Cold weather, engine runing rough

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Le_Combattant
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Re: Cold weather, engine runing rough

Post by Le_Combattant »

JiSingh1 wrote: Mon Jan 26, 2026 9:53 am
Le_Combattant wrote: Mon Jan 26, 2026 6:22 am Well, it's the only issue I have so far.

For an 11 years old car, sleeping outside all the year with 201800 km on the clock, it's not that bad I think ^^
Fair enough!

I remember we spoke about gearbox oil a few years ago, trying to look at what was best :D
Never ended up doing mine.

Currently battling with stop start errors, heavy steering, air con pressure problems, air con energy reduction fault, whistling on acceleration and just horrible suspension on mine :shock:
Aah yeah, now I remember.
For the gearbox oil, I finally bought the OEM one from VW. She is now dead smooth. An oil change is scheduled this year.

Start and stop error, multiples possibilities. You have a scan tool ?

For the whistling on acceleration, what kind of engine do you have ?
JiSingh1
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Re: Cold weather, engine runing rough

Post by JiSingh1 »

Le_Combattant wrote: Mon Jan 26, 2026 6:22 am Aah yeah, now I remember.
For the gearbox oil, I finally bought the OEM one from VW. She is now dead smooth. An oil change is scheduled this year.

Start and stop error, multiples possibilities. You have a scan tool ?

For the whistling on acceleration, what kind of engine do you have ?

Never did my gearbox oil - although you did point me towards the MTF5300 I believe, just been debating if it's worth the £100 or so.

Yes I scanned it - it's related to a U141100 code from what I can tell across forums, drive.ru had some good posts but the fixes range from a blown fuse, replacing the positive terminal cable, replacing the negative cable, changing the ground cables, software updates and more :shock:

Also got a B10ABF0, debating whether to change compressor, or start with the pressure sensor or just get a refill done... yeah my polo isn't very happy!

It's a 1.0 TSI CHZC. Very mild whistling you can only hear with no music and stuff so I just do that :lol:
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Le_Combattant
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Re: Cold weather, engine runing rough

Post by Le_Combattant »

JiSingh1 wrote: Mon Jan 26, 2026 1:05 pm
Le_Combattant wrote: Mon Jan 26, 2026 6:22 am Aah yeah, now I remember.
For the gearbox oil, I finally bought the OEM one from VW. She is now dead smooth. An oil change is scheduled this year.

Start and stop error, multiples possibilities. You have a scan tool ?

For the whistling on acceleration, what kind of engine do you have ?

Never did my gearbox oil - although you did point me towards the MTF5300 I believe, just been debating if it's worth the £100 or so.

Yes I scanned it - it's related to a U141100 code from what I can tell across forums, drive.ru had some good posts but the fixes range from a blown fuse, replacing the positive terminal cable, replacing the negative cable, changing the ground cables, software updates and more :shock:

Also got a B10ABF0, debating whether to change compressor, or start with the pressure sensor or just get a refill done... yeah my polo isn't very happy!

It's a 1.0 TSI CHZC. Very mild whistling you can only hear with no music and stuff so I just do that :lol:
I founded few weels ago, the exact same oil for our gearbox. Of course VW is not an oil manufacturer and the shape of the bottle is from Shell.
By comparing the datasheet, I founded it
It's the Shell Spirax S5 MTF X 75W.

Hmmm not a quite funny troubleshoot. I'm touching wood with my A/C. Never hasd a single issue. Just a maintenance few years back with oil/refrigirant replacement. As she's running everyday, it may help to maintain the system in good condition.

Do you have a picture of your engine bay ? On the left side, near fuel/evap suppley lines ?
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Le_Combattant
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Re: Cold weather, engine runing rough

Post by Le_Combattant »

So I managed to make my "brand new" pump running with direct connection with my battery removed from the car.

Not the best plan in term of safety but, It worked :lol:
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Short video:
https://youtube.com/shorts/Ne2hkL8yxAs?feature=share

Pump is running smooth and without any special noise. I hope it will solves my issue...
If the weather is no too rainy tomorrow, I will replace it.
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Le_Combattant
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Re: Cold weather, engine runing rough

Post by Le_Combattant »

So finally, the fuel pump is replaced (temporally).

The dismantling went smoothly. I had taken care not to fill the tank to avoid any unpleasant surprises.
With the tool, the ring came loose without any difficulty.
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No comment on the condition of the filter...
The bottom was covered in brown particles in some places. Like powder or dirt.
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For the bottom of the tank, very slight deposit just below the pump:
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Reassembly was a bit more difficult.
The new seal, even though lubricated with fuel, was very difficult to insert.

But once in place, I was able to reassemble the clamping ring, albeit with some difficulty.
This little battle caused some damage to the fuel hose:
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The metal plate around the opening is not rounded, but rough and slightly sharp.
When the clamping ring was fitted, the fuel hose came into contact with this metal plate, causing this mark.
It's not deep, but I would have preferred to avoid it happening.

Replacing it is not particularly complicated. Without removing the rear suspension, you would simply need to ‘loosen’ the tank fasteners to obtain sufficient clearance.
To be continued.
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Pressurisation: no leaks, no fuel smell
I went straight to the petrol station to fill up.

After a few kilometers, I can already report that the car is more pleasant to drive. More torque, more power.

The installation is only temporary; I still need to swap the fuel gauges. Unfortunately, I didn't have the tool to remove the pins from the three cables to do the swap.

As for the bottom of the tank, do you have any recommendations for removing this deposit, if possible?
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Le_Combattant
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Re: Cold weather, engine runing rough

Post by Le_Combattant »

So finally, the LPFP replacement is done.

Last week I installed temporally the "new low mileage" pump in the fuel tank to test it. The car runs good, seems to have more torque but still lack of power on a specific hill.

So yeah, temporally because of two things

-Cleaning of the bottom of the fuel tank
-Fuel gauge sender swapp

I take care about those steps yesterday:
Cleaning was straight forward. I was expecting more dirt:
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But now, it's looks perfect.

Next step was the fuel gauge sender module swapp. Since the one I received was slightly bended, I prefered to take the one from my original fuel pump.
Simple as hell: You have to push on each terminals two clips side to side and pull the cable outs.
Color codes make things easier.
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And now, we have a hybride, almost brand new fuel pump:
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Back in the fuel tank:
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Because it was late and night was already there, I waited until today to perform installation test.
Put 20 liters of fresh fuel and....
mr-bean-fuck-you.gif
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*My car to me*

The car started but...the fuel gauge did not move...even with the fuel tank half full.
What the hell !

I took the car to perform a road test and see if something was wrong (of course something was).
But cables location were not mixed, I took many pictures. And with color codes, it's impossible to make mistake.

So again, I removed the fuel pump and I saw that the floatting part was stuck (?) From what, I didn't know. After making sure it was moving freely, I installed everything back and start again.

Hura ! Now everything work.
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ciclo
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Re: Cold weather, engine runing rough

Post by ciclo »

Congratulations!💪😎
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Le_Combattant
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Re: Cold weather, engine runing rough

Post by Le_Combattant »

ciclo wrote: Tue Feb 10, 2026 5:45 pm Congratulations!💪😎
Thank you.
This weekend temp will drop to reach -2/-3. It will be a nice weather to see how the engine handle.
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Le_Combattant
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Re: Cold weather, engine runing rough

Post by Le_Combattant »

So without any surprise, hesistations are still present.

f**k, I don't know what to do now.

Oxygen sensor ?
Fuel injector ?
Charcoal filter ?

....
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