What fuel is recommended for Mercedes A160 1999 model? Unleaded 91, 95 or 98?

leave the fuel line of the prefilter and turn on the ignition
the pump should work and pump the tank to near empty
use care as the fuel is very volatile and collect it in a bucket or other dish or fuel container

Weak mixture is main cause ,but what is the psec on this engine as modern fuel is unleaded and if this is a 1990 then it could have been made to only run on leaded petrol ,unleaded engines have a stelite coating on the valve and the seat in the head to run on unleaded fuel ,or the valves have been ground in more than once and the coating has been worn away .Check with the dealer if this model is designed for unleaded fuel ,if it has a cat on it then its designed for unleded fuel

According to page 10-3 of the 2001 Nissan Maxima Owner's Manual:

FUEL RECOMMENDATION
Unleaded premium gasoline with an octane
rating of at least 91 AKI (Anti-Knock Index)
number (Research octane number 96)
If unleaded premium gasoline is not available,
unleaded regular gasoline with an
octane rating of at least 87 AKI (Research
octane number 91) can be used.
However, for maximum vehicle performance,
the use of unleaded premium gasoline
is recommended.

Engine "knock" is not just an unusual sound - but over time can cause real damage to the engine. You *should* use fuels with the recommended octane levels, but if you choose to use fuel with a lower octane level due to reduce fuel costs - do not repeatedly use fuel that causes engine knock. Find the "sweet spot" between the cost of lower octane fuel and an octane level that does not cause knocking. Expect fuel economy and performance to drop with lower octane fuels, too.

Good luck!

That is not a problem it is actually recommended that you use premium 93-94 Octane fuel, if you put turbo blue (115) in it that would be a problem but 93-94 octane is the VW recommended fuel type.

Gasoline for this 2.3L 4C

Unleaded is recommended for this car but it is compatible with LRP since it has no catalytic converter.
I am asuming you are in South Africa? Have a look at the NAAMSA fuel compatibility database.

89 octane/ron upwards....unleaded.

Your jeep has two engine options, one was a standard 4.7 V8 and the High Output V8. Below is the recommended octane fuel rating.
Unleaded regular, 87 octane (R + M)/2 - Standard;
Unleaded premium, 93 octane (R+M)/2 recommended - High Output
Thank you for using fixya and be safe.

dear friend-you must use unleaded as that is what you vehicle is desight for

The best oil for any car is 5W-30 synthetic, I personally recommend Mobile 1. 5W-30 Synthetic flows more rapidly to engine parts thereby reducing "dry start" wear. In addition, full (not part) synthetics contain fewer additives (they don't need them) than conventional oils. Conventional oil additives "burn off" rapidly (500-1000 miles) after an oil change and sludge accumulates over time as a result.

Synthetic oils use much less of these additives (5% vs 20-30%) than conventional (Dinosaur oil) so there's much less sludge to build up. Synthetic oil also has a more uniform molecule size, this extends oil longevity and reduces running temperature.

I've personally used Mobile 1 for many yeas in my cars and would recommend it although I'm quite sure that other FULL synthetics would offer similar benefits.