FL1 TD4 warm start issues

Hi I'm having an problem with my FL1 TD4 it starts from cold no problem, but when it's hot it takes several goes to get it started, it appears to catch and then stall.

So far following info on this group I've done the following

- given it a good dose of injector cleaner
- replaced the fuel filter
- changed the camshaft sensor
- replaced the o ring seals on the hp fuel pump
- replaced 1 mismatched injector

Did a leak off test and this is when
I spotted what one of the injectors was the auto spec and the other 3 where l were manual, I've swapped this over so now all are the manual spec injector

I was concerned that this would at the very least confuse diagnostic results, but understand that it isn't critical to have auto or manual and long as they are all the same

(I had the replacement injector tested professionally so pretty confident that is ok)


Have leak off test and and have some live diagnostics (see attached)

Live diagnostics from a typical failed start below suggest rail pressure is ok I think?

If anything it looks like 2 & 4 are leaking more than 1 & 3 but this isn't excessive is it?

Appreciate any thoughts before I start replacing more injectors.

I'm assuming that since I'm getting sensible rail pressure readings that it's not a rail pressure sensor fault

Thanks in advance

Leak off test is 1 minute at idle with warm engine

The camshaft position sensor you changed is new and recent?
One on the way out can give poor starting when warm.

Freddie17 said:

The camshaft position sensor you changed is new and recent?
One on the way out can give poor starting when warm.

Click to expand...

Brand new, recent (after this problem first developed). NGK branded OEM part.

Dave foobar said:

Hi I'm having an problem with my FL1 TD4 it starts from cold no problem, but when it's hot it takes several goes to get it started, it appears to catch and then stall.

So far following info on this group I've done the following

- given it a good dose of injector cleaner
- replaced the fuel filter
- changed the camshaft sensor
- replaced the o ring seals on the hp fuel pump
- replaced 1 mismatched injector

Did a leak off test and this is when
I spotted what one of the injectors was the auto spec and the other 3 where l were manual, I've swapped this over so now all are the manual spec injector

I was concerned that this would at the very least confuse diagnostic results, but understand that it isn't critical to have auto or manual and long as they are all the same

(I had the replacement injector tested professionally so pretty confident that is ok)


Have leak off test and and have some live diagnostics (see attached)

Live diagnostics from a typical failed start below suggest rail pressure is ok I think?

If anything it looks like 2 & 4 are leaking more than 1 & 3 but this isn't excessive is it?

Appreciate any thoughts before I start replacing more injectors.

I'm assuming that since I'm getting sensible rail pressure readings that it's not a rail pressure sensor fault

Thanks in advance
View attachment 321943View attachment 321938
Leak off test is 1 minute at idle with warm engine

Click to expand...

I always do the leak back test over 2mins and you are looking for no more than 20ml in that time.

In this test it was conclusive.
1

You 1min test shows 10ml 20ml 10ml 20ml each long line represents 5ml
2

Therefore if you ran the test for 2mins. you should have the readings of.
20ml 40ml 20ml 40ml making this makes 2/4 outside the limit so need looking at.

This is how we found out below back in 2022, we all had been reading the leak back test cylinders wrong.