voltage drop test.

 

[Seatman]

Air in the fuel system? When I disconnected the fuel lines on my car to do the timing belt the fuel ran back to the tank a bit so created a problem. Of course vw decided having the pump prime with the ignition was to easy so did away with it.

Anyway I finally got it going properly but took a bit of doing. Didn't have the newer vcds at the time. Cars my first common rail tdi

 

[zachattack]

I was sure it was a fuel pump issue, but I hot wired the fuel pump under the rear seat and the one on the left side of the engine. Both pumps ran for 30 seconds or so a few times and that didn't help

 

[Nathanael Greene]

resistance is often internal like corrosion under the wire jacket. You may want to do a voltage drop test.

Exactly. They can look good, but have to much resistance.

Nate

 

[oilhammer]

OBD works... start there.

I don't think it wise to do a job as intense as a timing belt, without having some form of scan tool in your tool box. Even though in this case it is not specifically needed for this job, I just find it a bit cringe worthy from the outside looking in.

You could have botched the timing belt job, and now have a CMP/CKP correlation DTC, but you'd never know.

 

[zachattack]

I already mentioned there are no codes from an OBD2. I'm getting access to an obd11 today, hope that's enough to satisfy you
The car ran quite well but had a slow crank, like a low battery. Voltage on battery was around ten so it was changed but this did not help start the car, leading to the aforementioned problem. I'll post any further errors I find on the vag obd11 today.

 

[oilhammer]

Not me you have to satisfy. It's the car. Generic OBD2 stuff is next to useless.

And per your original post (copied below in case you missed) there was no mention of any use of OBD to check anything.

Hey guys,

I redid the timing belt and water pump on my 2013 Jetta TDI using the guides here and got the car to start just fine. It would slowly crank then finally turn over, almost like the battery was low. Since the battery voltage was low and over 3 years old, I replaced it.

Now the car will crank fast, turn over then die immediately. If I try to restart it'll just crank and crank. If I turn the car off and try it again, it'll repeat that same pattern.

No CEL lights and when it ran, it ran well. I don't have any reason to believe it's out of time, but I could be wrong. I also don't have a VCDS setup but I'm looking at options for that. Any advice?

 

[oilhammer]

"No CEL lights" doesn't tell you (or anyone) anything.

 

[zachattack]

You sound like an Internet neck beard but you're probably right. My harbor freight obd scanner doesn't show any cam/crank miscorrelation code (just the same EGR code I've had for years) but that probably doesn't mean the shafts aren't out of sync. I'll throw the car in the garage and pull it apart and check the timing again.

 

[oilhammer]

Well I'm not sure what an Internet neck beard is, but I do work on these cars every day and I'm just trying to help you (which is what you came here for... help).

Here's my "office":

And I've been balls-deep in more than a few CJAAs:

 

[JELLOWSUBMARINE]

Ya done stepped in a warm one dude. Best appologize

(@zackattack)

 

[Seatman]

Yeh sounds like a fuel thing but looks like youve

And I've been balls-deep in more than a few CJAAs:

I find it easier to use my hands

 

[lemoncurd]

Now the car will crank fast, turn over then die immediately. If I try to restart it'll just crank and crank. If I turn the car off and try it again, it'll repeat that same pattern

this is the EXACT behavior i had when i had an immobilizer issue

car would start, run for a couple seconds, then shut off. if you tried cranking again it would just crank and crank with no fire.

if you removed the key, you could try again, but it would result in the same immo shutdown. i didnt get any errors on the dash to my knowledge, but this was maybe 2 years ago so my memory may not be doing me justice.

do you by chance have a bedazzled circle which you place around the ignition key hole?
those are notorious for causing issues with the immobilizer.

like others have posted, grab a REAL OBD2 scanner. not what the dash says, or what your cheapy walmart generic obd2 reader say, OBD11 or VCDS. Post an autoscan or a read out of specific modules like ECU, TCU, ABS, cluster

 

[zachattack]

Sorry for the delay, but an update for posterity. Pulled the timing belt cover off and noticed the tensioner had slackened a bit. Ordered a new one and replaced it just in case it was bad. I also redid the timing and put it back together. Car started right up and drives great. I'm betting I didn't do the tensioner right but all appears well for now.
Thank all!

 

[oilhammer]

Thanks for reporting back. These timing belts have a few critically important steps, one of which is the proper tensioning with the nut loose enough to allow the eccentric to turn, but not too loose OR too tight to inhibit this motion, along with the crank locked and both the HPFP and cam sprockets free spinning with the shafts pinned. There is some nuance to do it correctly.

 

[Seatman]

Wasn't one of those new tensioners with no tab to lock into the engine?

That's what came in my new gates kit, have to rotate them anticlockwise to tension.