P1191 Opel Vectra Z22YH engine

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Tronic
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P1191 Opel Vectra Z22YH engine

Post by Tronic »

Opel Vectra GDI 2007 2.2l engine Z22YH with P1191 code

Hi all!

This is my very first post on this forum. Work as a teacher in an upper secondary school in northern Sweden. Mostly into electronics but now and then into mechanical stuff, but the latter is not my best side. I thought this was a very good project to show my students how the GDI works, but it was not that easy… Well, I got this Opel Vectra with P1192 code that says low input signal to high pressure sensor which automatically got me thinking of bad supply voltage or maybe a bad ground. The ground was checked showing a good one. Then I hooked up my Pico - files will be upload later - using 4 channels:

Ch1 system voltage (5 volt) at the connector of hp-sensor in order to see if it suddenly dropped.
Ch2 Signal out from hp-sensor.
Ch3 WPS500X attached to schrader valve expecting 4-4,5bar.
Ch4 Regulator on the rail, just to check the PWM command.

I also had a look at the PID´s just to see what pressure was in the rail. It showed around 5000kPa at idle and on a snap nearly 12000kPa which, as I understand, is just about the right figures for this engine. After a couple of snaps the CEL lit up and the rail pressure falls drastically. I have read a lot about this DTC and realize that it is not an easy task to judge which component is the faulty one. Some says that it is the regulator or HP-sensor and some say HP-pump. I do not want to guess, neither do I want to be a part changer so what to do? Is there a good way to accomplish this without swap parts and maybe firstly, start with the HP-sensor? What measurements would you do to point out the faulty part and is my setup a good start? Let me know if there is something you do not understand as I am not a native English speaker. I will put up all files later as soon as I am at the office.

Bjorn

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Tronic
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Re: P1191 Opel Vectra Z22YH engine

Post by Tronic »

Sorry ... maybe my post should be in "Diagnostic discussion"? :oops:

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Re: P1191 Opel Vectra Z22YH engine

Post by Technician »

Are we talking about Common Rail here?

Sorry missed the GDI part.

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Re: P1191 Opel Vectra Z22YH engine

Post by Tronic »

Hi Technician!

Yes, this is an common rail. Tomorrow I will add files recorded on my Pico. I am simply trying to find out how to pick the right faulty component without guessing. :)

Bjorn

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Re: P1191 Opel Vectra Z22YH engine

Post by andrewbishop66 »

Hi
GDI Gas Direct Injection
my suggestion to start would be a variable resister say 10K ohm connected instead of the pressure sensor set the resister so that you get a suitable fuel pressure on the scantool and see if you lose pressure if you still have the problem pressure sensor not likely at fault but I would want to confirm the ground at sensor and sensor output at pcm
and maybe current clamp on the regulator

Have a look here( http://www.bba-reman.com/forums/Topic60947.aspx ) a poster called top bloke listed a number of tests

Thanks Andrew

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Re: P1191 Opel Vectra Z22YH engine

Post by Tronic »

Hi andrewbishop66 and thanks for reply!

That is an good idea! Use to simulate things both here and there, but did not think of that! Excellent! :) I will hook up an potentiometer tomorrow and give it a go and then read the rail pressure. Will also, as you suggested, hook up a current clamp for the FPR. What I did when I first checked it was to see if the duty cycle changed along with snap - and it did. It is late evening in Sweden so next thing to do is to get a good night sleep.

Bjorn

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Re: P1191 Opel Vectra Z22YH engine

Post by STC »

Bjorn,

There are 4 Variations to P1191 and a Technical Service Bulletin

1.
P1191
Fuel Rail Pressure Sensor Circuit Low Input
•Common rail pressure is less than 10000 kPa ( 100 bar )
•Above conditions must be fulfilled for 608 crankshaft revolutions.
Effect:
•Service Vehicle Soon Lamp ON

2.
P1191 -0
Fuel Rail Pressure Sensor Circuit High Input
•Common rail pressure is greater than 13500 kPa ( 135 bar )
•Above condition must be fulfilled for at least 1 s .
Effect:
•The system telltale is switched on.

3.
P1191
Fuel Rail Pressure Sensor Circuit Range/Performance
•Common rail pressure is greater than 14500 kPa ( 145 bar )
•Above condition must be fulfilled for at least 1 s .
Effect:
•Service Vehicle Soon Lamp ON

4.
P1191
Fuel Pressure System Malfunction
•Difference between actual and desired common rail pressure is greater than 150 MPa
•Above condition must be fulfilled for at least 3 s .
Effect:
•Service Vehicle Soon Lamp ON

and the TSB
Subject: Engine Z22YH, high-pressure pump, fuel pressure regulator - Defective (P1191 set)

Models: Engines: Option:
Signum 2003...2008,Vectra-C 2003...2008,Zafira-B 2005...2008 Z22YH,Z22YH,Z22YH None

Complaint: MIL on. P1191 set in ECU. 1. High pressure pump defective. vehicle not driveable. 2. Fuel pressure regulator defective, vehicle runs in emergency operating mode.
Cause: High pressure pump or fuel pressure regulator valve defective
Production: Improved fuel pressure regulators have been introduced in production as of engine number: Z22YH11768200 (15. September 2009).

Remedy:

General Remark:
Low pressure failure (P1191/5A or 52) are mainly caused by high
pressure pump defects, in some cases also by rail pressure sensor or
regulator.


High pressure failure (P1191/11 or 5B) are definitely not caused by a high pressure pump failure. It has been discovered that rail pressure valves are swelling and may stuck closed. Consequently the pressure inside the rail will increase and finally the engine stalls. If a new regulator is installed, ensure that only improved parts as of production date 226 09 (shown on down side of part, last 5 digits in 3rd. line) are used.

1. Check fuel feed pressure at high-pressure pump with
manometer (engine running)
Is primary feed pressure less than 3,4 bar?
Yes: Low pressure fuel feed failure -> check fuse, relay, intank
module.
No:
2. Measure fuel pressure in the high pressure rail at idle by
using Tech 2 Datalist.
Is fuel pressure in the high pressure rail less than 600 kPa?
Yes: High-pressure pump defect, replace.
No:
3. Pull off connector (two-core) of the fuel pressure regulator.
Measure the voltage of the fuel pressure sensor at 3000 RPM
(standing vehicle) with TECH 2.
Is Voltage greater than 1,2 V?
Yes: Fuel pressure regulator defect, replace.
No:
Defect is not clearly allocable to one component. Proceed
according to TIS 2000 service instruction.

I would start with checking supply and flow to the HP pump, a bad filter could cause this fault.

The pump is easy enough to check, A PWM Emulator*** on the RPR (Rail Pressure Regulator) First put a 5.5 ohm Resistor that can carry 4amps across the 2 pins (a 21 Watt Bulb may suffice) in the connector so you don't get an Open Circuit Fault Code. Have an Amp Clamp on the RPR, another channel on FRP. You can then drive it open and closed to force full pressure from the pump.
And at variable settings does the fuel pressure remain steady ?

The pressure sensor not so easy to test unless you have a gauge or pressure transducer that can measure up to 150 bar as independent verification.

A potentiometer in place of the FRP (Fuel Rail Pressure Sensor) can be used to challenge the ECU & RPR. Have an Amp Clamp on the RPR, another channel on FRP. As you adjust the potentiometer look for reaction to be smooth and quick on the Scope and PIDs - Injector Duration, O2S1 ..... (May help to keep the students awake :D :D :D :D )

***PWM Emulator - I use this: http://www.ebay.co.uk/itm/UK-10-50V-40A ... SwgmJXyOuq

(It is worth buying 2. Ideal for diesels that have dual point pressure control. IMV on the pump and RPR on the rail)


Technician
Yes, this is Common Rail - In Principle. And can be treated as such for Diagnostic purposes, to a point.

Bjorn, If you would like to have the Guided Fault Finding Flowcharts from OPEL for that Fault Code, all 4 Variants, PM me and I will be happy to send them to you.

Hope that Helps



EDIT
Andrew
I wrote this out and then got caught out by the "Captcha" All got deleted. Just now noticed that our posts crossed. Both with similar suggestions.

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Re: P1191 Opel Vectra Z22YH engine

Post by andrewbishop66 »

Thanks STC

Like the idea of using 2 pwm
have a diesel mondeo in on wednesday with a similar random intermittent fuel pressure problem think Ill order another pwm driver

Thanks andrew

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Re: P1191 Opel Vectra Z22YH engine

Post by STC »

Hi Andrew

I would not normally give so much away, but Bjorn is a teacher and it is for the greater good, our youngsters.

Hence I have offered him additional Guided Fault Finding by PM, it may become not sensible to duplicate too much on an open forum.
Last edited by STC on Wed Nov 16, 2016 5:18 pm, edited 1 time in total.

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Re: P1191 Opel Vectra Z22YH engine

Post by Tronic »

Hi STC!

Sorry for the delay STC and Andrew, but the forum will not alow my messages to show up instantly. I wrote yesterday evening but, as I now can see, they showed up here several hours later. Thanks so much STC for the write up and what really was invaluable information for me to continue on this GDI engine. My aim is to learn my students to pick the right component instead of just swap parts until it "seems" to work. I will be back and upload the Pico-files as promised. Maybe it is wise to upload a pic as well, thinking of them not using Picoscope. STC you got PM :)

All the best and thanks a lot STC and Andrew for the help!

Bjorn

PS I will order two of these PWM controllers

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