Missfire makes a wide band read rich or lean??
- Thread starter Black02GT
- Start date
My bet: lean. Because it'll see excess O2. It can't "see" fuel at all. Only O2. Now if your vehicle has a crankshaft position sensor, as most do, the PCM will read the extra O2 from the sensor and the crankshaft arriving later than expected, and make the call on it being due to a misfire. Or at least, it could do it that way. That's my guess.
I agree. 99% sure it reads O2 (hence oxygen sensor) not fuel sensor. Well hopefully that's good and my issue is a poorly wired J&S. Brought my car to a shop since I don't have time and they are straight trash.
Guess back to finding time to do it myself (correctly)
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Lean. Not a guess here either.
Thank you sir, all makes sense. Just wanted to have confirmation before I got mad.
Asked them to solder in the connection for the J&S like I would by the ECU instead tapped in with T-taps right after the coil covers. heat, oil, vibration, etc with t-taps just ripped apart the insulation on all the coil wires. ****ing Mickey Mouse shit, plus electrical tape in an engine bay is the stupidest shit... Wondering what was burning the other day found a cordless Matco shop light melted to my headers...
If they just tapped into the wire but didn't cut it if your handy with a small pick set you can push the terminal out and put a piece of heat shrink on it and put it back in, doesn't look to bad but looks a LOT better than tape.
That's a good idea. Just have to unhook a but of stuff to get some slack to work with. Thanks.
Upstream will always read lean. Downstream will normally read rich since the cat uses up the O2 to catalyze the unburned HC (if you have cats....otherwise, they will read lean without cats as well).
It will confuse the hell out of you if you don't keep in mind that the sensors always read O2 only, not air to fuel ratio.....
It will confuse the hell out of you if you don't keep in mind that the sensors always read O2 only, not air to fuel ratio.....
wait, the PO used the Ttaps for the J&S at the motor? good lord. The instructions say to do that in the cab where it's not in the elements or get an MSD 2 step harness
No, shop I brought the car to did... Well known Mustang shop for decades but have some younger guys there I'm starting to question. Attached the J&S box to the kick panel then ran the wires into the engine bay instead of just using the ECU wiring literally in the kick panel it's on. Had I done it definitely would have put the box in the glove box and tapped by the ECU. Car was already there though so asked them to do it.
So going to have to pull the coil harness out and get as much room to work, de-pin and heat shrink. Little ****ers aren't easy to get off in tight places either.
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