Experimental results on the influence of angle and cell geometry on pulse height measurements in a multiwire proportional chamber (MWPC) are presented. Two track orientations are mainly considered: (a) tracks parallel to the wire plane and (b) tracks traversing the gap with one wire touched. In case (a), the positive induced pulse effect is analyzed: pulse heights have to be corrected by factors of 1.3–1.7 and wire inefficiency can be found up to 20%, depending on the cell geometry. The saturation effect starts earlier in case (a), but the influence of the angle between track and wire when approaching 90° is moderate. On the contrary, this influence is very effective in case (b). A detailed study of this phenomenon is then presented with a description of possible mechanisms involved.