Engine Flat Spot between 4000RPM and 5000RPM

[SABMW]

Hi,

I have a E36 318i M43 Spec, 8 Valve. I had replaced the moto which i imported from the UK, same spec.

The car has a flat spot when driving between 4000RPM and 5000RPM loses power like no fuel or air mixture not reading, then gains power after a few seconds like after 10 to 20 seconds keeping the accelerator floored.

It idles and revs up normal, but if you tap the accelerator fast it sounds like a miss between 1RPM and 2RPM on the rev counter. Then it revs full to 7RPM cutting out.

I have checked the following,

Replaced plug leads with Bougi leads.
Replaced Fuel Filter
Replaced Air Filter
Adjusted the Airflow meter to read slightly higher then normal
Replaced plugs, Bosch Super 2
Cleaned injectors

I did notice the sensor on the exhaust has been cut wiring, think its oxygen sensor or O2 sensor. BMW Agents in Waterfront in Cape Town, said that will not make the car have a flat spot.

Not sure what to do next ?

Any ideas ?

[wille]

Hi, i have had the same problem on the same engine. I replaced the Lambda sensor and it solved all the problems. Does your MPG gauge stay still under constant throttle?