Hi there,

I´ve got a 99 fiesta MK4, 1.3 petrol which has been at the "mechanics" for TWO MONTHS, now I´ve brought it home because it´s doing my head in,and I´m determined to fix it myself . Symptoms; poor idling,rough running, burning huge amounts of petrol and stinking the place out. Done so far; new throttle sensor,new idle air valve,replaced e.c.u, and watching useless mechanics scratch their heads for two months, any ideas?

Matt

I'm presuming they checked the plugs,leads and coil pack?

yes they did, tried an alternative coil pack and leads, checked the plugs are sparking,etc.

Thanks,matt

By the way, the diagnostic computer insists the fault lies in the throttle sensor (replaced), and the engine will only start/run with the vacuum hose disconnected ( the small one behind the inlet manifold ).

Is it injection system or carbs?

Sorry, it´s fuel injection, and it´s not the injectors because they tried a replacement injection ramp,no difference.

Too much fuel may indicate the ecu sensors are faulty, have they replaced/tried the engine temp sensor/MAF/lambda sensor?

Thanks Dieselpig, to be honest I don´t know,but I´ll certainly check up on that ,after I find out where those sensors are. That would explain why the diagnostic computer is giving confusing readings (?)

Thanks Dieselpig, to be honest I don´t know,but I´ll certainly check up on that ,after I find out where those sensors are. That would explain why the diagnostic computer is giving confusing readings (?)

MAF mass air flow is located on the pipe that comes from the air box. Not sure on the other two

Lambda sensor is in the exhaust pipe near the catalytic converter, engine temp sensor will be near the thermostat in the engine block.

Thanks, I´ve found the MAP sensor and the Lambda sensor, the IAT sensor I think needs some digging around under the air filter ( it´s not anywhere on the intake tube or manifold) and the engine temp sensor will need some digging around but now I know where it is ,or should be. I´ll let you know what I find, Cheers!