Metering pump

A metering pump, especially for feeding fuel to a vehicle heater, comprising a delivery plunger, which can be moved to and fro for delivering liquid medium, a guide sleeve, which partially accommodates the delivery plunger and guides same for the reciprocating movement, wherein the guide sleeve with an inner surface thereof defines a pump ejection chamber and it defines with an outer surface thereof a channel arrangement leading to the pump ejection chamber, wherein the guide sleeve is carried in a carrier element and is in contact with the carrier element by its outer surface essentially over the entire circumference in a first length area and is located with its outer surface at a spaced location from the carrier element in a second length area, wherein the channel arrangement is provided between the carrier element and the guide sleeve in its second length area, is characterized in that in its second length area, the guide sleeve has at least one support area, with which it is supported in relation to the carrier element.