[FreedomOne]

4k miles. P0191 OBD-II Trouble Code: Fuel Rail Pressure Sensor Circuit Range/Performance

Joined the club, out of nowhere threw this code. Straight into limp mode on the highway. It was unpleasant. Searching this seems somewhat common over the years. Luckily I was a few miles from the house so it's in the garage.

Thoughts?

 

[FreedomOne]

So I'm out of limp and ecm passed the test on startup which not sure if I'm happy about or not as a ghost issue is more worrisome.
Lift pump pressure is 60
FRPa is within 10-50 of commanded.
Frp1 voltage 1.03
Frp2 voltage 3.97

I sure if that voltage difference is an issue but I think that is throttle dependant as above was at idle.

Maybe a connection issue on frp sensor? No other related engine codes.

 

[FreedomOne]

Seems like there are multiple scenarios and fixes for this but this gm tech link article did pop up.

Damaged Fuel Pressure Sensor Connector – TechLink

 

[viper8315]

Do you have a Derringer?

 

[FreedomOne]

Do you have a Derringer?

Yes, was running stock setting all day though.

 

[viper8315]

I had the same problem a month ago. Called Banks and they sent me a new Derringer.

Even in stock setting, the Derringer is still intercepting the signal.

If you do call Banks, make sure they send you a new Derringer and harness. A month after replacing the Derringer, I got another limp mode for the MAP. It was either a dirty MAP sensor or flakey harness.

Also, do you have an iDash?

 

[FreedomOne]

I had the same problem a month ago. Called Banks and they sent me a new Derringer.

Even in stock setting, the Derringer is still intercepting the signal.

If you do call Banks, make sure they send you a new Derringer and harness. A month after replacing the Derringer, I got another limp mode for the MAP. It was either a dirty MAP sensor or flakey harness.

Also, do you have an iDash?

Yes, running the idash as well but the idash wouldn't read the code. Used a obd link mx+ adapter once I got home. Was yours the same code? I'm hesitant to blame it on the Derringer as this code seems vague in its fixes from looking at the multitude of post on it.

 

[viper8315]

Yes, it was the same exact code. After you tell the iDash to read the code, you have to scroll down to see it, unless the iDash said "no codes".
In my talks with Banks, it's also important that the iDash wakes up when you start the truck. The Derringer gets it's main power from the iDash. If the iDash is asleep, the Derringer is also asleep and in "safety bypass mode"

 

[FreedomOne]

Yes, it was the same exact code. After you tell the iDash to read the code, you have to scroll down to see it, unless the iDash said "no codes".
In my talks with Banks, it's also important that the iDash wakes up when you start the truck. The Derringer gets it's main power from the iDash. If the iDash is asleep, the Derringer is also asleep and in "safety bypass mode"

Idash screen was blank, never showed anything which was weird when I tried to check the code. And yes I've had intermittent issues with the idash not waking up.

 

[viper8315]

Well, granted, your TSB that you found is interesting, but it was probably the Derringer. Is your iDash and Derringer up to date with the latest firmware?

Also, when I spoke with them, sometimes the iDash update doesn't fully "take". Here's what they suggested...
1. Save all settings to the SD card
2. Update iDash
3. Factory reset iDash
4. Recall saved settings

If you have already updated your iDash to the latest firmware, then skip step 2 in the above procedure. They definitely tweaked the "wake up" routine in the newer firmware. With that said, my iDash still doesn't wake up sometimes. You just have to push any of the buttons to wake it up.

 

[FreedomOne]

Well, granted, your TSB that you found is interesting, but it was probably the Derringer. Is your iDash and Derringer up to date with the latest firmware?

Also, when I spoke with them, sometimes the iDash update doesn't fully "take". Here's what they suggested...
1. Save all settings to the SD card
2. Update iDash
3. Factory reset iDash
4. Recall saved settings

If you have already updated your iDash to the latest firmware, then skip step 2 in the above procedure. They definitely tweaked the "wake up" routine in the newer firmware. With that said, my iDash still doesn't wake up sometimes. You just have to push any of the buttons to wake it up.

Updated a couple weeks ago. I'll check all the connections and reset the idash. Also found this to support your theory.
My Son, and The Banks Derringer

 

[viper8315]

I found that exact same post during my issues.
Try doing a recall last code on your iDash. See if you get anything. If you do, take a couple pics of the data, I want to compare what happened to me.

 

[Ottowood]

Seems like there are multiple scenarios and fixes for this but this gm tech link article did pop up.

Damaged Fuel Pressure Sensor Connector – TechLink

I have replaced many of these connectors..
The replacement connector is an updated version..

Here you can see it..
I would replace it with the new one to be sure it's not a problem..

 

[FreedomOne]

I have replaced many of these connectors..
The replacement connector is an updated version..
View attachment 1086468
Here you can see it..
I would replace it with the new one to be sure it's not a problem..

Do you know the part number for that connector? Thanks for the info.

 

[FreedomOne]

Bulletin No.: 20-NA-197 September, 2020 Page 3
Parts Information
Causal
Part
Description Part
Number
Qty
N/A CONNECTOR,
WRG HARN 19367009 1
N/A
ACDelco
Dielectric
Lubricant*
12377900
(U.S.)
10953529
(Canada)
1
*There is enough material to do additional vehicles. Store
the remaining material for future use.
Warranty Information
For vehicles repaired under warranty, use:
Labor Operation Description Labor Time
5430860 Connector Kit Replacement Use the Published Labor
Operations Time
Version 1
Modified Released September 23, 2020

Looking up that part number it looks like the old blue connector but that could be old stock or old photo.

Correct photo with part.
Connector Kit 19367009 | GM Parts Center

 

[Ottowood]

Yes.. 19367009..

 

[viper8315]

@Ottowood , thanks for the advice.

By any chance, have you seen anything similar with the MAP sensor connector?

 

[Ottowood]

@Ottowood , thanks for the advice.

By any chance, have you seen anything similar with the MAP sensor connector?

No sir..
Nothing for the MAP..

 

[viper8315]

Thanks, I had two different codes (and limp modes) within a month of each other. First, was same as the OP for the FPR. Second, was for the MAP.
New Derringer and new Derringer harness... we'll see what happens.

 

[Ottowood]

Make sure your MAP sensor is clean..