Vauxhall Opel Astra 2.0 Diesel 2012

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Iver
TwoWaves
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Vauxhall Opel Astra 2.0 Diesel 2012

Post by Iver »

Vauxhall Opel Astra 2.0 D
Engine Starts for a few seconds then dies
Fuel Pressure Rises to 1800 Bar

New MPROP / IMV Fitted
ECU Replaced but Software Cloned From Original ECU

I'm not too sure what to make of this, I can see that the ECU is not trying to control the IMV !

I was thinking this should have a Permanent 12v and PWM Earth - Perhaps some can confirm this ?

The one thing I have not done is Load test the 2 wires to the MPROP / IMV, just thought about that now.

You can see from the Fuel Pressure Sensor waveform the pressure build, the engine runs for a few seconds and cuts out.

Channel A & B Mprop
Channel C Fuel Pressure Sensor
Channel D Mprop Current

Can any one help ?
Attachments
Astra 2.0 D.psdata
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Tomblueprintauto
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Re: Vauxhall Opel Astra 2.0 Diesel 2012

Post by Tomblueprintauto »

Are you thinking 1800 bar is too low? I'd have thought that was enough to run.
That drop in fuel pressure, is that after it dies or before?

Can you get waveform with cam or crank, injector pulses and fuel pressure?

picowight
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Re: Vauxhall Opel Astra 2.0 Diesel 2012

Post by picowight »

Looking at the waveform if A is +ve supply to IMV and B is the PWM control then you are loosing the 12v to the IMV the moment current flows. Your average of 800ma seems way too low.

If you measure V on that line with a DVM it will tell you B+ no problem, but put a 2A test light on it and it will not light and the voltage will disappear.
I suspect if you check the wiring diagram you should be able to give a (fused!) 12v to that line and expect to see the car run. The ECU is shutting it down when it realises that it can not control the fuel pressure.
Screenshot from 2022-09-15 22-06-19.png
Also the ECU is trying to control the IMV, I added a maths channel for the -ve duty of the IMV control and you can see the ECU puts it up to almost 100% as the FRP rises- not sure about the wiggle in the middle - probably ECU attempting to unstick a solenoid, or it might just be from the low battery
Screenshot from 2022-09-15 22-22-43.png

Iver
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Re: Vauxhall Opel Astra 2.0 Diesel 2012

Post by Iver »

picowight wrote:
Thu Sep 15, 2022 9:17 pm

I suspect if you check the wiring diagram you should be able to give a (fused!) 12v to that line and expect to see the car run. The ECU is shutting it down when it realises that it can not control the fuel pressure.

Also the ECU is trying to control the IMV, I added a maths channel for the -ve duty of the IMV control and you can see the ECU puts it up to almost 100% as the FRP rises-
Thank you, i looked again at the PWM of the IMV and indeed it appears the ECU is trying to control it.

It is fixed now :D

High resistance in power supply to ECU, It has 4 B+ supplies, just one had failed. Both the B+ and switche
I suspect if you check the wiring diagram you should be able to give a (fused!) 12v to that line and expect to see the car run.
I tried that and it would not run, exactly the same !! that is possibly made me look at ECU power supply
Last edited by Iver on Thu Sep 22, 2022 9:29 pm, edited 2 times in total.

Iver
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Re: Vauxhall Opel Astra 2.0 Diesel 2012

Post by Iver »

Tomblueprintauto wrote:
Thu Sep 15, 2022 8:47 pm
Are you thinking 1800 bar is too low? I'd have thought that was enough to run.
That drop in fuel pressure, is that after it dies or before?
I'm thinking 1800 bar is way too much at idle, enough to stop the engine for safety reasons. I'm guessing it may continue to rise un controlled.

I would expect a Max of about 350 bar at idle.

The drop in FRP is after it dies and the pump stops rotating.

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