2011 1.6 Diesel Golf starting issues

[winchman]

Has anyone had this issue?
Drives fine no fault codes or lights.
Leave it 12 hours and it starts but won't rev for a few seconds up to a minute like its struggling to breath / lack of fuel?
Its been in the garage twice he cant cure it, I have had a look and not sure what it is so any thoughts?

 

[8ob]

Sounds to me like its suffering a bit of fuel drainback, can be a bit of a sod to locate the fitting/pipe.

Bob

 

[winchman]

Sounds to me like its suffering a bit of fuel drainback, can be a bit of a sod to locate the fitting/pipe.

Bob

I did wonder I just cant find a garage I can trust to fix it they all want to change radom things.
Only good bloke I know is retired, he still works but its often weeks before he can look
I was going to do a service and see if anything changes?

 

[Melvyn Best]

Injector leak back test might be a good starting point?

 

[winchman]

Injector leak back test might be a good starting point?

How do I do that and what is it?

 

[Trevorleach]

Common rail has a common fault (geddit?) of injectors leaking back to much fuel causing starting issues.

 

[m_c]

My money would be on leaky/sticking injector(s), given injectors on that engine aren't exactly known for their robustness.

However I'd be starting with a live data check to get an idea of what's going on.
Low fuel rail pressure would be indicative of injectors sticking open causing excessive leak back, but combined with inconsistent cylinder balances, would point to injector(s) not doing what they're supposed to be doing.

Is the engine rough when it fails to rev?

 

[Melvyn Best]

How do I do that and what is it?

As others have suggested it could very well be leaking injectors causing the pressure to drop in the fuel rail when the engine is stationary. A leak off test is carried out using pipes that connect onto all of the injector leak off ports , the other end just goes into small jars the engine is then cranked over and the amount of fuel that “leaks off” is compared
Relatively cheap for a basic kit whereas the kit to get live data?

 

[winchman]

My money would be on leaky/sticking injector(s), given injectors on that engine aren't exactly known for their robustness.

However I'd be starting with a live data check to get an idea of what's going on.
Low fuel rail pressure would be indicative of injectors sticking open causing excessive leak back, but combined with inconsistent cylinder balances, would point to injector(s) not doing what they're supposed to be doing.

Is the engine rough when it fails to rev?

I think it feels a little rough

 

[indy4x]

@m_c so on a common rail diesel, is the fuel rail supposed to keep pressure when you switch off the engine?

I have a Jeep with the Merc OM642 engine, when the engine is shut off the fuel rail pressure drops significantly

 

[m_c]

@m_c so on a common rail diesel, is the fuel rail supposed to keep pressure when you switch off the engine?

I have a Jeep with the Merc OM642 engine, when the engine is shut off the fuel rail pressure drops significantly

Diesel common rails should dump all pressure as soon as the engine is stopped.

 

[winchman]

Small update
Took the old Chinese fuel filter out today
Fitted a £20 MANN one.
Wouldn't start, cranked it for ages.
Plugged it in showing low fuel rail pressure.

Checked in tank pump output by taking hose off filter loads of flow and pressure.
Tried the priming method of on and off 10 times as both pumps run briefly, when ignition is switched on.
Tried to start nothing
Eventually after several squirts of Easy start it ran.
So any ideas?
I am wondering about fuel rail pressure sensor I think it has two?
Or High pressure pump?
So any thoughts?