P1191 Opel Vectra Z22YH engine

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Dave Hill
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Re: P1191 Opel Vectra Z22YH engine

Post by Dave Hill »

Hi Bjorn

Let me know if you need any assistance hosting the Pico psdata files (if they are too large for the forum). I can host them on my website server space & provide you with the download links.

:)

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Tronic
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Re: P1191 Opel Vectra Z22YH engine

Post by Tronic »

Hi Dave and thanks for your kind offer! :)

I will do so Dave! As I see, at least one of the psdata files exceed 20MB so it may not be possible to upload them here. Meanwhile, when students are gone for the 2 coming weeks and until the tests with RPS and RPR takes place, It would be interesting to get some input whether the low pressure pump waveforms taken with WPS500 could be used, in some way, to interpret if the high pressure pump is doing its job properly in our GDI engine. Forgive me if it sounds stupid, it is just my thoughts and may not even be close to reality. :oops:

Thanks Dave!

Bjorn

Dave Hill
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Re: P1191 Opel Vectra Z22YH engine

Post by Dave Hill »

Hi Bjorn

File size limits can be frustrating, but there are things that you can do to help your cause. Pico Kev has just made the point on another recent post, where he shows how you can reduce the saved file size, by simply selecting the single "current" waveform, rather than all of the buffered screens.

as an alternative to hosting them on the forum directly, there are other options available, in the form of such services as Mega & perhaps Google Drive.


If you have a Googlemail email account, then you almost certainly have a 15 GB storage facility, which allows you to upload most files & then you can generate a link to the file. This link can then add to your forum post & folks can then download it directly from your Google Drive.

Mega is a very useful storage facility too. >>> https://mega.co.nz/

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Tronic
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Re: P1191 Opel Vectra Z22YH engine

Post by Tronic »

Hi again Dave and thanks for excellent information!

I made an account at Mega. Lets see now ... here is one of my tests containing 9 frames with RPR, RPS, 5V supply RPS and LP fuel pump, but there are more. Just a test to see if it works!

https://mega.nz/#!8VUF3Y6b!smgCFzH8FgmI ... 7gvrkyvdIE


Bjorn

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Re: P1191 Opel Vectra Z22YH engine

Post by STC »

Hi Bjorn.

Frame 8 & 9 of your capture are of Diagnostic Interest. I have added a Math Channel to the Rail Pressure Regulator to show Percentage Duty Cycle - Green Line.
Frame 8 - Rail Pressure And Regulator Command
Frame 8 - Rail Pressure And Regulator Command
Frame 9 - Rail Pressure And Regulator Command
Frame 9 - Rail Pressure And Regulator Command

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Tronic
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Re: P1191 Opel Vectra Z22YH engine

Post by Tronic »

Thanks STC for taking your time to look at my psdata file!

You made it easy to see the duty cycle by adding the math channel, that is good - thanks STC for doing that! If you zoom right at the rail pressure peak in frame 9 and look att the LP fuel pump curve form, do you have anything to say about that? What are the irregularities(?) (maybe wrong word?) that can be seen? Is that showing the pressure drop on the opening of the inlet to HP pump. At the end of frame 9, when the engine is turned off, the pressure from LP pump rises to roughly 4.8bar and RPS goes down to 600mV. Sorry if I do not understand mechanical side of this system...

Thanks!

Bjorn

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Re: P1191 Opel Vectra Z22YH engine

Post by STC »

the pressure from LP pump rises to roughly 4.8bar and RPS goes down to 600mV.
The 2 parts of that system are somewhat unrelated, you cannot always compare them side by side. You have your WPS measuring LP & the Rail pressure sensor is measuring HP. With the Engine switched off the Electric Pump will be pumping against a "Brick Wall" which explains the momentary rise in LP. Which then drops off as the pump is switched off.
Your HP pressure drops off instantly to 600mV which converted to bar is probably next to nothing because the HP Pump is no longer running.

What is your view on the HP pressure going up in one frame then the opposite way in the next frame with reference to Duty Cycle Command. I would guess that the clue to your fault is right there.

Your LP side as measured with WPS does not look very stable across the complete capture. Might be an idea to confirm / achieve Steady Pressure & Flow on that side first.

Not sure that you can do much more now until you have the car in front of you again.

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Tronic
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Re: P1191 Opel Vectra Z22YH engine

Post by Tronic »

Thanks for the response and clarification STC!

You are right, since I do not have the car, there is nothing more to do other than some left out thoughts that you my answer if you got time to do so.

Well, then I understand what happens at the end of frame 9 when the pressure rises on the LP side as well as the drop on HP side - should have known that. But ... I was also thinking of the LP pump fluctuation and not being stable in my previous post, but did not find right words for it then.

What also caught my eyes was, when zooming right at the pressure peak in frame 9, that there are three peaks and then a heavy drop at LP side and then continue like that with same pattern. First and second peak is just about the same in amplitude, but third is much lower. I am not saying that it has something to do with this particular fault, but I am really curious why this happens. However, there is three pressure peaks which could point to three successively, mechanical movements and shouldn't they be equal in amplitude? I may be far out of how it really works, but it is just an idea I got :lol: Could it mean a faulty HP pump pressure pattern as I believe it has to do with changes in pressure when pump inlet open? Could be, again, far out of reality... Tried to find a data sheet on this Continental HP pump in order to understand how it mechanically works, but to no avail.

Further more, pressure rise for both LP and HP seems to align pretty well and that made me wonder how that could be... Wouldn't a rise on the LP/HP side mean more flow from the LP pump, but ... looking at the wiring diagram for the LP pump circuit that consists of an ordinary pump relay controlled by the ECM, no. There is nothing there that could command an increased fuel delivery. Do not know if my wiring diagram has left out any parts though... Had a couple of more thoughts, but I can not recreate them because I am to tired :|

Thanks STC!

Bjorn

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Re: P1191 Opel Vectra Z22YH engine

Post by Tronic »

Sorry ... one more thing! If you zoom x20 in frame 9 at the pressure peak and look closely at the blue RPS trace, what are these small peaks, 7 in a row in what looks like steps, about 3mS apart? May this show the pressure change derived from modulating the RPR. They doesn't seem to align perfectly though - if you look at on and off time for the RPR... I was also thinking that there could be a small delay for the RPS to response to pressure changes and therefore not be exactly aligned... To long time for being injector firing and there aren't 7 cylinders either... Aaaah! To tired, to much fantasy, good night! :lol:

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Re: P1191 Opel Vectra Z22YH engine

Post by STC »

I think now, at this point that without the car in front of you there could be a real danger of over complicating this. Thinking too hard, too deep with no means of verification.

With the car present you will be able to synchronise with injection events etc. and make judgements as to what is what.
You seem to be ignoring what I pointed out about the HP reacting in opposite directions to Regulator Duty Cycle. That would bother me a lot - just saying.

With the Car, Pico, WPS & PWM Emulator, your limitations will only be your imagination :D :D :D

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