1978bronco

ok. went thru about 50 pages of the forum and just got tired of looking.
not only that i am tired of replacing parts on the focus.
spec 2000 zx3 DOHC
the issue. when warm outside, up hill, or half tank of gas the car bucks. like it is starving for fuel. has died few times.
i initally thought it was a fuel issue. so i checked tank and it was debris free. later i changed the fuel pump. worked for a full day of driving then was actually worried i wouldn't make it home.
had my dad check the codes cause light finally came on. was running rich. so i then changed the up O2 sensor and the MAS sensor. changed a vac line off the rear side just under the throttle body cause i noticed it was collapsed. today i changed out the ignition coil. my wife informed me soon as she dropped under a half tank it started bucking again. i have no clue why this issues is continuing. act like it is running out of gas. new fuel filter. only thing i haven't changed is the fuel lines and the sending unit. i am begging for help. my dad and his employees cant figure it out. i do not trust the ford dealerships around here. should i try a new sending unit.
Michael

djzx3

Have you had the fuel injectors checked out?


And is it a manual, and how many miles?

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2000 focus wagon 2.0l DOHC Zetec
04 Subaru WRX,:)



How-to directory.

Ford focus DTC codes.

Ford= First on race day.

R.S.LOGAN

Have you checked the basics i.e plugs , wires , air filter ,timing and compresions ?

CatSkinner

What you're describing would almost sound like a leak on the sending unit, except that I don't think you'd be burning rich, unless pulling air is causing the regulator to surge. Do you have the means to check gas pressure on the fuel rail?

The only other thing I can think of that could match your issues would be a plugged cat, but that would give you issues regardless of tank level, but it would act up when the cat is warmer.

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Prius repellant, just add gas.

R.S.LOGAN

You say " it started bucking " which would indicate a misfire , possibly caused by dropping a cyl .intermittently . This would cause unburnt fuel in cyl . not firing and may be the cause of rich reading .That is why I suggested checking plugs / wires etc . Could also check fuel tank is " breathing " venting o.k .

CatSkinner

R.S. has a better explanation, check what he says first.

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Prius repellant, just add gas.