Thread: Breakdown - P0191 Fuel Rail Pressure Sensor

You might get lucky with a rail pressure sensor. That code you read should have a dash number p0910-23 example. The dash number relates to the type of failure. Example voltage above threshold etc

1. pretty sure this is the fuel sensor worth changing at approx $100 ex UK but they come in two thread types thin and thicker apparently so in order to order a new one i needed to remove my old one. removed all bits n pieces for better access.

2. spanner does not fit, tried all types of spanners but the closest is this 1/2 inch which is still not the correct size, that damn nut is so tight unable to move it at all.

packed up for today will look at it tomorrow, need a diff size spanner yet thin enough to give me access. any suggestions please

That spanner is 1/2 Whitworth, which from memory is about 19mm . Yes they are tight they are generally a tapered thread for fuel rail pressure. Like npt air lines. They usually put a bit of high pressure sealant on them in the factory which sets better then super glue

Originally Posted by josh.huber

That spanner is 1/2 Whitworth, which from memory is about 19mm . Yes they are tight they are generally a tapered thread for fuel rail pressure. Like npt air lines. They usually put a bit of high pressure sealant on them in the factory which sets better then super glue

Best place to find Whitworth spanners is the local markets.
They are difficult to get from the usual places at times.

The size will be metric, not Whitworth and that spanner has been modified so the Whitworth size isn't much of a guide.

1. got the hammer and chisel onto it this morning and managed to get it out that way. finally... funny thing is there was no fuel (diesel) pouring out of this opening surely the rail should be full of diesel and some should of poured out. thinking now might be another issue such as the low press fuel pump in the tank but have ordered a new sensor to try that first from the UK

2. said sensor come in two diff thread sizes this is the thicker thread 55PP19-02 the other one fitted are the 55PP19-01 which has the thinner thread. Now to wait for the replacement part to arrive from Uk approx $130 and see if this solves my problem or whether i need to drop the tank.

i could crank her over to see if diesel squirts out of the remaining hole where the sensor fits, that should tell me if the intank pump works or not?

Just tested by cranking over the engine, only a very small amount of diesel came out of the sensor opening, i would of thought this should be under immense pressure and diesel would squirt everywhere but it didn't so not sure what to make of this, whether that's normal or i have a faulty pump in the tank or another issue blocking fuel supply to the rail.

There is a shraeder valve on top of the engine. You can put an improvised gauge on there. I suggest buying the manual to find out required pressures.