Hello Scotty and everyone else reading,

I know what is said about Renault but these cars were a pretty solid exception until it's 3rd generation and quite immortal. So, I own a 1996 MK1 1.4 (Phase 3) Renault Clio. A few months ago the engine died and won't turn on. After being seen and tested by my trusted mechanic, an ex-Renault mechanic, another retired veteran of these cars and several technicians but nobody has been able to fix it. We changed the tdp/ crank sensor, the oil temp sensor, mono-injector with another one from the scrapyard, even disabled the immobilizer on the original ECU and then tried with another (also with immobilizer disabled). Spark plugs and battery are new, so does the cables and the distributor cap and rotor. The fuel pump seems good, the wiring was tested as well as the exhaust/cat prove and MAP sensor. The car initially would idle just fine and run for an hour or so, but then shut off. At some point the total engine-on time has reduced to about 10-15mins since.

Whenever you manage to start it, it will idle a bit lean and accelerate smoothly if the gas is pressed slowly, however if you press it suddenly it will reduce rpm and try to stall like it was choking. (accelerator is using a wire, not electronic). You can even go for a rough ride of the block before it stalls to death and hardly start again after a lot of cranking or not start at all. Leaving the car to cool down with the battery disconnected makes possible to start it again with the aforementioned results.

At the moment it has the top-mounted filter removed and you can spot the whole injector contraption mounted atop the throttle body . When it stalls and dies you can hear and see it puffing some smoke/un-combusted fuel, dunno if its normal.
No vaccum leaks since the only vacuum lines it has are for leading the non-combusted fumes from the engine to a electronic valve that dumps them in a hidden active-charcoal canister - pretty fancy stuff for the time - with the sole purpose of being a complementary anti-pollution system. The engine would rev higher if one of these tubes is disconnected when idling and can I hear and feel a hissing coming from it.

Not sure what else can be but I am desperate and it would hurt my heart that such a reliable (yes, it has been for years) car ends up in the scrapyard. Can anyone help me? Any suggestion on what the problem can be?