[Solved] VW Passat b5 1.8 8v Gasoline - Cold Engine Jerking at 2k RPM, Post NGK Wires & Candles Update

Hello.
I have a VW Passat b5 1.8 8v. Gasoline without gas. For some time the car after firing and starting jerks at revolutions from 2 thousand. After driving 1-2 km after jerking there is no trace. The engine catches some temperature. The car tugs only when the engine is cold. First, I replaced the candles and wires. There is no error on the computer, e.g. Loss of ignition. And now the question is where to start? The new coil is about 800 PLN and I do not want to start with THIS while the wires and candles are from NGK. And after their exchange there is a big improvement but not total. On the other hand, cold starting of the engine is exemplary, the same is the engine's cold operation at idle. In the first gear, he also starts without any problems. The problem arises from the second gear of 2 thousand revolutions as I wrote. Has anyone met this before? Where to start?
Regards

Maksiu922 wrote:

The new coil is about PLN 800 and I don't want to start with THIS

Remove the coil, heat for 2-3 hours in an "oven" at 60-70 degrees.
Mount it to the "cold" car and check that there are exactly the same symptoms that you described above.

Or heat the coil with a heat gun at 100C taking care of the wires, you will save time with disassembly.

CameR wrote:

Maksiu922 wrote:

The new coil is about PLN 800 and I don't want to start with THIS

Remove the coil, heat for 2-3 hours in an "oven" at 60-70 degrees.
Mount it to the "cold" car and check that there are exactly the same symptoms that you described above.

I did so too. I warmed the coil for 3 hours and after the assembly there was no difference.

Maksiu922 wrote:

there was no difference

... i.e. rather it is not a coil or at least there are no microcracks through which moisture penetrates and causes HV micro breakthroughs.

Hello!
And maybe you have something like that you start the car in the morning, go and at the beginning everything is OK and only after about 1-2 kilometers this circus begins?

However, I would focus on wires and candles. Just because they're new doesn't mean they can't be of poor quality. This one. Second - there are three unpleasant ailments - the throttle module integrated with the adjuster and TPS sensor, the camshaft adjuster cylinder and the pneumatic suction valve. The first two, as a rule, generate errors in the event of a fault, while in the case of the 3rd element, sometimes you hear a hissing sound near the throttle - the engine sucks "left" air.

It is similar in our case, as soon as it fires up it moves for a dozen or so seconds so that it is impossible to drive. But in my case I sniffed the fuel leak, maybe the hose snapped (and the fuel system is aerated). Everything as the author described, fires up and works on a sterile pattern.

Fire it in the morning, ride it until it stops pulling, even if it doesn't get hot, put it out. Fire it a minimum in 2-4 hours so that you can be sure that it is cold, before starting a minimum turn the key twice as if you were warming the candles (you start the fuel pump twice), start it and write if it goes on.

ven0n wrote:

Fire it in the morning, ride it until it stops pulling, even if it doesn't get hot, put it out. Fire it a minimum in 2-4 hours so that you can be sure that it is cold, before starting a minimum turn the key twice as if you were warming the candles (you start the fuel pump twice), start it and write if it goes on.

I'll do it anyway. I also decided to replace the fuel filter, but that's after the hose test. If water has accumulated in the fuel filter, it may freeze and hinder fuel flow. However, there is such a thing as the return of fuel from the engine (someone mentioned it to me). Perhaps the fuel heated after returning to the tank from the engine when it goes to the filter heats it enough that the water that is frozen there heats up and melts. Then the correct fuel flow occurs.
And where did you have the damaged hose? Perhaps this is a characteristic fault?

Added after 3 [minutes]:

misterbociek wrote:

Hello!
And maybe you have something like that you start the car in the morning, go and at the beginning everything is OK and only after about 1-2 kilometers this circus begins?

No, the problem arises as soon as it changes gear from 1st to 2nd. And with these frosts (-10 degrees) I have to drive from 4 or 5km for improvement

Added after 2 [minutes]:

robokop wrote:

while for the 3rd element, sometimes the throttle hiss is heard - the engine sucks the "left" air.

Tomorrow I will check if something is heard, and by the way, is it a fairly clear hiss? Do you have to listen to hear it?

Maksiu922 wrote:

And where did you have the damaged hose?

I have not done it yet, cold, no garage and the engine with accessories fills the space under the hood to the brim, I only know that you feel gasoline, the car used every day drives normally.

Maksiu922 wrote:

Tomorrow I will check if something is heard, and by the way, is it a fairly clear hiss? Do you have to listen to hear it?

As the hose shot specifically, the hiss should be clear, for me it burst from the vacuum of the brake servo (058 133 783 L) at the bend, I already heard it standing even a meter from the car (quiet engine) but still did not jerk.
Look for the hissing on the right rear of the engine from the perspective of the car opposite, just put your ear where there are the most snakes.

Maksiu922 wrote:

ven0n wrote:

Fire it in the morning, ride it until it stops pulling, even if it doesn't get hot, put it out. Fire it a minimum in 2-4 hours so that you can be sure that it is cold, before starting a minimum turn the key twice as if you were warming the candles (you start the fuel pump twice), start it and write if it goes on.

I'll do it anyway. I also decided to replace the fuel filter, but that's after the hose test. If water has accumulated in the fuel filter, it may freeze and hinder fuel flow. However, there is such a thing as the return of fuel from the engine (someone mentioned it to me). Perhaps the fuel heated after returning to the tank from the engine when it goes to the filter heats it enough that the water that is frozen there heats up and melts. Then the correct fuel flow occurs.

So I did the test. I drove quite a lot until 2pm today. The car stood up to 18 hours. I fired as you wrote (I turned the key twice). I made it less than 6 km. Interestingly, the first 1.5 to 2km jerked nothing. What was the worst driving period so far. The car was driving properly. At 2 km, delicate single jerks appeared. They appeared up to 4 km with decreasing quantity and power. That the symptoms would disappear completely.
The conclusion I have is a problem with the fuel supply. Unfortunately, I also do not have a garage and the frost is strong so I will change the filter only when the temperature is above 0. And tomorrow I will buy a means for draining water from the fuel system. I will write how it all ends in a while. Is this enough or is it necessary to look for leaks in the system? Regards

So now before you turn it on again, turn the key 4 times, when you turn the key to the off position, wait 5-10 seconds, to be sure pull it out so that there is a greater chance that the information in the computer that will turn the pump will reset. Then you'll have even more confidence that it's something with the fuel system. If you will drive correctly from the very beginning and then start jerking again, you can assume that the pressure generated by the fuel pump drops, or the water collapses around the system.

Today I added a means to remove water in the fuel system and tomorrow again before 7 am departure. I did today with about 7km after adding, so it will certainly spread along with the fuel. Tomorrow morning I will see if there is improvement. I'll let you know ...

Unfortunately, it is still jerking. But I won't do anything else during freezing weather

It tugs immediately after firing despite using the method I proposed?
Does it start jerking while driving 2km further?

Immediately. Today is a lot of warm so jerking is almost gone. It was raining again and the high humidity does not affect the quality of the engine. Maybe replace the fuel filter soon

I was able to change the fuel filter before winter came again. Temperature around minus 5 or even minus 7 degrees. There is no trace of jerking on the new filter. It is true that on that filter I made almost 15 thousand km and so it was to be replaced. Regards and thank you for helping me get started