1998 ford taurus stumbling and stalling problems?
I have a 1998 taurus with the 24 valve DOHC. It stumbles only when up to temp. I have replaced fuel pump, regulator,filter and relay, and pcv valve in the fuel delivery system, I have replaced the air charge sensor, mass air flow, tps and Idle air control valve. Had this thing checked for vacuum leaks and there are none. The only thing i haven't changed is the O2 sensors which have 140,000mi on them. I am suspecting i have one that is going bad. The car only stumbles for a second when you crack the throttle, but then takes off like a shot.Like i said this only happens when its up to temp, first thing in the morning it runs without a problem. No other problems with the car at all. Any ideas as to what might be the problem? Am i on the right track?
I forgot to add that the check engine has not come on at all during this problem.
the throttle body is cleaned each oil change, the plugs and wires were changed at 100,000 like recomended, unsure about the temp sensor since the engine stays pretty cool according to the gauge, and as far as fuel, even though this car is NOT E85 compliant, If i run E85 the problem goes away. So i know its not the timing chain. When i do run E85 however the obdII light does come on and gives me a lean burn, and a slow response in bank 2 sensor 1, that is the only code that has ever come up. hope the additional info helps
I also want to add that the plugs and wires were replaced with ford parts(motorcraft double platinum plugs and wires) and the fuel I only buy Shell 93 from one station unless i get E85, and for those who dont know what that is is 85% ethanol and 15% gas.
I have a 1998 taurus with the 24 valve DOHC. It stumbles only when up to temp. I have replaced fuel pump, regulator,filter and relay, and pcv valve in the fuel delivery system, I have replaced the air charge sensor, mass air flow, tps and Idle air control valve. Had this thing checked for vacuum leaks and there are none. The only thing i haven't changed is the O2 sensors which have 140,000mi on them. I am suspecting i have one that is going bad. The car only stumbles for a second when you crack the throttle, but then takes off like a shot.Like i said this only happens when its up to temp, first thing in the morning it runs without a problem. No other problems with the car at all. Any ideas as to what might be the problem? Am i on the right track?
I forgot to add that the check engine has not come on at all during this problem.
the throttle body is cleaned each oil change, the plugs and wires were changed at 100,000 like recomended, unsure about the temp sensor since the engine stays pretty cool according to the gauge, and as far as fuel, even though this car is NOT E85 compliant, If i run E85 the problem goes away. So i know its not the timing chain. When i do run E85 however the obdII light does come on and gives me a lean burn, and a slow response in bank 2 sensor 1, that is the only code that has ever come up. hope the additional info helps
I also want to add that the plugs and wires were replaced with ford parts(motorcraft double platinum plugs and wires) and the fuel I only buy Shell 93 from one station unless i get E85, and for those who dont know what that is is 85% ethanol and 15% gas.