gregg
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Every day is a school day.
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Post by gregg on Feb 19, 2019 18:24:55 GMT 1
Im using this on my phone so doesnt show up, will try on laptop once i get home
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gregg
New Member
Every day is a school day.
Posts: 72
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Post by gregg on Feb 19, 2019 18:29:53 GMT 1
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gregg
New Member
Every day is a school day.
Posts: 72
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Post by gregg on Feb 19, 2019 18:30:48 GMT 1
My other pictures are too big to load on, thays the smallest. I'll try and sort it later on and get rest uploaded
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Post by valhalla on Feb 20, 2019 0:17:30 GMT 1
I don't believe any of the data coming off your MAF meter. Either VCDS has the wrong configuration file here, or your meter is duff.
An air intake temperature of 114celcius at this time of the year is stretching the point, unless you have a massive draw of air from underbonnet instead of external to the car. In which case, fix that first, before you try anything else, otherwise you will be wasting your time - check the ducting into the air-filter box is intact and not come adrift from the box.
The MAF reading of over 1200mg/stroke is silly - it just doesn't happen. 800mg/stroke is good, 1000mg/stroke is very good......
EDIT: To confirm your MAF meter readings, see if you can take a reading off the car after a run, let it idle for more than a minute, then get a VCDS snapshot. You should be seeing somewhere around 450mg/stroke on a modern 2.0litre 4-pot, maybe 480mg/stroke if there is any residual boosting from the turbo, but much more than that would suggest a duff meter.
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Deleted
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Post by Deleted on Feb 20, 2019 1:09:40 GMT 1
Ah I see it now, he has the Turbo exhaust turbine connected to the air intake which is why the temperature is so high   |
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gregg
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Every day is a school day.
Posts: 72
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Post by gregg on Feb 20, 2019 1:48:25 GMT 1
I don't believe any of the data coming off your MAF meter. Either VCDS has the wrong configuration file here, or your meter is duff.
An air intake temperature of 114celcius at this time of the year is stretching the point, unless you have a massive draw of air from underbonnet instead of external to the car. In which case, fix that first, before you try anything else, otherwise you will be wasting your time - check the ducting into the air-filter box is intact and not come adrift from the box.
The MAF reading of over 1200mg/stroke is silly - it just doesn't happen. 800mg/stroke is good, 1000mg/stroke is very good......
EDIT: To confirm your MAF meter readings, see if you can take a reading off the car after a run, let it idle for more than a minute, then get a VCDS snapshot. You should be seeing somewhere around 450mg/stroke on a modern 2.0litre 4-pot, maybe 480mg/stroke if there is any residual boosting from the turbo, but much more than that would suggest a duff meter.
I was thinking the same myself tbh, i disconnected the maf and it had the glow plug light on all the time. I took the car a quick run and it dropped in power quicker. Vcds snapped the data at time of fault and showed an air intake temp of 47 degrees, so i wasnt sure if intake sensor was in maf or from another sensor? All ducting into box is clean and secure as that was one of the first things i checked. Other than one sweetie wrapper nothing was out of place |
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gregg
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Every day is a school day.
Posts: 72
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Post by gregg on Feb 20, 2019 8:25:19 GMT 1
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gregg
New Member
Every day is a school day.
Posts: 72
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Post by gregg on Feb 20, 2019 8:25:55 GMT 1
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gregg
New Member
Every day is a school day.
Posts: 72
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Post by gregg on Feb 20, 2019 8:26:29 GMT 1
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gregg
New Member
Every day is a school day.
Posts: 72
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Post by gregg on Feb 20, 2019 8:27:04 GMT 1
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Post by valhalla on Feb 20, 2019 19:39:37 GMT 1
Could do with a live-data snapshot at idle with everything connected, but EGR timed-out (give it a couple of minutes to idle) to see what the following are reading;
MAF mg/stroke Ambient pressure hPa Boost signal actual hPa Engine speed rpm
Some basics will pin this down a bit.
If the MAF meter is true, there must either be a significant leak of boost air to atmosphere, or a big bypass around the EGR circuit, as the air is being measured as rushing into the engine, but it isn't creating a boost pressure. As the MAF appears wrong at the moment, I would concentrate on that rather than the MAP sensor in the inlet manifold.
I'm surprised at the high boost target on this engine (1.6BAR gauge pressure) for the engine speed, so it's no wonder the DTC is flagging! I hope that VW have left enough "dynamic error" allowance in their diagnostic trigger-levels.....
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gregg
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Every day is a school day.
Posts: 72
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Post by gregg on Feb 20, 2019 20:01:35 GMT 1
Could do with a live-data snapshot at idle with everything connected, but EGR timed-out (give it a couple of minutes to idle) to see what the following are reading;
MAF mg/stroke Ambient pressure hPa Boost signal actual hPa Engine speed rpm
Some basics will pin this down a bit.
If the MAF meter is true, there must either be a significant leak of boost air to atmosphere, or a big bypass around the EGR circuit, as the air is being measured as rushing into the engine, but it isn't creating a boost pressure. As the MAF appears wrong at the moment, I would concentrate on that rather than the MAP sensor in the inlet manifold.
I'm surprised at the high boost target on this engine (1.6BAR gauge pressure) for the engine speed, so it's no wonder the DTC is flagging! I hope that VW have left enough "dynamic error" allowance in their diagnostic trigger-levels.....
I'll be back at it tomorrow so il get shot of it up to temperature and idling. As far as i can see and hear i have no boost leaks anywhere on engine and all pipes are tight and secure so i assume as you say the maf is showing a mass of air coming though it but boost sensor is not matching up. |
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Post by chippie on Feb 20, 2019 20:39:51 GMT 1
Do you have some way of measuring the boost pressure? That way you could rule out the pressure sensor....
Gut feeling, maf sensor is goosed...
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Deleted
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Post by Deleted on Feb 20, 2019 20:49:13 GMT 1
I don't profess to remember the specifics/details now, but one guy on the auto electrics course had an Audi 2.0 TDI with an air maf related issue and after testing at college even though no apparent fault indicated it was at fault, he went out and still bought one only to conclude later that after fitting and no effective repair to thought the PCM was then the cause!
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gregg
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Every day is a school day.
Posts: 72
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Post by gregg on Feb 20, 2019 23:34:30 GMT 1
I should have a boost gauge in garage so will try to get it rigged up. Boost sensor takes a feed of a metal pipe from inlet manifold so shouldnt be too hard to plumb it in.
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