by cacperec » Tue Sep 25, 2018 10:37 pm
of course I ment 92kpa - my mistake -sorry, got confused after using different programs.
First thing cleared after more research: diesel engine does not create vacuum like gasoline so Map sensor should show value close to barometric at idle. This creates another question: if there's no vacuum why is it lower then barometric?(100kPa in my case).
About throttle: in my case I've got 85% at idle (I assume it shows how much it's closed, not opened, right?), and 5% when driving.
My car acts weirdly most of the time and fuel consumption is too high in my opinion. Mostly it's constant no matter if driving slowly or speeding, which makes it even more odd.
What I see when it has a bad day (which is mostly) at idle and warm engine:
- MAF shows 6-8 g/s (looks too low, isn't it?)
- MAP shows 92-94 and changing between
- CEL (calculated engine load) shows 30-40% (no ac, no nothing on)
And avarage fuel consumption is 6,3 or 5,8 as I mentioned before. There were barely few times I got other values. Before 14000 km every single time it was 6.3 - no matter what. What's interesting , while driving it shows really low values like 3.8 or 4.6. I can drive like this for 40-50 km, and average consumption is not affected at all. So it looks like car "thinks" consumption is low, but it is not for real.
But from time to time car acts like it should:
- acceleration is much better
- fuel consumption lowers to 5.2 per tank even with highway speeds (120-130 km/h)
Idle values for that are:
- MAF shows 11 g/s
- MAP shows 90 kPa steady
- CEL is about 16-20% !
That makes me think the second situation is normal , and the car has some issue becouse mostly acting like in first example.
That is why I'm looking for proper values so I can compare and make dealer to fix it.
Other strange readings I have when driving:
- EGR error - many errors here, mostly below 0, reaches -50% , sometimes even -100%. From time to time gives positive value up to +50%
- I drive about 100 km per day, and every single day I can feel engine chokes (very smoothly, it accelerates and all) for a few sesonds - when it happens, instant fuel consumption shows 10l/100km and throttle is closing for this very time. It happens several times a day.
So any clue, suggestion or tip is welcome.