Citroen ZX 1.4i Running Problem

[juno106]

U have a 1997 Citroen ZX 1.4i. With multipoint Magneti Marrelli 1AP injection.

It is suffering from a number of problems which I assume are related. When stationary the revs are irratic and sometime stick at 2000 rpm. When moving along at slow speeds in 1st or 2nd gear between 1 and 2000 rpm the car hunts along. When you lift off the accelerator when crusing the car also hunts. Recently it appears to flood and stall a few seconds after starting from hot or cold, then clears itself.

I have replace the following components.

Fuel Pressure Regulator
MAP Sensor
Crank Angle Sensor
Throttle Potentiometer
Idle control Valve
Coolant temperature sensor.

I have not replace the coil, air temperature sensor,or o2 sensor, as the problem is there when cold i.e. when the o2 sensor is not active, nor have I tried a different ECU.

I do not want to spend any more time and money and cannot afford to leave the car with a specialist.

Apart from fitting a carb and distributor from an older engine I am at my the end of my tether.

Would be very grateful if anyone knew what else could be causing this problem.

 

[Mursal]

As you have quite a bit changed, it sounds as though the engine is taking in air into the inlet manifold from an uncontrolled source.

You may have a vacuum pipe cracked? Do a visual check for cracks or loose pipes on the manifold. They can be hard to find.

Did you notice any dirt around the old Air control Valve when changing it? Would the inside if the manifold still be dirty? Carb cleaner if you think it is.

It can be very difficult just to pin point the cause of a fault like this.

 

[Burnerman]

Sincerely I hope the fault is in what Mursal has detailed above - if it isn't I reckon a new throttle body could be needed. Unfortunately, these things from a breakers yard don't tend to be much use.
John

 

[advancemaintenance1]

i had a very similiar problem with an e36 bmw.
after paying some so called autoelectrician to diagnose and replacing all the parts he showed me on the printoff and also changing rear silencer all to no avail it turned out it was a few little air leaks on some hoses, tightened all the jubilees and changed 1 pipe £3.50 ish if i remember right and abracadabra no more hunting
so after spending in excess off £250 for absolutely no reason whatsoever the car worked perfectly for less than the cost of a pint