Depending on the spark plug manufacturer, the plugs for a 1988 Mercedes 190E 2.3 should be gapped between .030" to .032". Bosch and Denso recommend .032", while NGK recommends .030".
It has no differential plug.
Gaps are from .028" thou to 0.035" thou. Preference is for 0.028" thou.
To remove the spark plug wire in 190e one needs a long nosed plier. Next go for the metal part just above the plugs and grip them tightly and pull up. To fix it all you need to do is to push it with your fingers. Done
Yes, you can find one the side of the differential facing the trunk.
As per page 95 of the owners manual The electrode gap is 0.8 mm (0.032 in)
To change differential fluid on a 1997 CR-V the vehicle needs to be lifted up to reach the rear differential. Find the drain plug located on the underside of the unit. Pull the plug and drain the fluid, when done place the plug back add fluid into the fill hole which is located topside of the differential.
.045
Mercedes 2.6 (m103) oil pressure reliefThe oil pressure relief valve on a Mercedes 190e 2.6 (103) is mounted in the oil pump housing. Access is by removing the sump where the oil pump housing is located at the front of the engine. The relief valve consists of four components, a screw plug, a compression spring, a guide pin, and a piston. Remove the screw plug and withdraw the spring the pin and the piston. Refit in the reverse order to removal and torque the screw plug to 50Nm.
The rear differential plug is located on the inside top part of the differential. Where the drive shaft connects.
unplug the connector, remove the oxygen sensor, it is located under the vehicle at the catalytic converter. install new oxygen sensor, plug in connector. done.
The fill plug is on the end of the differential. To access this, you will need to crawl underneath your car, and lok at the middle of the axle. There are two plugs on the differential; a drain and a fill plug. The Fill plug is obviously the plug closer to the roof of the car.