The Clio largely replaced the Renault 5. The engine range available at launch included 1.2 L and 1.4 L E-type "Energy" petrol I4 engines and 1.7 L and a 1.9 L diesel engines. The petrol engines all received an electronic fuel injection system in place of carburettors in 1992, in order to conform to new pollutant emission regulations.
In March 1994, the Phase 2 model was launched, with small updates to the exterior and interior of the Clio. Most noticeable was the change in the front grille from two metal ribs to a single colour-coded slat grille. The bump strips were made slightly larger and rounder, and the car's trim level badge was incorporated into the bump strips. The badges on the tailgate strip were moved up onto the tailgate itself and the tailgate strip was given a carbon fibre look. The rear light clusters were given a slightly more rounded bubble shape to them, giving the Clio a more modern look.
In 1996, with the arrival of the Phase 3 facelifted Clio, the 1.2 L Energy engine was replaced by the 1149 cc D7F MPi (Multi Point Injection) DiET engine, first used in the Renault Twingo; for some time also, versions were available with the older 1239 cc "Cléon" unit from the original Twingo. The cylinder head design on the 1.4 L E-Type was also slightly altered for the Phase 3 models in a bid for better fuel economy. This resulted in the engines producing slightly less power than their earlier versions. The Phase 3 Clios had a slightly more noticeable update than the Phase 2's. The Phase 3 has different, more rounded headlights, incorporating the turn signal in the unit with the headlight. The bonnet curved more around the edges of the lights. The tailgate incorporated a third brake light and a new script "Clio" name badge, following the same typeface as contemporary Renaults. Some mechanical improvements were also made.
During 1991, a 1.8 L 16-valve engine producing 137 PS (101 kW) (also first seen in the R19) capable of propelling the car to 208 km/h (129 mph) was introduced to the Clio engine range, known simply as the Clio 16S in France (S for "soupappe", the French word for valve), and Clio 16V in export markets. As well as having higher top speed than a regular Clio, the 16S sported wider plastic front bumpers, an offset bonnet vent, wider rear bumpers and uprated suspension and brakes, and colour-coded front mirrors and bumpers.
Renault also released a warm hatch version of the Clio. It was aesthetically very similar to the Clio RT & 16S, but with the addition of a 110 PS (81 kW) 1.8 L 8-valve engine, side skirts and disc brakes on all wheels. This was badged as the RSi. As with the Volkswagen Golf MK2's 8- and 16-valve GTI variants, the 8-valve model had more torque at lower engine revs and was more of a "drivers car" on winding roads.
The Clio was voted European Car of the Year for 1991, and soon became one of Europe's best-selling cars, as well as the first Renault to be consistently among the top-10 best sellers in the United Kingdom. UK sales were helped by a famous television advertising campaign by Publicis shot in France, featuring the two main characters of Nicole (played by Estelle Skornik, who was not French nor did she have a driving licence at the time) and Papa. From 1991 to 1994, trim levels were identical in every European country.Source: Wikipedia Renault Clio Article.