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Duratorq 2.0 D, FRP sensor 5v ref
Duratorq 2.0 D, FRP sensor 5v ref
06 Jag xtype 2.0 D- Intermittent cut out at load when hot -I wont bore you with the history of parts darts and diag on it.
I backprobed into the +5v ref on the Fuel rail Pressure sensor and held it at high revs for a while (the standard rail pressure test had been nominal), after a short while held at 3.5k with the engine hot I started to see the power appear to drop out. Thinking it had maybe shook the backprobe loose I did it again and got it to repeat - saving it this time. - As I could not get it to do it a 3rd time when probed at the ECU and ran out of time I am now doubting what I saw.
I will get back to it but would like a second opinion please - dying sensor or bad probe connection ?
I backprobed into the +5v ref on the Fuel rail Pressure sensor and held it at high revs for a while (the standard rail pressure test had been nominal), after a short while held at 3.5k with the engine hot I started to see the power appear to drop out. Thinking it had maybe shook the backprobe loose I did it again and got it to repeat - saving it this time. - As I could not get it to do it a 3rd time when probed at the ECU and ran out of time I am now doubting what I saw.
I will get back to it but would like a second opinion please - dying sensor or bad probe connection ?
- Attachments
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- FP SENSOR POWER.psdata
- (83.76 KiB) Downloaded 310 times
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Re: Duratorq 2.0 D, FRP sensor 5v ref
Not familiar with this engine but I would won’t to see the control side of the fuel rail pressure and verify upstream of the sensor is not influencing your trace, I would agree it appears that the signal is dropping out.
Does it have any audible or visual indication of fuel pressure actually dropping out?
Does it have any audible or visual indication of fuel pressure actually dropping out?
Re: Duratorq 2.0 D, FRP sensor 5v ref
Thanks muttnjeff
I felt at the time that the car had started to stumble/missfire when I was seeing the drop outs, but then when i added a probe to the ECU end of the 5v ref wire, when I felt the car stumbled the same I did not see the drops on either channel.- So yes and no!
The fault is intermittent and originally thought random, but now repeatable (faked heavy load driving - low speed, hill, high gear, and thoroughly hot) so that rules out a random dodgy connection. Only after a few hours of heat up did it develop any symptoms stationary - smoke and stumble at high rpm.
There is a good clean 12v PWM signal to the (new) IMV and a current clamp shows draw in line with the control signal.
Going to get the car thoroughly hot and start over on the fuel system tests - starting with that 5v ref for the FRP sensor - if that 5v ref trace is real I've got it - if it was a coincidental loose probe (twice) I haven't
I felt at the time that the car had started to stumble/missfire when I was seeing the drop outs, but then when i added a probe to the ECU end of the 5v ref wire, when I felt the car stumbled the same I did not see the drops on either channel.- So yes and no!
The fault is intermittent and originally thought random, but now repeatable (faked heavy load driving - low speed, hill, high gear, and thoroughly hot) so that rules out a random dodgy connection. Only after a few hours of heat up did it develop any symptoms stationary - smoke and stumble at high rpm.
There is a good clean 12v PWM signal to the (new) IMV and a current clamp shows draw in line with the control signal.
Going to get the car thoroughly hot and start over on the fuel system tests - starting with that 5v ref for the FRP sensor - if that 5v ref trace is real I've got it - if it was a coincidental loose probe (twice) I haven't