Breaking up and misfiring

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magalinn
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Breaking up and misfiring

Post by magalinn »

I have a 1.9 tdi Seat cupra, car has stock software and straight pipe only and noticed that when the car is cold and i accelerate it sounds like limmiter at around 3k rpm.) up and misfires and when i change gear the turbo dumping noise is louder than normal from the exhaust And if i continue to drive it a little hard and it warms up then the power is back and boost is normal.



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panic-mechanic
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Re: Breaking up and misfiring

Post by panic-mechanic »

Why are you driving a cold engine hard?
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Re: Breaking up and misfiring

Post by Unobeat »

Eish
Poor car, don't drive a cold engine hard as it is still warming up.
THANAS wrote:Mix them together to create Shellstrol, and then mix that with Winstrol to create the ultimate, maximum performance oil for your engine.
panic-mechanic wrote:When I build engines and do stuff like this I do it when there is nobody else around, No distractions, No phone nothing so that you don't forget what you should be doing. It's the little things that make them run right. Anybody can slap a basic bottom end together. that is the easy bit. It's all the little things that makes these builds a success or not.
magalinn
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Re: Breaking up and misfiring

Post by magalinn »

The temp is around 60 or 70 so its warm enough to pull to around 3000rpm I'm sure.

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panic-mechanic
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Re: Breaking up and misfiring

Post by panic-mechanic »

Scan, look at water temp and if it seems reasonable in the reading blocks, then look at injector deviation and see if it is in limits.
Can be caused by an iffy injector.
Your story has now changed as you said it does it when cold but not hot.
Stephan van Tonder - Jhb - Putfontein Benoni
'05 Audi A6 3.0L TDI Avant
'09 Touareg 3l TDI
'13 VW CC 2l tdi (repair project)
'05 Touareg v10

Perfect Power dealer. I do dyno tuning.
magalinn
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Re: Breaking up and misfiring

Post by magalinn »

Ok i will check injectors and water temp. I noticed twice when it was cold and then i left the car to warm up to 70 or less and it still had the same problem. Sorry i did not explain properly at 1st.

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Re: Breaking up and misfiring

Post by magalinn »

Checked this on idle with vcds does the maf part look right and the idle speed runningImage

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panic-mechanic
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Re: Breaking up and misfiring

Post by panic-mechanic »

Nope, that maf reading looks way high. Ws the car still cold because 38 deg temp is not a engine at operating temp. Injector deviation looks fine.
Stephan van Tonder - Jhb - Putfontein Benoni
'05 Audi A6 3.0L TDI Avant
'09 Touareg 3l TDI
'13 VW CC 2l tdi (repair project)
'05 Touareg v10

Perfect Power dealer. I do dyno tuning.
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Re: Breaking up and misfiring

Post by THANAS »

MAF reading looks correct, that's mg/stroke. 1900cc should pull around 475 (1900/4) mg/s at idle at the coast so 460 is ballpark for altitude.
magalinn
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Re: Breaking up and misfiring

Post by magalinn »

THANAS wrote:MAF reading looks correct, that's mg/stroke. 1900cc should pull around 475 (1900/4) mg/s at idle at the coast so 460 is ballpark for altitude.
Thanks for the repose.


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Re: Breaking up and misfiring

Post by panic-mechanic »

Ah carp I didn't read the tag.. Looked at the 850 :oops: :bang: old age is cathing up now..
Stephan van Tonder - Jhb - Putfontein Benoni
'05 Audi A6 3.0L TDI Avant
'09 Touareg 3l TDI
'13 VW CC 2l tdi (repair project)
'05 Touareg v10

Perfect Power dealer. I do dyno tuning.
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Re: Breaking up and misfiring

Post by magalinn »

So the 850 is correct

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Re: Breaking up and misfiring

Post by magalinn »

So the 850bis correct and when i drivevthe actual should reach the specified maf of 850?

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