I have a 2001 screw 4.6L that during a drive home yesterday all of a sudden had the flashing od light syndrome and no shift out of 2nd and the engine running like it was on 4 cylinders when applying any power. After some research here I have found that f23 under the hood is blowing. I replaced it and within 5 minutes it blew again (while driving).

What are some reasons this fuse would keep blowing?

The manual states that this fuse is the HEGO sensor and auto transmission. What is the HEGO sensor Are these the exhaust sensors in pipes? (2 on each side)

Thanks for any help
Pax

 

The sensors themselves create voltage in order to determine the oxygen in your exhaust. But that itself isint enough to blow the fuse. They dont produce all that much. But yes in all basics your 02 sensor. You might have a shaved wire somewhere causing this to happen. Driving points towards the motion of wires rubbing on metallic pieces.

 

Search keyword "F23" for previous discussions.

 

Thanks for the info. It confirms what I suspected and could gather from my research. I will check into my sensors.

thanks
Pax

 

Thanks for the suggestion.

I had already searched that exact phrase and read tons of articles and yet some things remained unclear.

I now understand, from further study here, and on other forums, that HEGO's are O2 sensors and so, F23 powers the O2 sensors as well as my tranny. That explains why when it blows, that the tranny goes into limp home mode and will only drive in 2nd and why the engine runs like crap above anything other than an idle. I just needed to know where to look for possible shorts in the circuit that continues to blow each and every new fuse put into f23. Will check out my sensors tomorrow and see what's up.

Pax

 

Well thought

 

Pax,

Check the O2 sensor harnesses first - exhaust manifolds and front driveshafts are usually involved.

Other than that, you'll have to check harness routing, especially near the firewall. Insulation rub-throughs are tough to find except by visual inspection unless you have a short-circuit detector.