Service light came on code reading P1115 change catalytic and both 02 sensor

1996 900 s

1996 900 s there was a p0443 and a p0449 also which came up to oxygen sensors change both both read a low resistant

I have checked this out to find that ECM would be bad. Being If I going this route may I ask one question? Could it be possible that the mass air flow or idle control valve have malifuntion to the fuel be a cause. I have a borrow code reader it read that manufacture fuel air control malifuntion. Leaving me to think of mass air flow or idle control valve malifuntion. Is this possible or not. Everything pass but the cat and oxygen sensor. When I have remove the pre oxygen sensor it was carbon build up. In week time.

I HAVE CHANGED THE ECU AND STILL HAVE THE CODE P1115 so that was not the answer. It still reading fuel and mixture error calatytic heated. So where do we go from

I have purchase a oxygen sensor for front of the catalytic it was a replacement connection could that give a fault Reading it tape up and cover well. They said the oxygen reading come along the line.

The o2 sensor is located below the exhaust manifold before the cat. Yes the light came on

4 cylinder. 2.3
carburetor

This Saab. Vehicule is running great. I have make it a very comfort ride. Engine run like top. But this engine light I can't t remove. I have until the 11 of November to remove the light or take it off the road.

Am So can this be fix or should I move on to another mechanic. So far I having gotting any answer that would make any sense of this. ÀNy thing to run with a short where or malfunction where. I have worked on vehicule all my life this one got me held up. You said the only thing you see that the would come is o2 sensors catalytic conventor but that can't be true. The ECU control the operation of flow to the fuel and air to meter them. Would that be a true statement. If so what else would control the service light. MAF. IDLE CONTROL VALVE. EMISSION CONTRL VENTS OR PURGE. VALVE. If these are not a controllable to ECM to operate the service light than where are we.

Sir I went and changed the wirer connect between the oxygen sensor Before the catalyst this connect was a universal kit. Thinking that where the poor connect is. Also change the engine heat sensor to the ECU. I have to take it for a ride to see if the cycle will clear the code.

Well after taking the vehicle for it cycle to turn off service light another trouble code arose p0411 second air flow injector flowing incorrect.

Well no the p1115 is still on. The is reading secondary air flow injector flowing incorrect. I have check the system to find air flow is flowing strong. I have waited and cycle the temperature five times to the engine. Hot to cold to see how the secondary air injector was flowing and how much. I found no change there a check valve that on the injector rail to the exhaust manifold I had replace that earlier this year I found no moisture or carbon resin in it.