1.9 TDI rapider Leistungsverlust, starkes Nageln | Posts 32+

comco wrote:

The engine starts flawlessly, but the expected performance gain is absent, and the fuel injection still always begins at 27.9 degrees before top dead center. If the internal pressure of the VP is too low, then the new injection valve control piston may not be able to overcome the spring force, according to my understanding.

Therefore, in my opinion, approximately 28° vOT should be the early engagement point... ?
Then either the return spring has broken (possibly due to age), or the internal pressure of the pump is too high (-> possibly due to a blocked return line?), or the electric late-shift valve is not working.

Something doesn't quite fit .

Hello Ulf,

>Then either the return spring broke (presumably recently).

It was disassembled and is mechanically sound, with spring force intact. O.

>or the internal pressure of the pump is too high (-> possibly a blocked return line?),

The return flow is okay; I've already tested it. Unfortunately, I don't have a "pressure gauge" with the right fitting.
I'm considering making an adapter for the existing compression tester, but it can only handle a maximum pressure of 50 bar, while the VP internal pressure should be significantly higher.
What is the actual internal pressure of the VP at full load? 800 bar?

>or the electric late timing function is not working.

Hmm, I'd like to rule that out. SV is functioning correctly in all tests. The wiring harness has been checked, and there is NO change when 12 volts are applied to the SV during operation (using a cable extension and a 12V cigarette lighter adapter).



What if the VP's internal pressure is too low? In that case, the low pressure might not be sufficient to overcome the force of the return spring of the injection adjuster piston, meaning the piston would remain in its resting position, which is the maximum position. Early.
Another piece of evidence would be the low injection quantity.

Hi,
I'm sorry that the repair hasn't worked out yet. You still need to fully understand the function of the spray adjustment.

Quote:

to overcome the force of the return spring of the injection timing adjuster piston, therefore it remains in the resting position = maximum advance.

is incorrect. Idle state = late.
What surprises me is the observation:

Quote:

The SV also clicks audibly during the actuator diagnosis.

The fuel injection start-up procedure is checked with the engine running. You won't hear any clicking sounds!
Normally, the injection start control should be adjusted based on the difference between the extreme values (indicator = engine noise). I suspect something might be wrong with your diagnosis.
hg
Herbert.

Hi,

Ashes to ashes, dust to dust.

My mistake, I messed up the engine's direction of rotation .

What did you put together wrong there?
It's clear that you were thinking in the wrong direction, but what exactly went wrong for you? Did the subsidy start with the measuring device incorrectly configured?

Hello,

comco wrote:

Did you successfully replace the nozzle at that time, or did you just verschandeln it?

neither nor... I just took the next pump from the shelf and installed it . No, seriously, I had an engine failure the year before, and I only had to unscrew the pump from the old engine. I'll eventually take the broken pump to modify it into a swirl chamber pump, meaning I'll eventually attach the 10-bar high-pressure part of a VP37 to the pump from a 2-liter GTD. I'll put the MSW on the shelf, just in case . It might be useful sometime.

Best regards, Uli.

Herbert wrote:

The fuel injection start-up regulation is checked with the engine running. You won't hear anything click!

Hi,

I probably expressed myself poorly and was assuming we were talking about the diagnostic functions built into the MSG itself.

When the ignition is turned on, the SV (Solenoid Valve) actuates/opens approximately 5 times, and the camshaft of the MSW (Mechanical Speed Limiter) rotates about 30% of its possible range (from the rest position stop to the full travel stop) in a clockwise direction when viewed from above. The camshaft is free because the distributor has been removed.

@klahaui - I just had a misunderstanding about how the injection start adjustment, "pre-pressure," and high-pressure sections work, but the VP (presumably a component) is assembled correctly.

Today, I was just frustrated and decided to leave the car alone.

We'll continue on Friday.

Bye.

Jürgen.

Quote:

I probably expressed myself incorrectly and was assuming the actuator diagnosis was based on the MSG's own system: When the ignition is turned on, the SV (Solenoid Valve) actuates/opens approximately 5 times, and the camshaft of the MSW (Mechanical Switching Unit) rotates about 30% of its possible range (from the resting position stop to the full travel stop) in a clockwise direction when viewed from above. The camshaft is free because the distributor

has been removed. This has nothing to do with the injection start timing control or the actuator diagnosis.
Familiarize yourself with how it works before you start.
hg
Herbert.

Herbert wrote:

First, familiarize yourself with how it works before you start

.

Hi Herbert,

I will, of course, do that. .



The result of today: PERFORMANCE. Finally, it's running again.

The cause was the control valve.

Next week, once the new control valve is installed, the valve will be adjusted using VCDS. With the current, manually adjusted positioning, the part is working quite hard under full load.

Thank you very much.