02 sensor information needed

[JayTye4k]

My car stalled out on me yesterday when I cranked it and the rpms have been lower than usual at idle. I've already replaced the IAC, cleaned the MAF, new plugs, wires, fuel filter, and seafoam. A friend told me that he had the same problem and replaced the o2 sensor, which fixed it. Could a failing o2 sensor cause your car to stall out like that and bog down at idle?

Also, how many o2 sensors do I have, which ones should I replace, and is it an easy job to do myself?

Thanks!

Jay

 

[newbi]

Check out the EGR system first. Look for vacumn leaks at the EGR control solinoid , cracked lines going from exhaust manifold to DPS switch and operation of EGR valve. Any of these will cause poor idling and knocking once the engine heats up.

 

[V8BoatBuilder]

Is your check engine light on? You have a 95, which means your truck has OBD-I diagnostics. You can retreive codes from a reader ($30 at autozone) or using a paperclip to short out a connector to make the light flash the code.

A stalling can come from lots of different things, but since you have replaced plugs, wires, fuel filter, it does seem to point to another part. A failing O2 can cause your truck to run too rich or too lean, which could theoretically cause stalling out.

 

[JayTye4k]

no check engine lights and it runs fine after it warms up..after about 10-20 miles of driving.

 

[V8BoatBuilder]

no check engine lights and it runs fine after it warms up..after about 10-20 miles of driving.

The O2 sensor doesn't kick in untill it is warmed up, and the engine is in closed loop mode.

Try doing diagnostics on your ECT (engine coolant) sensor.

 

[JayTye4k]

I replaced that too.. and cleaned the MAF. Could this be a sign that my fuel pump or fuel injectors are bad? Thanks alot for your insight V8Boatbuilder!

 

[V8BoatBuilder]

Go to autozone and buy a fuel pressure gauge for $40, that will clear up many questions.

You should be seeing a reading of 35-40psi with the ignition on and the truck off, and the fuel pump should hold this reading for a few minutes. With the engine on, and idling the fuel pressure should be 35psi.