Volkswagen Passat Forum banner

21 - 35 of 35 Posts

·
in dire need of an organic chemistry lesson
Joined
·
2,285 Posts
Have you checked the fuel injectors? Are they clean enough?
 

·
Registered
Joined
·
15 Posts
Discussion Starter #25
Since it's an easy job I would do it. Regardless if they are causing this it will be beneficial to the car.
Fairly straight forward? Do I need to purchase new seals or retaining clips? I do not believe they have ever been removed.
 

·
in dire need of an organic chemistry lesson
Joined
·
2,285 Posts
Fairly straight forward? Do I need to purchase new seals or retaining clips? I do not believe they have ever been removed.
Yes definitely new seals which are $4 at Autozone but clips are not needed as you can use the existing ones.
 

·
Registered
Joined
·
26,187 Posts
If you have a section of vacuum line, stick a bolt in the end. You can also buy vacuum plugs at most parts stores, in a pack with multiple sizes.
 

·
Registered
Joined
·
15 Posts
Discussion Starter #28
Not sure why I didn’t think of this earlier but.... I started the car shortly after running = no hesitation and starts normally. I then pulled off the brake booster line and let air in that portion of the vac system and tried to start it = no hesitation and started normally.

So I think I can eliminate that portion of the vac system.

The other portion under the intake manifold with three checks valves that also goes to the reservoir... does that take larger diameter hose? I don’t want to destroy the 1x use clamp and try only to find out it doesn’t fit and the old hose won’t seal
 

·
Registered
Joined
·
26,187 Posts
The hose to the coolant tank is larger, but I don't recall the size. It's closer to 1/4" ID and the hose is usually pretty stiff at the engine side. You can measure the plastic tube to get the size.
 

·
Registered
Joined
·
15 Posts
Discussion Starter #30
The hose to the coolant tank is larger, but I don't recall the size. It's closer to 1/4" ID and the hose is usually pretty stiff at the engine side. You can measure the plastic tube to get the size.
I am not trying to replace coolant lines. Just the vacuum lines below that.
 

·
Registered
Joined
·
26,187 Posts
Sorry, I meant the hose under the coolant tank.
 

·
Registered
Joined
·
30 Posts
"CTS appear to be working normally via VCDS. "
So what are the temperature reading when the engine is cold and not running?
These sensors are not expensive and you could plug a new one in without fully installing it to test the starting.

How is the fuel pressure and volume?

I have seen ignition switches cause strange starting behaviors but I would not think it would also cause a rough idle issue.

Good luck
 

·
Registered
Joined
·
271 Posts
I have seen ignition switches cause strange starting behaviors but I would not think it would also cause a rough idle issue.
That reminds me of an ignition issue I had with the car a decade ago. Basically it would not work in really cold weather and they replaced the ignition free. I'm not sure if it was a recall or not. I remember talking to the tech about it and he told me a workaround if it ever happened again was you start the car by waiting a few seconds (there was no number of seconds I watched him do it) at each point before the start point. I don't think it ever happened again though. It was a really long time ago so I don't really remember. It's a long shot but you could try that one morning.
 

·
Registered
Joined
·
15 Posts
Discussion Starter #34
"CTS appear to be working normally via VCDS. "
So what are the temperature reading when the engine is cold and not running?
These sensors are not expensive and you could plug a new one in without fully installing it to test the starting.

How is the fuel pressure and volume?

I have seen ignition switches cause strange starting behaviors but I would not think it would also cause a rough idle issue.

Good luck
I have not checked the CTS reading when cold. I will check that tomorrow.

I have not checked the fuel pressure or volume. I do not have a fuel pressure tester/gauge. Volume check by pulling the fuel rail and cranking with a container at each port?
 
21 - 35 of 35 Posts
Top