P1191 Opel Vectra Z22YH engine

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Martyn
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Re: P1191 Opel Vectra Z22YH engine

Post by Martyn »

Your first few posts needed approval before they appeared, you have now passed the threshold so posts will appear automatically :D
Martyn
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Tronic
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Re: P1191 Opel Vectra Z22YH engine

Post by Tronic »

Thanks Martyn!

Yes I noticed that, this time it went through with a remarkable speed :lol:

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Tronic
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Re: P1191 Opel Vectra Z22YH engine

Post by Tronic »

Hi all!

I am about to upload both pictures and ps.data files but not sure how to do that. Tried to find "how to"searching the forum, but to no avail. What is the maximum size of a picture, recommended format, size and finally, size of ps.data files. The files will contain some waveforms- concerning this GDI engine - I would like to discuss and I am really interested in what you have to say about them. I can say that It is a matter of interpreting waveforms and of course, achieve greater understanding in what really happens.

Bjorn

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STC
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Re: P1191 Opel Vectra Z22YH engine

Post by STC »

Hi Bjorn

Thanks for the PM

I just looked at the Guided Test Plans, they are online and not so easy to replicate and share. It is a process of conducting a test and then ticking yes or no and then another screen. So a flowchart but not on one page. I have made a promise that I thought would be easier to keep.

To be honest the Guided flowchart is more of a "How NOT to Diagnose the Fault" It is vague and does not assume the use of a scope or PWM Emulator

You can access it here for a small fee https://www.gme-infotech.com/info.html. Before you do check your PM inbox.

As for Posting Pictures and Psdata files, Click on post Reply > Upload Attachment > Browse >> Add the File. You do need to be patient whilst it loads.

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Tronic
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Re: P1191 Opel Vectra Z22YH engine

Post by Tronic »

Hi STC!

Thanks for info on how to upload files. I don´t know if my 22MB ps.data file is to big, but i will try. Seldom using flow charts if they are not a must or they contain info that are unknown to me; find them quiet confusing at times. :lol:

Bjorn

Dave Hill
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Re: P1191 Opel Vectra Z22YH engine

Post by Dave Hill »

This is probably of little use now, but here is my contribution, relevant to this fault code (from the case study library)

https://www.picoauto.com/library/case-s ... 0301-p1191

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STC
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Re: P1191 Opel Vectra Z22YH engine

Post by STC »

Dave
I have read that case study, in fact I have at some point read all of them.

In this particular case, I note that you have compared ECU Duty Command of Pressure regulator against FRP Sensor.

The car is fixed and this is purely academic now, humour me if you will. What I am not getting is why you, with certainty, went for the Pump and not the Regulator on that evidence alone ?

My thoughts being that ECU command of an actuator is no guarantee of it working internally, an amp clamp on the actuator would only show that the electrical element of it is working, the pin that opens and closes the "tap" may well be detached / sheared. Possibly causing it to pull a little less current but I'm guessing nothing conclusive either way.

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Re: P1191 Opel Vectra Z22YH engine

Post by Dave Hill »

Hi STC (your real name would be nice ;-) )

You are correct, in that my analysis of PCM duty cycle command, against rail pressure sensor voltage does nothing more than confirm the corresponding fuel pressure increase does not occur & it reveals nothing about the likely cause.

This is a good while ago now but if I recall correctly, the guided fault finding process referred to a specific TSB (Technical Service Bulletin) which related to this P1191 fault code. Following the TSB guidance, the conclusion was clear.

In the absence of such technical information, it would be normal practice to challenge the components under suspicion, by whatever methods are deemed appropriate & then observe which component falls over.

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Re: P1191 Opel Vectra Z22YH engine

Post by STC »

Hi Dave

Thanks for your reply, indeed if it was a while ago then the finer details can become blurry over time. I have read many articles & posts written by yourself on the net and have, without exception, found them to be Technically Correct and informative.

I didn't pull it up as a criticism or a challenge, just wondered if you knew something that I didn't hence an opportunity to learn something.
This is a good while ago now but if I recall correctly, the guided fault finding process referred to a specific TSB (Technical Service Bulletin) which related to this P1191 fault code. Following the TSB guidance, the conclusion was clear.
In that case I guess that you quite likely did challenge the Rail Pressure Regulator and it was that the Pump that fell over, perhaps that bit accidentally got left out of the case study write up.

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Re: P1191 Opel Vectra Z22YH engine

Post by Dave Hill »

Hi Simon, Steve, Sharon :lol: ....? :?:
STC wrote:
I didn't pull it up as a criticism or a challenge, just wondered if you knew something that I didn't hence an opportunity to learn something.
I didn't take your inquisitive post as a challenge, simply a reasonable request for some more info & I hope that my response didn't suggest anything other.

I don't recall the exact test details, but I don't think there was anything out of the ordinary, or worthy of note. I am away right now, but if anyone needs further information in the form of the TSB or guided fault finding sequences, then I can provide them (off the forum, via pm or email of course)

Thank you for your comments regarding my internet posts. I try to make an effort to make my writing credible, however I am quite open to correction, or discussion, that might advance my understanding of things. Some of my early stuff does expose the steepness of my learning curve at the time. Although it could be quite embarrassing, I am not ashamed of it & I hope that it has inspired some people to have a go themselves.

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