Injector issues (avf)

passat2004

New member
Joined
Mar 20, 2017
Location
Norway
TDI
2004 Passat 1.9tdi 130hp 4motion
Hi. I have a 2004 Passat with the AVF engine. 130hp tdi pumpeduse.

Two years ago, i swapped the camshaft,lifters and bearings. Had excessive wear to several lobes, and one holed lifter.
The new lifters was the black reinforced ones, but the camshaft was clearly redone.

Now one day i had a sudden loud ticking noise from one cylinder, and suddenly the car didn't rev up at all.
It seemed the "flap" in the anti shudder valve had come loose, and was blocking the intake.
Removed the flap, and the car was drivable again. But the ticking noise was still there.

The car drives fine when cold, but then it goes in limp mode. It shudderes at about 3400 rpm, 2nd and 3rd gear.
I get the code: P1557 - Charge pressure control Positive deviation.

I measured the injector values in block 13, and it seemed like the values on cylinder 2 was stuck at 2.99.
So i checked the connectors on injector loom, and tried swapping injector 1 and 2, still the same.
I then swapped all 4 injectors with a used set from another car, but still the same.

After some driving, the ticking noise went away, but injector values stayed the same.

Typical values at idle:

Cyl 1: -0.26 mg/h
Cyl 2: 2.99 mg/h
Cyl 3: -1.08 mg/h
Cyl 4: -1.81 mg/h

When holding about 1500rpm, the first 3 cylinders gets fairly even.

I fear the 2 small screws holding the "flap", have gone in the engine and damaged something. But wouldn't the car smoke more then ?

I don't have the equipment to do a cylinder compression test.

So far i have:
- Swapped all injectors from another car
- Did the injector lash adjustement.
- Emptied diesel filter, to check if it had oil in it.
- Checked cam lobes/lifters - Hard to see without taking the camshaft out.
- Disassembled the intake manifold, and tried my best to clean it, and in the head.
- Cleaned n75, map sensor, maf sensor.
- Tightened connectors on injector loom, and measured cable continuity.

What is the next step? I don't want to use much money on this engine, but if this points clearly to a worn injector loom/harness, i could go with that.
 

ebeday

Active member
Joined
Jun 19, 2009
Location
canada
TDI
2003 jetta TDI 2015 jetta TDI
Engine problems

I read your post today. I don't have alot of experience with the pumpduze engines but have lots of experience with other electronic controlled engines, ( Caterpillar)
The ticking noise is undoubtedly from ingesting the screws from the antishudder flap screws. My guess as to why the engine has no other damage is that one or both screws have imbedded themselves in the top of a piston. The imbedded screw is protruding enough that it or they strike the cylinder head at the top of piston stroke.
The DTC code is to do with excess manifold boost,, it is possible that one of the screws jammed the vanes in the VNT turbocharger, as it exited the turbocharger.
The code is VW speak for a pressure than is more than normal (positive). My 03 has plagued me with this issue for a long time but in your case there may be a cause, jammed VNT vanes.
I am sure the injector values being read are what the computer determines as the amount each injector is contributing as the engine runs. I don't have experience on this particular engine to make a comment, other than to say that this is probably normal. The fact that even with different injectors, the values stayed the same would tell me that the values are programmed into the ecm, having to do with dynamics of the engine.
 

passat2004

New member
Joined
Mar 20, 2017
Location
Norway
TDI
2004 Passat 1.9tdi 130hp 4motion
Thank you for answering :)

That does make sense.

6 months ago, i got the ticking noise, but it went away the same day.
Now i got the noise again, but went away after some intensive driving.
It seems logical that the first screw loosened 6 months ago, and the other one now.

I'm tempted to split the turbo and give it a good clean, checking for screws at the same time.

The injector values shouldn't vary much more than 0.5 between each injector, so they are way off.

I just hope the screws haven't contributed to poor compression in one of the cylinders though. I understand that the injector readings can get out of range, if one or more cylinders loose compression. The ecu tries to compensate for poor compression, by injecting more/less fuel into that cylinder. At least i think it does.

Will check turbo, and order the injector loom tomorrow !
 

passat2004

New member
Joined
Mar 20, 2017
Location
Norway
TDI
2004 Passat 1.9tdi 130hp 4motion
So i checked the turbo, and it was shot.
The impellar on exhaust side was missing small pieces, and some of the vanes was slightly bent.

Swapped the turbo for another used one, and got the car up and running again :)
I actually had to adjust the stop screw under the actuator on the "new" turbo, to get it running about right.

The injector values is still the same, even when i replaced the injector loom.
But for all i know, they could have been that way for a long time. I do suspect the remade camshaft is part of that issue.

But anyway, thank you for helping!
 
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