2014 MK6 Jetta Hard start after sitting. Please help.

[jackedshirt]

2014 Jetta TDI CJAA push start. 172000km. Still has DPF.

My apologies for a bit of long post, but I want to give everyone as much info as I can.

1. Recently had timing belt, pump and all timing hardware replaced. Top quality parts from GermanOEM. NEVER had this issue pre-belt change BUT I don't know if this is timing related or just coincidental.
2. Vehicle has tough time turning over after long sits overnight. After initial start, vehicle fires up just fine throughout the day.

Some background info:

- frost heater is always plugged in under -10celcius
-white power service is always put in every fill up generously
-I initially thought it could battery so it was replaced after i ran into this issue. Not the cause.
-oil or fuel filter were not changed at belt change however they were changed about 5000k ago.
-Glow plugs light up and off quick as they should when frostheater is plugged in
-I cycle plugs 2-3 in cold weather always

Symptoms:

After long sits overnight, if i cycle the glow plugs 2-3 times, i still get lots of healthy sounding cranking but no turn over until i either leave it cranking longer than usual or depress gas pedal. Once started, the fire up is very rough momentarily (sputters, chugs) and she will then get to idle. Dosent not stall nor do I find I have an power or performance loss after I get driving....After getting to proper idle, everything is back to normal. Its been quite cold here so I haven't been able to try it in warm weather, but as I mentioned, this is NEW issue. A couple plug cycles in deep cold weather and she would fire up no problem.

Mechanic said he initially had fuel pump timing off when he started car after belt change and after scanning via ODBEleven, it threw a a couple codes:
I cleared these codes to see if they were thrown as they were part of the belt mis timing, and they never came back.

-P0016 - Crankshaft Position-Camshaft Position Correlation Bank 1 Sensor A
-01314 - Engine control module (ECM) No signal/communication
Intermittent


Since depressing the pedal during the cold start helps the turnover, do you guys think it could be another fuel related issue? Ice in intercooler? (bottom grills have pipe insulating foam) I don't know if its a problem from the belt job since I don't have any other issues while driving or idling.

 

[ticaf]

Question is:has it ever started fine AFTER the timing belt job?

 

[jackedshirt]

Only starts fine if it hasnt been sitting overnight for a while. Is the timing still off?

 

[ticaf]

Probably not then. Maybe the timing belt job is truly coincidental.

On the mk7, the VVT device can loose oil pressure overnight and cause initial hard starting. Not sure if that applies to the mk6.

Hopefully someone here can help you.

 

[06bluebeetletdi]

Could it be frozen intercooler? Just wondering with the running rough after you start it. All you need to do is removed the intercooler hose on the passenger side and see if water comes out.

 

[taylomi]

You've maybe seen this thread already, but sounds like a similar issue: https://forums.tdiclub.com/index.php?threads/2015-golf-tdi-long-crank-first-start-of-the-day.481340/

 

[rhill2901]

I know the original poster probably has gone and left the community, but if after you have a timing belt replaced, you experience hard starts, it could be the timing belt alignment wasn't done properly. The original single piston pumps timing is very critical. Think about the situation of retarding or advancing the timing on a gas car and its effect on starting, same exact thing. Its not hard to check the timing. lower and upper covers removed, put a socket on the lower crank bolt and turn the engine by hand until the alignment mark on the crank aligns with the timing mark. (there are 2 posiitons this can occur, but only 1 is correct and the other is 180 degrees out). Take a phillips screwdriver, if you don't have the alignment jig kit (highly recommend every tdi owner have this set), and see if it will go into the holes in the cam pulley and the pump pulley. If it goes into one and not the other, then your alignment is off. You may need to slightly turn the crankshaft one way or another, SLIGHTLY not alot to get it to fit. If your screwdriver won't go in the hole, its too big, use a smaller diameter shaft. If neither line up, then turn the engine clockwise again until the crankshaft lines up again and check again. It doesn't hurt to check, and as long as you don't loosen the cam or pump pulley, you have not changed the alignment. My bet is the cam isn't aligned to the pump. Hope this helps someone out there.

You can save all of this headaches by upgrading your pump to the 3 piston variety and it maintains constant pressue on the fuel rail instead of requires being timed to the cam and crank.