2000 4.0, AW4, 85k miles
Cone filter, 2.5 inch exhaust
Short in O2 sensor circuit, I would assume it runs in open loop mode
The issue is that when starting, the engine will crank over many times than usual, maybe for 10 seconds on some occasions before actually starting. But after it starts, it will run just fine. It doesnt hesitate or feel like it is lacking in power. It only has a problem with starting. On top of that it only happens about 60% of the time, independent of how long it has been off.
Don't really know where to begin diagnosing this problem. Obviously you need a few things to start an engine:
It cranks over, starter seems to be working fine.
I haven't checked plugs yet, but considering the engine works just fine after it has turned on, that seems to be an unlikely culprit.
That leaves the fuel system. I don't smell leaking gasoline, so hopefully all of my fuel lines are with out leaks. Nor does it misfire after startup, so I would hesitantly rule out injectors. Then the last part being the fuel pump, I am not exactly sure how to test that for proper functionality, but once again, it works fine AFTER startup.
I don't really know where to look next.
Also, heat soak ran through my mind. I have had that particular problem before and solved it for the most part by wrapping the fuel rail and a good portion of the injectors in insulating foil.
Suggestions?
Cone filter, 2.5 inch exhaust
Short in O2 sensor circuit, I would assume it runs in open loop mode
The issue is that when starting, the engine will crank over many times than usual, maybe for 10 seconds on some occasions before actually starting. But after it starts, it will run just fine. It doesnt hesitate or feel like it is lacking in power. It only has a problem with starting. On top of that it only happens about 60% of the time, independent of how long it has been off.
Don't really know where to begin diagnosing this problem. Obviously you need a few things to start an engine:
It cranks over, starter seems to be working fine.
I haven't checked plugs yet, but considering the engine works just fine after it has turned on, that seems to be an unlikely culprit.
That leaves the fuel system. I don't smell leaking gasoline, so hopefully all of my fuel lines are with out leaks. Nor does it misfire after startup, so I would hesitantly rule out injectors. Then the last part being the fuel pump, I am not exactly sure how to test that for proper functionality, but once again, it works fine AFTER startup.
I don't really know where to look next.
Also, heat soak ran through my mind. I have had that particular problem before and solved it for the most part by wrapping the fuel rail and a good portion of the injectors in insulating foil.
Suggestions?