Ford Mustang Forum banner

Cobra Jet Install/Error Codes

671 Views 7 Replies 3 Participants Last post by  5ohmatt
So I installed a Cobra Jet setup (Ported CJ, Ported twin 69 TB with harness, P-51 CJ Intake) on my 2018 Mustang GT, install seemed to go fine, followed all same steps from my friends car when we did his but when we attempted to start the car the car starts up then dies off, we unplugged the MAF sensor and car would start up and stay idling fine. We double checked all lines, connected the MAF again got another base file from tuner, car started up, rpms flicker up and down, drives, but really no power behind it, still throwing the same exact code. The Code is P0193 "Fuel Rail Pressure Sensor "A" Circuit High. Does anyone have any ideas or explanation what I need to do from here to get rid of this code? The Tuner I am using is Tricky Performance.
Below is a picture of the code.


See less See more
1 - 3 of 8 Posts
The PCM will put the car into limp mode if it detects a problem like this in the FRPS(fuel rail pressure sensor) circuit. You probably either damaged the wiring harness feeding it or the sensor itself. If the wiring and connector look ok going to the FRPS then just replace the sensor itself. You can verify that the reference voltage at the FRPS is between 4.5 and 5.5 volts with the ignition on and engine off. The PCM or the wiring to it from the FRPS would be the only other possibility however the PCM being defective would be very rare.
Yeah, I know it starts up and runs...
I guess I should have used different terminology when I said "limp" mode. I should have said derate mode which will give a loss of power. Limp mode as it's often called does the same basic thing but is just more extreme. Limp mode would be known as the maximum derate mode that the PCM would implement. You simply aren't in maximum derate but as you just said your RPMs bounce which is a clear indication that the PCM is trying to protect the engine. In any case, it's just semantics and this trouble code will usually make the PCM cut engine power.
As I already said, if it's not the sensor or wiring/connectors then it's something with the PCM. Since you got a new tune then I would look to the tuner who programmed it since it's otherwise probably a bad tune. I don't remember ever hearing of Tricky Performance before this.
See less See more
That was the FRPS connector that I was talking about. This is why I said to check over the wiring to the sensor first.
We all make mistakes but instead of wasting your time it would have been best to check before yanking off engine parts.
1 - 3 of 8 Posts