Td4 - P1190 - Fuel Rail Pressure Plausibility

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DreameD
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Td4 - P1190 - Fuel Rail Pressure Plausibility

Post by DreameD »

the current is 0.71 at idle, but under load varies.... One time, just before car broke down in traffic, regulator current showed 4+ and then engine died. Almost like a struggle to increase pressure? I can see the readings of the regulator are quite random when I rev the engine sharply and rapidly (stationary). Sometimes it goes 2+... sometimes 4+ under relatively same pedal load. This brings me to another possibility which is throttle response. Pedal Demand readings seem very random. Sometimes I press the pedal sharply and the diagnostic doesn't show any load.

I really hope it's not the HP pump. How can I test regulator with a multimeter? Or if I take the regulator out, how can I tell if it's broken? Also how can I test if the rail sensor is broken/accurate? Car works fine without it....a bit under powered of course but at least no rattle.

Any help sooo much appreciated!! I've been dealing with this for some time and have no idea what can be wrong. And how can I test what is broken....
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Hi guys!

Hippo needs rescue. Please help!

Freelander 2004, BMW M47R, TD4, 2.0l manual. 93k. Bosch Fuel Rail.

I keep getting the same code P1190- Fuel Rail Pressure Plausibility. Car starts limping/engine rattles/knocks usually in second and third gear around 2k revs +/- . Idle is fine 100%. Fault usually occurs in very close response to throttle demand (it can happen if I let go of pedal abruptly for example at 3k revs and by the time it reaches 2k and I accelerate again it starts limping)

I tried many things already, cleared the code, but so far it keeps coming back when I go for a ride..... UNLESS I disconnect the fuel rail pressure sensor. Without the sensor connected the car doesn't limp and engine doesn't rattle under load any more. So the fault is given by the HIgh Pressure sensor.

Code comes with MAF disconnected for example. Injectors are fine. LP and filter replaced.

I get live readings of 350+Kpa for LP and 26k+ at idle for HP pump (but fluctuating to 28k) and goes up to 120k under load.

Can't go past 3k revs in 5th gear, 70MPH. Unless downhill.

I have videos if you need more evidence. But maybe you guys can explain why car doesn't rattle when fuel pressure sensor is disconnected. I checked the rail cables. They have 5v and 0.5v return at ignition. The loom has been replaced a few years back.

Another culprit can be the Rail pressure regulator----> the current is 0.71 at idle, but under load varies.... One time, just before car broke down in traffic, regulator current showed 4+ and then engine died. Almost like a struggle to increase pressure? I can see the readings of the regulator are quite random when I rev the engine sharply and rapidly (stationary). Sometimes it goes 2+... sometimes 4+ under relatively same pedal load. This brings me to another possibility which is throttle response. Pedal Demand readings seem very random. Sometimes I press the pedal sharply and the diagnostic doesn't show any load.

I really hope it's not the HP pump. How can I test regulator with a multimeter? Or if I take the regulator out, how can I tell if it's broken? Also how can I test if the rail sensor is broken/accurate? Car works fine without it....a bit under powered of course but at least no rattle.

Any help sooo much appreciated!! I've been dealing with this for some time and have no idea what can be wrong. And how can I test what is broken....