Is it normal to get shitty gas mileage right after an oil change?

No your engine's fucked m8.

>>15580355
dubs of truth
Ye OP, your engine's fucked, is a check engine light on?

>>15580326
How shitty? It could just be you being paranoid and not realizing that half the mileage comes from driving habit.

>>15580326
>Is it normal to get shitty gas mileage right after an oil change?

Check your dipstick to verify you have enough oil and that the oil "looks new" since you did get an oil change.

Psychology of expectations also affects people in how they perceive something should be better after an oil change using the same type of oil. Ideally, nothing changes after the oil change. If your mileage did improve (with all other factors equal), then the previous oil was worn out and that is a bad sign you went to long. If your mileage didn't change, then that is good. You changed within the limit. If worse, maybe you put in the wrong oil (something thicker).

>>15580326
You may have over filled it.
Causes the crank to dip through the oil and can make your mileage drop

>>15582368
Not OP, but I put 3.8 liters instead of 3.1, how bad is it?

>>15582493
post dip stick

>>15582501
Something like 0.5 cm above the maximum

>>15582508
This information is irrelevant without knowing how long the marked area is.

>>15582508
ahh, not great OP.
Get a big syringe and stiff some nylon tube so you can draw the excess oil out through the dipstick hole.

>>15580480
Like 10-20% more consumption.