P0087 + P0088 Fuel Rail Pressure Too Low/Too High
 

My 06 S Type V6 would not down shift and accelerate quickly, it would sputter. Shortly after, my check engine light came on and threw a 0087 and 0088 meaning

0087: Fuel Rail Pressure Too LOW
0088: Fuel Rail Pressure Too HIGH

Anyone seen this? Any ideas?

I looked on my JTIS CD (which covers through the 2004 model year for the S-Type) but I see no listing or description for code P0087 or code P0088. My CD shows P0058 and then does not show another code until P0096. Perhaps your particular codes did not come into existence until after the 2004 model year. Sorry I couldn't be of any more help to you....

jacob, sounds like to me that your fuel pressure regulator is sticking, therefore driving your fuel pressures all over the place. This can be confirmed by connecting up a fuel pressure gauge to the vehicle and then placing the ignition key in the RUN position. If the motor is running, you should see a steady 30-40 psig. If the motor is not running, then you should be up in the 40-50 psig range.

if you need more info, let me know and I will do what I can help. There is a valve on the fuel rail (normally) that you can connect the gauge to to read out the pressure. just make sure to bleed off the pressure before disconnecting or you can squirt some gas here and there.

could the sub freezing temps here in Dallas (in the 20s) have anything to do with it? I know gas won't freeze at that temp, but just thought I'd throw that out there.

also, the check engine light went away after a few drives of the car, but I'm still having the same performance issue.

thanks Thermo!!!

Clearly it could be a failing fuel pressure sensor, but it could be something else that's then upsetting the PCM. Did the freeze frame data help? What was it? Especially, what were: VSS (speed), RPM and the fuel trims?

If the DTCs have gone without you clearing them, the problem would appear to be intermittent. Starts to sound like the sensor or a wiring problem.

But if the DTCs have gone as above then it shouldn't have a performance issue.... yet it does. Very odd. Anything about the car's history that may matter? You know: been crashed, badly serviced, surprisingly high mileage, odd noises.... well, anything unusual or noteworthy?

If you do measure fuel pressure, I think it'll jump around a bit as it's a returnless system. Not sure what to expect. You can also read it using OBD. Worth recording and trying to reproduce the freeze frame conditions to see if the fault is repeatable.

Keep an eye out for anything else odd, just in case it could be a failing battery. They create some w-e-i-r-d symptoms!

Hi i'v only had the car for a few months and this code has come up (P0087) which i now know means low fuel pressure! I was told the car had all new filters in when I got it but have since found the air filter looked about 10 yrs old, could the fuel filter be the trouble? also where about's on the engine is the fuel rail pressure sensor??
Thanks for any help
Ken

In my case it was a bad fuel pump. It was pretty obvious due to the codes and sputtering of the engine at high revs. Pump was about $300 and my buddy works for Jag so labor was free :)

j