Stratus problem

Good day to all, my problem is with a Stratus 2002 Motor 2.4 What happens is that the engine in low is unstable and sometimes turns off, already check the IAC and the TPS and they are fine but the MAP data does not have them, off with open switch gives me 3.7v and igniting me 3.4v and lowers but it varies a lot if someone can help me I would appreciate it very much the car in low

Check the fuel pressure, there may be the problem as a multipunto, the pressure can come down but the MAP can only see it with a oscilloscope and the waveform must vary slightly and without sudden cuts (both on low and high but with load, with a moving car, not stopped) if it has sudden cuts boog Fuel (it is close to the injectors rail) or the fuel regulatory valve, to the filter could be covered OK. Not everything is to measure with a tester but you must also use oscilloscope, vacuometro, manometro, compressro among others.

Hello once I had a problem with a Cirrus 2.5 and the problem was what I imagine turned out to be that this car was removed from catalysts and all the carbon dioxide like Tizne arrived the oxygen sensors what Ise was removed clean them well washing them with carbuclean and re -install if it improves but does not fix the problem you have to change the oxygen checlo 2.4 The catalyst was taken away from the oxygen sensor ... !!!

If the failure is by rpm oscillation, you have a lot to check the temperature sensor is also very tested at this point and also as a empty or false air input can also affect you even a poorly purged evil of the freighting system.