Cold misfire cyl #1

[jasantos40]

Greets


I've been having some trouble with my tdi pd150.
On cold starts I get misfires for the first 5 seconds, with white smoke, and injector #1 reading starting at 2.99, and slowly droping, 10 secs after the engine is fine, the other injectors are ok, just negative compensating the first injector,


When warm I get all the injectores between -0.12 and 0.12, due to new camshaft and lifters. While warm is perfect. Pulls ok, mpg is ok.


Oil level doesnt move.


Have clear lines at the fuel filter, no oil on fuel.


I have a video with inj values but I can't share it. I'll give you the numbers since the engine is turned on, after sitting for +8 hours at 17°C, the values appear every second since startup, from 1 to 4 cyl has vcds shows:
2.99 -1.41 -1.15 -0.59
2.99 -1.29 -1.29 -0.52
2.99 -1.27 -1.36 -0.47
2.96 -1.18 -1.41 -0.40
2.80 -1.08 -1.46 -0.21
2.61 -1.04 -1.48 -0.07
2.40 -0.94 -1.44 0.00
2.16 -0.87 -1.36 0.02
1.93 -0.80 -1.29 0.09




And after some minutes:
-0.02 -0.12 0.00 0.12






On a compression test, cold readings, I get:


#1 28.5bar
#2 33bar
#3 30bar
#4 32bar
#1 27bar


Hot:


#1 29bar
#2 33bar
#3 31bar
#4 32bar
#1 30bar


Yesterday I swap Injector #1 and #2 to check if the inj deviation moves, also swapped the wiring loom.


Today, 20°C, I start the day with these values:


2.61 -1.20 -1.01 -0.38
2.64 -1.18 -1.13 -0.35
2.49 -1.06 -1.18 -0.24
2.38 -0.99 -1.25 -0.16
2.31 -0.85 -1.29 -0.12
2.14 -0.78 -1.34 -0.05
1.95 -0.66 -1.32 0.00
1.72 -0.59 -1.27 0.14
1.58 -0.52 -1.27 0.16


No injector or seal problem.


Any more ideas for diagnostics before pulling the head? Or should I do the leak down test before?


Camshaft and lifters also new, had a broken lifter a #4, that's solved. Glow plugs swapped also.

[jasantos40]

Here's a video how it starts.


https://www.youtube.com/watch?v=oGiKLZH-KfQ


VCDS, this time, was quicker to show me values. Funny that it starts with:


0.45 -0.24 -0.07 -0.21


Then it gets all messed up.

[Crasher]

VCDS says +/-2.99 as a maximum but in my experience anything even approaching +/- 1 indicates an issue. You can see there that number 3 is fighting against number 1 to keep things smooth, keep in mind the 1 3 4 2 firing order. With the way it changes with temperature, the first thing I would do is change the head harness but over the last 13 odd years I have replaced a disproportionate number of ARL injectors compared to the ASZ which is puzzling as they are the same.

[jasantos40]

VCDS says +/-2.99 as a maximum but in my experience anything even approaching +/- 1 indicates an issue. You can see there that number 3 is fighting against number 1 to keep things smooth, keep in mind the 1 3 4 2 firing order. With the way it changes with temperature, the first thing I would do is change the head harness but over the last 13 odd years I have replaced a disproportionate number of ARL injectors compared to the ASZ which is puzzling as they are the same.

Hi, thanks for the reply.

Injector harness already swapped, same numbers.

Is it time to pull the head off? Since cyl #1 has the biggest fuel compensation and also the lowest compression? Or could it be just a coincidence?

[Crasher]

You say it has had a new cam and lifters but what about the arms and were they reset to the new cam? Be warned about taking off a PD head, the term can of worms being opened doesn't do it justice, you could easily get yourself into a £3k parts bill without blinking.

[jasantos40]

You say it has had a new cam and lifters but what about the arms and were they reset to the new cam? Be warned about taking off a PD head, the term can of worms being opened doesn't do it justice, you could easily get yourself into a £3k parts bill without blinking.

Yes, arms were reset.

All the job is done by me, so no money for labour. Has I suspected, the rod on the cyl #1 has scoliosis. I'm looking at about 250€ tops on parts.

All TTY Bolts, Headgasket, bearings, rings for all pistons, and somethings I might be forgetting.

Pistons not in order:

[Crasher]

Ahh, Banana rod....