CEL P0190 - Fuel Rail Pressure Sensor Malfunction: Input

0949er · 10-22-2009, 07:35 PM

Quote:

P0190 - Fuel Rail Pressure Sensor Circuit Malfunction (FRP)

The comprehensive component monitor (CCM) monitors the FRP sensor to the PCM for VREF voltage. The test fails when the VREF voltage from the PCM drops to a voltage less than a minimum calibrated value.

* VREF open in harness.
* VREF open in sensor.
* VREF open in PCM.

Verify VREF voltage between 4.0 and 6.0V.

My roommate and I love cars, and when I was leaving today for class (he was standing outside) I decided to give it a lil rev about 2-3 seconds after I turned the car on (car WAS WARM, was only home for about 30 min)

well, after I did it, as I was driving away, (I wasnt burning out or anything, just a simple rev and that was it) I noticed that my CEL came on. Went to class, figured it would clear if i let the car sit for an hour or so. Nope. So after class took it to auto-zone and that is what it read.

Guy suggested: (based on the references he found on his computer at autozone)

fuel Pressure low- fuel pump defective
fuel pressure regulator defective
replace fuel filter
replace fuel rail pressure sensor

I told him I would check with the pro's on MustangForums.com haha. Anyways, anybody run into this before? Car has 43k miles. I have not changed anything since I have bought the car, except oil (every 3k miles)

And with the car having almost 50k miles, what are the usual maintenance problems I should be addressing as my car approaches over the hill? haha.

thanks guys.

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0949er · 10-22-2009, 07:42 PM

ok after searching some on the forums, it looks like most people who post this also say there car is running poorly, (starting/stoping, not starting, etc). however, this is NOT the car for me. The car itself runs perfectly. Good idle, does not fluctuate at idle, nothin. So Im curious on your guys input.

First things first, I think I will try the "fuel filter" approach... considering I have never changed it

mustangman03 · 10-22-2009, 07:56 PM

I would try a fuel filter that would cause low fuel press. and it is a lot easier and cheaper to put on than a fuel pump i dont beleave it would be the sensor.

Xemeth · 10-22-2009, 08:05 PM

Quote:

Originally Posted by mustangman03

I would try a fuel filter that would cause low fuel press. and it is a lot easier and cheaper to put on than a fuel pump i dont beleave it would be the sensor.

Why not? If the sensor is sending incorrect information to the PCM, then it will set the code. He could have no actual problem, minus the sensor being bad.

OP, change the fuel filter, since it's routine maintenence anyway. Then have the code cleared, and if it comes back, change the sensor. I doubt you actually have low fuel pressure. When the pressure is low, you usually have extended crank time or the car won't start at all (if it's low enough).

cliffyk · 10-22-2009, 08:27 PM

Here's what the Ford shop manual has to say--none of which have anything to do with fuel pressure, fuel filters, or fuel pressure sensors.

I'd clear the DTC, not "rev" the engine for no purpose in the future, and check the battery and alternator for proper capacity/operation...

0949er · 10-22-2009, 08:48 PM

Quote:

Originally Posted by cliffyk

Here's what the Ford shop manual has to say--none of which have anything to do with fuel pressure, fuel filters, or fuel pressure sensors.

I'd clear the DTC, not "rev" the engine for no purpose in the future, and check the battery and alternator for proper capacity/operation...

should I un-plug the battery for a while or should I clear it with a hand held (you can do that right?)?

also, what will the the effects of a "reboot" like that, considering I have a tune? would anything happen?

cliffyk · 10-22-2009, 09:12 PM

You cannot clear a recorded DTC by disconnecting the battery, it has to be cleared by using a scantool to send a mode 04 "request" to the PCM,

Beyond that, disconnectimg the battery will not have any effect on you custom tune, the stock tune, or any other tune--all it will do is clear the KAM (Keep Alive Memory) where things like idle air trim, short and long term fuel trim, and other "learned" parameters are stored--causing the PCM to relearn same.

In fact, an argument could be made for resetting the KAM 3 to 4 times a year as the seasons change,,,

Frostbitten · 10-23-2009, 01:27 AM

its the fuel pump, i have run my car for days with a broken fuel line and didnt even know it. took it to the dyno and was suprised to see it was only holding 22psi

0949er · 10-23-2009, 12:05 PM

so can I replace my current Fuel pump with this:

http://cgi.ebay.com/ebaymotors/Svt-F...Q5fAccessories

considering that I am in the process of getting my car ready for the vortech?

jwog666 · 10-23-2009, 04:40 PM

i have changed a few frp sensors for this code. they go bad internally and dont deliver the 5v ref signal to the pcm, and bingo the cel is on. do not change your fuel pump unless you like wasting money.