Z22SE For one year now I can't still make my car run smoothly

#1
Hello everyone! First of all I want to apologize for my English because I'm Lithuanian myself and some "technical" terms may not be correct in this post.

The car in question that I'm having problems with is my Opel/Vauxhall/Holden Astra G (2001) with 2.2L 16V 147hp (108kW) petrol engine "Z22SE". I've had this bucket for more than a year now and since day one it has not run correctly.
I've had a bad timing chain, bad pump chain and loads of other stuff that's been broken when I bought it or broke while I was driving it.

At this time I have ONE main problem (or lots of little problems). My IDLE is very rough (a video will be at the end of this post) and fuel consumption is not normal compared to other Astras with this engine. Also if you push on the gas harder while it's idling - it almost stalls-out and then revs up. Usually when driving and giving the engine load it stutters and tries to stall out but then gets the Revs back up and drives normally.

What I've already done to my car:
  • New timing chain set
  • Water pump chain set
  • New MAF (Mass air flow) sensor
  • Blanked off EGR Valve and EGR Cheater connected
  • New Lambda (O2) sensor (the 1st one). 2nd one is removed because no catalytic converter
  • New Throttle body
  • Tried spraying flammable fluid around the engine bay to find vacuum leaks - Didn't find any.
  • The coil packs where already changed when I bought the car (but to used ones, not new)
  • Changed the spark plugs while changing the Timing chain
Today I acquired an OP-COM OBD2 scanner and recorded Live Data, but this part stood out for me:
I was driving until 60 seconds, then from 60 to 210 seconds I was idling (which was very rough) and then from 210 to 282 I took off
Video that I mentioned: Youtube: Z22SE Rough Idle
(edit for testing)
I really doubt that anyone will try to read that but if anyone will...

The "Simplified data" file screencaps (to see what you'd be downloading):



What do you guys think about the Intake Manifold ? This idea popped up in my head recently about the rubber gaskets where it meets the head, but at the moment I cannot change those or remove the manifold to check

I am very thankful to anyone who will read this or will try to help me, because I've lost hope...
Cheers mates!
 
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#3
might be a few things;
a bent or damaged valve
a bad coilpack
a faulty throttle body
a bad coolant temperature sensor
Valves were checked when replacing Timing Chain, so I'm led to believe that those are fine.
Is there any way to check the coilpack? Or just getting a 100% working one and plugging it in?
Throttle body came to my mind as well because it sometimes revs up to 2k rpm and stays there for 10-15seconds, might look into that one
Which coolant sensor ? If it is showing coolant temperature correctly even in diagnostics could it still be bad?
Would the Data file be of any help ? (The recorded data which the screenshots are taken of)
 
#4
Have you checked the fuel pressure? A faulty fuel pump could cause stall on load (I experienced it on another car). Do you also notice it when the car is stationary or only when it is moving?
 
#5
Modified-GM-Opel-Vauxhall-Z22SE-inlet.jpg


I think you could be drawing some air here. When you did the egr delete did you remove the pipe that goes to the inlet manifold or is it still there.
If you have not already then you should remove the pipe from egr valve to the inlet manifold and fit a blanking plug on the manifold
 
#6
Your livedata is quite short but it is obvious that the engine is overfuelled. The long term fuel trims are extremely low.
LTFT_table_181218.png

FT_2d_181218.png

Check the injectors along with the fuel pressure. A longer livedata would also be useful. ;)
 
#7
Have you checked the fuel pressure? A faulty fuel pump could cause stall on load (I experienced it on another car). Do you also notice it when the car is stationary or only when it is moving?
It idles very roughly and tries to stall out (but doesn't) when the gas pedal is left alone. When I'm driving around it sometimes loses power or just stops gaining speed

Your livedata is quite short but it is obvious that the engine is overfuelled. The long term fuel trims are extremely low.
Check the injectors along with the fuel pressure. A longer livedata would also be useful. ;)
I may be able to record longer data tomorow if that would be any help.
Could a vacuum leak (air getting in from somewhere it shouldnt like others mentioned before) cause engine overfuel?

Also, just a thought, if it is "OVERfueling" I guess fuel pressure is good ? :D

edit: Why is there no "MAF" reading in op-com and recorded live data ? If I find a way to read out what MAF is showing - what should I be expecting to see to determine if that part is working how it should ?
 
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#8
Could a vacuum leak (air getting in from somewhere it shouldnt like others mentioned before) cause engine overfuel?
No, it would cause underfuel. However I had similar thoughts as IDI AMIN for the rough idle first. How did you blank that hole?
Also, just a thought, if it is "OVERfueling" I guess fuel pressure is good ? :D
Maybe, but I'm not convinced that there's only one root cause for these symptoms.
edit: Why is there no "MAF" reading in op-com and recorded live data ? If I find a way to read out what MAF is showing - what should I be expecting to see to determine if that part is working how it should ?
There's no MAF in Z22Se engines, but MAP and IAT. Both are logged in livedata.

You not mentioned, but I suppose there aren't any error codes?!
 
#9
There's no MAF in Z22Se engines, but MAP and IAT. Both are logged in livedata.
You not mentioned, but I suppose there aren't any error codes?!
Oh s**t, I always thought that sensor before throttle body is MAF.. I should rethink everything now while diagnosing from now on..
Does bad IAT can cause something simillar ?

Also. No error codes except secondary oxygen sensor, because there is none (cat delete, straight pipe)

No, it would cause underfuel. However I had similar thoughts as IDI AMIN for the rough idle first. How did you blank that hole?
It's not blanked off, the hose is still there

EDIT:
I just remembered, could a faulty throttle body cause similar things? Because couple of times it looked like it was stuck and engine wouldn't go lower than 2k rpms, and 60% of the time while driving after letting of the gas pedal - the RPMS would stay higher and then drop off (but i'm pretty sure that air coming in after the throttle could cause similar stuff..)
 
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#12
The IAT recorded 7-9 °C. I think it is normal if the outside temperature was similar.
it was around -3 to +3 °C outside, so I'm sure it's working correctly

You should remove it and blank the hole. The end of the hose restricts the air flow too much. But it is independent from this problem.
What you're saying is - that wont solve my problem but it would be better for my engine in the long run?

also I'm going to record some live data in couple of minutes. I'll PM you that like the previous time. Thank you for your patience :)
 
#16
View attachment 68681

What happend before the mark? I see many similar sections. The green fields seem normal, then the throttle pedal had been released. Did you really release it?
Mainly after idle pressing the pedal will stutter the engine, jerk the car and then it will be good. But also when you release the gas pedal after some driving it would sound like those cars with launch control and sometimes it pops fire from the exgaust (i guess overfueling)

I will post couple of videos tomorow of the bad idling and the other things that are going on
 
#18
Ok. Now you only have to find out what causes the overfuelling. :)
You can get closer to the source of the problem by checking the spark plugs. This is a good guide to read the sparks correctly: https://mechanics.stackexchange.com...of-lean-or-rich-carb-settings-on-a-motorcycle
But be cautious with the reinstall of the plugs:
https://z22se.co.uk/threads/cracked-head-2-2-vx220.5803/
Thank you again for looking into everything, I appreciate it a lot, because none of the shops in Lithuania have tried to find the solution.
The spark plugs were bought brand new when changing the timing chain and replaced

I might try to get my tools back from "a friend" and take some pictures of my spark plugs
 
#20
You want to remove the egr pipe and fit one of these

1545243779093.png


As someone already said , you can get it from your local volkswagen dealer
or from ebay here

https://www.ebay.co.uk/itm/Thermost...9:g:OiYAAOSw0odbsa~s:rk:1:pf:1&frcectupt=true

or you fill it with coins and chemical metal.

https://z22se.co.uk/resources/permenant-block-for-egr-hole-on-manifold.32/

https://z22se.co.uk/threads/egr-pipe-removal.27034/

I would get this done first and see how things develop afterwards


It also sounds like the lifters/tappets are a little noisy
 
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