[cobrabo88]

hi, i have a 03 ford focus that runs and idles fine, how ever when you hit the gas it does nothing. if you pump it long enough and if your lucky it will rev all the way to redline after pumping for a few minutes then it just stops and idles again. i've replaced the fuel filter, and the fuel regulator i think(sliver circle thing on the fuel line before the fuel rail) there is a sensor on the rail that i replaced with a used one and its still doing the same thing. i'm at a loss right now, its a 2.0 if that helps with a auto tranny. i'm positive it has to be a fuel problem cause its getting air and fire so any and all ideas would be helpful, i need my car back on the road asap!!!! also after it gets up to operating temp the oil light starts to flutter on and off and it seems to run kinda funny like it has a miss???? idk...

 

[viney266]

I know it sounds obvious, but did you put new plugs in it.

Also check the TPS...but change the plugs FIRST

 

[cobrabo88]

no i havent put in plugs and how do i check the tps? i know what it is and what it does but dont you have to have a special tool to set it?

 

[whynotthinkwhynot]

Typical tune-up time. Don't be that guy who replaces every expensive part on his EFI system only to find out he needed new plugs and wires. Just because platinum/iridium plugs are supposed to last 100k miles doesn't mean that they do, and don't loosen, or crack the insulators, plugs wires go bad no matter how much of a"high performance" product you purchase. I prefer the lifetime warranty types so it's free after the first set. It's not hard to do in these vehicles.

The flying saucer thingy is not an FPR. An FPR would have vacuum power (typically), and a fuel tank return hose. It's also nearly always on the opposite side of the fuel rail from the supply line. It's a fuel pulse damper. In these cars the fuel pressure is managed by varying the voltage to the fuel pump, so there is no return line to the tank. The other part you replaced is the fuel sensor- that's what measures pressure, temp, etc to give the PCM it's information for the fuel pump controller.

As far as TPS testing goes, I seriously don't test those. TPS problems are exactly like what you're experiencing, fairly distinct, and rarely does it fail so that a test will actually show you something. IINM, you can test for voltage reference while operating the throttle and you'll see 1-5v between 2 of the pins as you move the throttle.

You do not need a special tool, but you do need an understanding of how the TPS fits the throttle plate shaft. You'll figure that out if you pay close attention to what's going on while you remove the old TPS. You will need a torx 15 screwdriver (at least I did) then remove both the screws holding the TPS while not pulling the TPS out. Let go of the TPS, and watch it. It should tilt towards the air intake away from the engine (might go the other way, not sure since I don't have a Zetec). Anyway, you see how it tilts, that's how you put it back on. The worst mistake you can make is to force the TPS on by lining up the screw holes first- line the TPS up on the shaft, then rotate it to make the screw holes line up. If it doesn't fit flush without any force, then you're doing it wrong.

 

[COSVT03]

TPS are VERY easy to test with a DVOM or Scan tool. You just need to be patient and SLOWLY move it through its range looking for opens or skips in voltage.
And this sounds a lot like a TPS x2

 

[cobrabo88]

ok the tps has been replaced already or so i was told, i'm going to pull it back off and check it out myself and make sure its working right. if thats not it does anyone have any other ideas of what could be doing this. so far its been fuel filter, tps, fuel damper, and the sensor on the fuel rail and still wont rev...

 

[84572]

Can he test the TPS like you can on my Mustang by inserting needles in the correct wires and using a voltmeter set at dcv? That's the way I do it. If so it's a snap. Also how many miles on your car? Could be timing belt slipped.