Source
r/tdi•
13804

Rough failure to start issue, thoughts?

My wife's 2014 TDI sportwagen has been having this issue since we bought the vehicle "new" in 2018 once it was released from the hold. A dealership is finally willing to do something about it and replaced the in-tank fuel pump a couple months ago but now the frequency of the issue has drastically increased, meaning whatever they did just made it worse.

I believe it is either air getting in the fuel line, or the high pressure fuel pump is not working when the failure happens. Prior to replacing the fuel pump, it was infrequent but concerning, almost always happening on a warm engine. Since the fuel pump has been replaced, it has been happening almost every time the vehicle is used and has now happened on a cold start after not being started for five days. Most often happens one to three times on the initial attempts, and if you let it sit for about five seconds it'll start up like nothing was ever wrong.

Anyone else ever have this issue?

https://reddit.com/link/13hd106/video/3pzswyaaxsza1/player

Posted May 14, 2023, 2:01 PM UTC

29
penpal69•

could be the starter going out.

2
Divisi0n•

I had this exact issue with mine, ended up being a bad battery. I replaced the lift pump, auxiliary pump, fuel filter, tried everything I could think of and it just ended up being the battery. It had tested as ‘ok’ but as soon as I replaced it, car started up faster and easier than it ever did. Even if your battery is “good”, replace it anyways and see what happens

1
13804OP•

The battery has already been replaced and had no influence on the issue or the frequency of it happening.

1
penpal69•

id check the starter since you already replaced all the fuel stuff and battery. even if there is air in the fuel system it would still turn over. you mentioned it started happening on a warm engine, a bad starter would start showing symptoms is when its hot.

1
13804OP•

The only fuel component that was replaced was the in-tank fuel pump. I'll mention the starter to the shop when I take it in next time.

And yes, it is almost always when the engine is warm, lately during a cold start but that was also when it was sitting out in the sun on a hot day so that could explain why if you're right.

1
Divisi0n•

Interesting, I had the same symptoms of it showing the issues during warm starts but never had an issue in the morning going to work after it had sat overnight.

1
rjz5400•

Vcds brosef. I dont know why anyone would own a modern car without diagnostic software...

Its so cheap, and so easy, and so capable. Vcds owner is 200$

Youtube full of how to's already. How many hours and dollars wasted already shotgunning parts?

Good luck

1
omegared138•

I have a long crank issue on my 2012 JSW, more common when the temperatures switches between cold and warm. Cold starts are never a problem, starts on warm mornings, is where it seems to struggle, like it's not getting fuel. Second crank it starts.

1
Intrepid-Ad6601•

2011 Jetta TDI sportswagen here. I have the same issue with start up. It will try to start and kill a couple times. Then on the fourth or fifth time it starts right up. It usually is an issue in warm weather.

I am wondering if it is a fuel pump issue or if it is a starter issue. I suppose it could also be the beginning of hydrolock from water in the intercooler hose - winter did just end in my area. Fuel filter, air filter, and battery are new.

1