[rfourt]

We just bought a 2002 Focus SE Wagon with the Zetec engine. Things have gone really south with the car since buying it.

Replaced the alternator due to bad voltage regulator. Of course we all know how much fun replacing the alternator is!

Now the car has started misfiring and it threw P0460 and P0193 codes. I replaced the fuel pressure sensor and it cleared the P0193 code. The fuel level code (P0460) still shows and the car runs like crap. If you give it just a little gas, it will be smooth, but if you accelerate at all, it starts humping. It almost sounds like it's getting too much gas.

The line from the Evap Purge Cannister to the fuel pressure sensor has been partially replaced with a standard EFI hose and clamps. Don''t know if that would affect it.

Also, a weird side note, the temperature and fuel gauges don't respond right away. About 10 seconds after starting the car, the gauges will come on.

I'm new to the forum, so be gentle....

 

[BC_ZX3]

Obvious question: Time of last fuel filter replacement? Should be done every 25K miles. "Humping" when applying gas is usually fuel starvation. There was a problem with fuel pumps in the early model years. Your situation doesn't quite fit those symptoms however (engine cutting out/stumbling on high speed angled corners such as freeway off ramps.)

Evap Purge Canister to fuel pressure sensor line...? The two components are unrelated.

btw, welcome to FF.

 

[rfourt]

Thanks for the reply. We just bought the car, so I don't know even IF the fuel filter has EVER been changed. I'll check fuel pressure at the rail and see what I'm getting.

My bad on the Evap to FPS. It is the supply line to the FPS at the rail.

The reason I thought it might be flooding is that at no load, in neutral, the car will rev past the sputtering and hit high rpm's no problem. It's just the initial acceleration from idle that causes it to sputter. In DRIVE it's another story.

 

[BC_ZX3]

If the fuel filter has never been changed, then I'd change it as a matter of routine maintenance. If it's badly clogged then that may be your problem and it's a $10/20 minute fix.

You may have a problem measuring fuel pressure at the rail since a stock car has no fitting.

If flooding is causing a misfire, you may get a CEL (Check Engine Light) indicating a misfire is occuring and which cylinder. If the misfire is severe enough to affect the catalytic converter (emissions), the CEL light will flash as the misfire occurs.

Sorry, but I think your two codes when taken together may be pointing to fuel pump problems. The Focus fuel system is somewhat unique in that it is "returnless"; there is no return fuel line back to the tank as in other "looped" systems. Instead the ECU modulates the voltage to the pump to provide the correct fuel pressure for a given engine load. The ECU calculates/monitors the pressure with the pressure sensor.

Anyway, fuel filter first then go from there.


DTC code specifics for reference:

P0193 - Fuel Rail Pressure Sensor Circuit High Input (FRP)
The comprehensive component monitor (CCM) monitors the FRP sensor circuit to the PCM for high voltage. If voltage were to fall below a calibrated limit and a calibrated amount of time during testing, the test will fail.
FRP signal shorted to VREF or VPWR.
FRP signal open (gasoline only)
Damaged FRP sensor.
Damaged PCM.
High fuel pressure (caused by damaged fuel pressure regulator) NG.
A FRP PID value during KOER or KOEO less than 0.3 volts for gasoline or 0.5 volts for natural gas vehicles (NG) would indicate a hard fault.

P0460 - Fuel Level Sensor Circuit Malfunction
The PCM monitors the fuel level input (FLI) circuit for electrical failure. The test fails when the signal moves outside the minimum or maximum allowable calibrated parameters for a specified fuel fill percentage in the fuel tank.
Empty fuel tank
Fuel pump (FP) module stuck open
Incorrectly installed fuel gauge
Damaged instrument cluster
CASE GND circuit open
FLI shorted to VPWR
Damaged PCM
Overfilled fuel tank
Fuel pump (FP) module stuck closed
Damaged fuel gauge
FLI circuit open
FLI circuit shorted to CASE GND or PWR GND
CSE GND shorted to VPWR
Monitor FLI PID and FLI V PID in key ON engine RUNNING. FLI PID at 25% fill (with non matching fuel gauge) and FLI V PID less than 0.90 volts [for FLI PID at 75% fill (with non matching fuel gauge) and FLI V PID greater than 2.45 volts] indicates a hard fault.

 

[rfourt]

What a terrific response! Thanks for all the info. I think I've come to the right place for answers. It never occurred to me that the system was returnless.

Anyway, thanks for your time and patience!

 

[rfourt]

Thanks again for all your help.

PS, since the voltage reg had been bad, I decided to replace plugs, wires, coil pack along with the fuel filter.

The damn spark plugs were original (123K miles). Anyway, she runs great now and I really appreciate your help.

 

[BC_ZX3]

Glad to hear it was an easy fix.

Might want to do all the fluids while your at it. The Zetec motor seems to perform well for many miles when properly maintained.

btw, cam belt replacement is technically due at 120K miles. []

 

[xecutionr]

I just had this same problem happen to me... it was as if my power cut off at high rpm... one of my coils on the coil pack had carbon or some kind of build up on it... do you guys think that could be my problem? the coil pack?

 

[rfourt]

Since I did the stupid thing and replaced several components at once, I can't say for sure which fix fixed the problem. The fuel filter is a no brainer since it's so cheap and relatively easy to install. The coil pack too is easy but costs more. Plugs and wires, IMO, should generally be replaced together.

That being said, I know on my 2002 the plugs, wires and coil pack were all original and 123K miles old. My code scanner showed adequate fuel pressure but I replaced the filter anyway. If your car has a lot of miles and has not had these components replaced, $125.00 should cover all the parts and a couple of hours of your time would be a good investment.

 

[duellinski]

Thought that I'd tack on this thread as my situation is similar but different.....

Hoping that someone can point me in the right direction. I have a 2001 Ford Focus 2.0 Ztec DOHC. I bought the car with 182K miles on it. Ran really well for a few weeks and then all of a sudden as I was pulling into a parking spot it died on me. I was pretty low on gas and was just going to put gas in it but went in to do my grocery shopping real quick. Came back out and no start. It kinda changed sounds too as I was trying to start it. Almost like there was no resistance. So I asked a friend to watch as I cranked and the serpentine belt was turning so I knew the start was engaging. ALmost sounded like it wasn't. So then I thought, timing belt. Sure enough, loosened the cover and had someone watch as I cranked, not turning. So I put a new belt on. Yay. Worked for a few days and then not so good.

I had noticed that ever since I bought it that it would stumble for a second at different speeds and RPMs. I didn't think much of it and thought I would fix it in the spring as it's Michigan and cold now. Well one day I was almost to work and it started running really rough. Almost like I had dropped a cylinder. So I got it home and took it to my cousin's to hook up his scanner that links to his tablet. It was throwing a few codes.

P0455 Evap Leak (Large Leak)
P0457 Evap Leak (fuel cap loose/off)
P1237 Manuf Defined
P0125 Insufficient Coolant Temp for closed loop
P0302 Cyl 2 misfire

Reset the codes and see what was what and still had

P1237 Manuf Defined
P0125 Insufficient Coolant Temp for closed loop
P0302 Cyl 2 misfire

The other thing that we noticed was the fuel pressure was high. It was pegged at 81.8PSI even though I read that it should be at about 30-70 depending on RPMs. So I went to the stealership and looked at the pricing and availability of the Fuel Rail Pressure sensor (they were calling it a Fuel Injector Sensor) and they said it was $160 but on backorder with no promise date And the Fuel Pressure Regulator ( hose with the metal diaphragm inline) was $130. Yikes! So I went to the junkyard in hopes of getting a good one or at least one that should maybe change the symptoms. I found both parts for $16 and off a car that had the fuel system still intact thankfully so hopefully not exposed to the elements. I put that on and I am still seeing the high pressure but at least now it is registering a code for it. These are the codes I am getting now.

P1237 Manuf Defined
P0125 Insufficient Coolant Temp for closed loop
P0193 Fuel Rail Pressure Sensor circuit high
P0302 Cyl 2 misfire

Sorry had all this typed up before and lost it. I forgot this part I replaced the thermostat for the P0125 code as I could only get decent engine temp when sitting. As soon as I started driving it went away....yup, thermostat. (BTW, anyone have a tip on replacing those stupid torx screws that hold the thermostat housing together??? What a stupid design IMHO) So that code should no longer be an issue.

I tried clearing the codes a couple times after replacing the sensor and dampener and it was the same thing both times.

So my question is two fold. How come now that it is actually seeing that the pressure is too high is the pressure not being regulated down? Could a bad fuel filter cause that? It's restricted so the pump is pumping harder to push through? But why would it push so hard and not at least fluctuate some? I did notice with the newer/old FRPS (I can't remember now the exact situation) where the pressure went up to 82.something momentarily but it pretty much stays pegged at 81.8. No matter what the RPMs are. I notice that the TPS sensor is fluctuating so it's sensing the change in throttle position. Is there something wrong with the pump and it's not able to vary the voltage to regulate the pressure? Is there something wrong with the ECM and it's not able to regulate the voltage to the pump to vary the pressure? How would I check that? Is there some test points I can take some voltage readings to figure that out? I read some of the other posts that talked about the vacuum hose from the sensor having fuel in it. Neither the old one that was on there or the new/old one from the junkyard had any fuel in this line so I don't think that was an issue. I also thought I read something about the formed elbow that connects to the intake sometimes collapses? (That may have been on the PCV valve, I don't recall) I don't believe this is happening on this one though. Is there a replacement hose for this or do most people just replace it with some hard elbow inline connectors?

Second question, is the misfire related to the high fuel pressure? I ohm'ed out the wires and I think it was 6K, 5K, 6K, 3K for wires 1-4 respectively. But nothing with a really high resitstance, especially not cylinder 2. I even was twisting them around a bit when doing the readings. Could I have a bad coil module? I'd rather not have to replace it if I don't have to. It's only like $70 but that's $70 I gotta earn. Is there something else I should be checking?

Thanks for any help you guys and gals can give.

 

[BC_ZX3]

I can only offer the info below which would point to a fuel pump or FPDM fault. A faulty fuel pump or improper fuel system pressure could possibly cause misfires so I would attend to the potential fuel delivery problem first. Easiest thing to do first would to be make sure wiring to FPDM is sound. The FPDM is under the passemger side rear seat cushion.

P1237 - Fuel Pump Secondary Circuit Malfunction
Indicates that the FPDM has detected a fuel pump secondary circuit fault. The FPDM will send a message to the PCM through the FPM circuit, indicating that this failure has been detected. The PCM will set the DTC when the message is received.
Possible causes:
Open or shorted FP PWR circuit
Open FP RTN circuit to FPDM
Open or shorted circuit in the fuel pump
Locked fuel pump rotor
Damaged FPDM
The FPDM sends a 75% duty cycle (750 msec ON, 250 msec OFF) through the FPM circuit to the PCM while the fault is being detected by the FPDM. If the fault is no longer detected, the PCM will return to sending an "all OK" (50% duty cycle) message to the PCM. The PCM will keep P1237 stored in Continuous Memory.
The FPDM controls pump speed by supplying a "variable" ground on the RTN circuit.