My 2008 Peugeot 207cc 1.6 HDi has a weird fueling issue so I thought I'd have a quick look with DiagBox to make sure the injectors are coded correctly.
While in there I did a live test on the four 'Injector Flow Correction' values.
Not too sure what I'm looking at but 3 of the injectors have what seem to be sensible values in the 0 to 2 range, but injector 2 is returning 'Value Invalid' and is flat lining at 6.
Does anybody have any idea what this means?
Invalid injector correction value
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freddyokel
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Invalid injector correction value
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freddyokel
- (Donor 2025)
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Re: Invalid injector correction value
I'm guessing this means the ECU is pushing an extra 6mg per squirt into injector 2 (at idle!) which is then just coming straight back out of the low pressure return.
My leak back test kit arrives soon so I'm suspecting this will confirm that I might need to replace injector 2...
My leak back test kit arrives soon so I'm suspecting this will confirm that I might need to replace injector 2...
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freddyokel
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Re: Invalid injector correction value
Now I've learned that the '6' is a reduction. So the ECU is almost shutting down injector 2 at idle as it's leaking so much back to the low pressure return (detected by a lowering of rail pressure maybe)
Gonna do the leak back test tomorrow and I suspect it may be dramatic.
Gonna do the leak back test tomorrow and I suspect it may be dramatic.
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Rp0thejester
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Re: Invalid injector correction value
Keep us posted
Ryan
'99 Xsara 1.6 X (Red) with Sunkissed bonnet. T59 SBX
'54 Astra Estate 1.7DTI (Artic White)
'06 C8 2.2Hdi Exclusive (Aster Grey)
Champion of Where's CitroJim
Yes I ask the stupid questions, because normally it is that simple.
'99 Xsara 1.6 X (Red) with Sunkissed bonnet. T59 SBX
'54 Astra Estate 1.7DTI (Artic White)
'06 C8 2.2Hdi Exclusive (Aster Grey)
Champion of Where's CitroJim
Yes I ask the stupid questions, because normally it is that simple.
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freddyokel
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Re: Invalid injector correction value
Car has just returned an almost perfect leak back test. Urgh...
So why no smoke?
Only thing I can think of is that the heavy negative adjustment at idle is compensating for the a leak which goes away under pressure. So... leaking pilot jet?
But is this enough to cause the P0087 after 3000rpm which is the main problem?
Or... is this injector weirdness a separate problem?
I'm pretty much learning common rail diagnosis on the fly here...
So why no smoke?
Only thing I can think of is that the heavy negative adjustment at idle is compensating for the a leak which goes away under pressure. So... leaking pilot jet?
But is this enough to cause the P0087 after 3000rpm which is the main problem?
Or... is this injector weirdness a separate problem?
I'm pretty much learning common rail diagnosis on the fly here...
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viva3200
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Re: Invalid injector correction value
Hi freddyokel.
I have this problem. I changed the injector on cylinder 2, but there was no change. I don't know what to think anymore?!
Was the problem solved for you?
Best regards
I have this problem. I changed the injector on cylinder 2, but there was no change. I don't know what to think anymore?!
Was the problem solved for you?
Best regards
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freddyokel
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Re: Invalid injector correction value
For a while I was convinced that what the ECU was saying was wrong.
But... I disconnected the battery (to replace the fuel filter) and after around 20 minutes off, it would appear that the ECU forgot the correction values.
The engine ran rough, like a misfiring petrol for a few minutes until it gradually became smooth again.
When it stops raining and I have time I'm going to disconnect the battery again and run a leak back test while it's running lumpy. I'll also monitor the correction values to see if it's actually 'relearning'.
So, replacing injector 2. Are you sure you've replaced the right injector? PSA cars number from the gearbox end and not from the cambelt end.
But... I disconnected the battery (to replace the fuel filter) and after around 20 minutes off, it would appear that the ECU forgot the correction values.
The engine ran rough, like a misfiring petrol for a few minutes until it gradually became smooth again.
When it stops raining and I have time I'm going to disconnect the battery again and run a leak back test while it's running lumpy. I'll also monitor the correction values to see if it's actually 'relearning'.
So, replacing injector 2. Are you sure you've replaced the right injector? PSA cars number from the gearbox end and not from the cambelt end.
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freddyokel
- (Donor 2025)
- Posts: 77
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Re: Invalid injector correction value
Sorry to necrothread, but I said I'd keep people updated.
Finally took it for a run with Diagbox running.
Seems our +6mg (if that IS what it means) injector tails off to normal at mid-range load, but then starts to head the other way.
When it hits the -6mg limit, (at high load/rpm), the fuel pressure flatlines at 1250 bar so I suspect that's the limiting factor.
Ultimately injector 2 (and being PSA, that's the second injector from the GEARBOX end) is knackered. But it works in mid-range and the ECU is compensating at idle.
Finally took it for a run with Diagbox running.
Seems our +6mg (if that IS what it means) injector tails off to normal at mid-range load, but then starts to head the other way.
When it hits the -6mg limit, (at high load/rpm), the fuel pressure flatlines at 1250 bar so I suspect that's the limiting factor.
Ultimately injector 2 (and being PSA, that's the second injector from the GEARBOX end) is knackered. But it works in mid-range and the ECU is compensating at idle.