Poor acceleration & Misfire & High fuel consumption

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fmatyas97
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Posts: 1
Joined: Sun Feb 07, 2021 8:11 am
Drives: VW Polo III 6n2 1.4 44kW (AUD)
Location: Hungary

Poor acceleration & Misfire & High fuel consumption

Post by fmatyas97 »

Hi!

I have a VW Polo III 1.4 44kw (AUD engine code).

My problem is: My polo was weak, and the acceleration was poor. A week ago i got two fault code: The lambda probe, and it's heating was gone. So a bought a new Bosch probe, and it was great for 1-2 day. Then, on a morning when a started the car only 3 cylinder worked, and after a few revolution it worked normally, but I heard it wasnt smooth, and the car just began weak again. I got these fault codes: 16684 16687 (Multiple misfire, and misfire in the 3rd cylinder) Yesterday it started perfectly, and the car was just perfect. The engine was smooth, and quiet, and it was strong, with every cylinder. What can be the problem?

In the last few month i replaced these:
lambda probe (front of cat)
Ignition coil
ignition cables
throttle body
battery


The car was weak in the last 3-4 month, and the engine didn't ran smooth.
There is a leak in the exhaust system (flexi pipe).
You can smell a little gasoline around the car while running.
I only use premium gasoline.
The camshaft position sensor can be wrong (When i plugged out, i got the fault code, but the engine worked the same way.)
The sparks was replaced 25.000 km ago.
Oil was replaced last summer, with the air, and oil filters.
I drive about 40 km daily (2x20), and i don't use in city. Mainly I'm driving like a grandpa (shifting gears when reaching 2000 RPM, and my max speed is 85km/h), but sometimes drive on high revs, so my car doesn't get too lazy
And no matter what i do, my fuel consumption can't got under 7 liter. When I bought it it was 5.2 liter/100 km

So, what should I replace next time?
Johntheo1
Bronze Member
Posts: 138
Joined: Mon Jan 11, 2021 8:52 am
Drives: 2018 MK10 AW1
Location: Cork

Re: Poor acceleration & Misfire & High fuel consumption

Post by Johntheo1 »

Maybe a compression test in case of (hopefully not) valve problem.
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