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hi guys am gettin really annoyed with the car its still cutting out sometimes when driving takes a few turns before it can start now when the you rev the car up black smoke comes from the exhaust any ideas if my injectors are knackered or any ideas what this could be on a diagnostics it showed up fuel rail sensor and fuel pump

hi mate what engine is it?

I assume its diesel - if the injection ecu detects a single faulty injector it will stop the engine so it only needs one bad one to take the engine down.

Wrong rail pressure will also cause an error that can result in an engine stop. The fuel pressure must be above 120 bar in the rail at all times or injection will be discontinued by the injection ecu, but low fuel pressure would normally not cause smoke. Black smoke is excess fuel, or not enough airflow (clogged air filter) or bad EGR valve perhaps, but you need to give more details about the car, and what led up to this etc or we are just guessing...

sorry mate its a 2.0l hdi 110 diesel its done 110000 miles
the car cuts out aff i have gave it a good drive and when ive applied alot of revs could it be possible that the fuel rail sensor is sending my ecu the wrong reading as the diagnostics showed up fuel rail sensor fault any ideas how much this would cost

have you checked your turbo pipe work especially near to the intercooler ??

they are cheap actually, here is one on evilbay:

http://cgi.ebay.co.uk/Peugeot-Citroen-H ... 2a073a9d42

Its very possible that the sensor is falsely reporting low rail pressure, which would cause the pump (via the electronic regulator) to try and reach its target value - perhaps going overpressure and causing smoke from increased injection volume, or the excess pressure keeping the injector needles open too long - by resisting the solenoid valve in the injector head from closing under its return spring force, this would show up as increased leak-back too.

If the sensor reports less than 120 bar the injection ecu will stop the injection sequence and it will cut out, could be your problem indeed. especially when you have a rail sensor error code, but check the wiring etc before swapping it, and leave at least 30secs after running the engine before you slacken the old one to let the pressure subside to zero in the rail if you end up changing the sensor.

To test the sensor (Bosch) the middle pin should read 0.5v ign on; 1.2v at idle and 1.8v at 3000rpm and steady 5v across the outer pair.

If the actual pressure regulator on the pump is faulty, then these are not cheap but an o-ring kit can be had for it instead of replacement, just in case the sensor isn't the problem - though I think it may well be.

As Puggy says, if you have a boost leak, that would cause smoke but likely not a pressure sensor error.

thanks mate uve been alot of help going to replace this and then continue from there i got rid of black smoke wasnt much but was noticeable on my driveway i put redex through the system and it seemed to have worked so just the sensor now well keep you updated thanks again

good one mate, hope it clears.

If anyone is interested, asda sell redex (petrol AND diesel version) for £3.49!!!

Half garage price.....