ignition problem Opel Z20LET

[peter1002]

Hello
My engine runs normally when it is cold
when it is hot it is running on only three cylinders under 2,000 rpm
when I go over 2000rpm it is running normally

the ignition module and the spark plugs are new

Good day

[roquete]

Hi, i think you injector sequence is wrong, check Fuelling-Injectors phase

[astra vxr]

when its cold engine like a bit more fuel but its pig rich when its warm a z20 wil idle at 15 afr all day long but i tend to keep it a little richer but your log is al over the place and some places its well into the 10`s around 1000-1200 rpm hence why its going to run ruff it carnt burn that amount of fuel at such low rpm i wouldnt even put a car running 2 bar of boost under that sort of fueling lean it out under 2k and see if that helps it run a bit better aim for around 14 ish afr and see how you get on

[peter1002]

Hello
the engine is running so fat because he has been working on three cylinders

[Jadzwin]

The engine is not working on particulart cylinder or it is random ?

[peter1002]

It is always the fourth's. I have also tryed an other ignitionoutput on the ECU.

[Jadzwin]

Maybe to coil or injector are broken ?

[astra vxr]

coil or injector could also explain the afr as sometimes its ok and other times it looks ok

[astra vxr]

are you useing the standard z20 coil ?? if so that could be the problem as they arent very good at the best of times

[peter1002]

ignition module is new
Injector I have exchanged 3-4

[derOJ]

Hello
the engine is running so fat because he has been working on three cylinders

But an unburned Mixture of one cylinder will cause a lean afr

[peter1002]

Hello
have today Engine compression tested 12.9 bar all 4
cable from the ECU to kündmodul I also dipped
and also fat and lean gestelt
still the same problem

[astra vxr]

is it still on number 4 only ??

have you swaped injector plugs around and altered software to suit that will rule out injectors drivers on ecu

if the problem is still there after that the is either injector , plug or coil

[peter1002]

have it all changed still the 4 cylinder
Today I drove 20 min normal then it started again

[astra vxr]

how old are the plugs ?
its pig rich what ever the problem is
have you a differnt coil pack to try even though yours is new i would change it for another one and try it

i still think it might be a problem with coil pack getting hot and breaking down or dwell is wrong and its over heating



on a side note : best coil pack if you are running wasted spark is the ecotec one one we used them for years with 3 bar of boost and never had a problem with one

[peter1002]

the plugs is new
and how is it a setting that I that they stay cold

[astra vxr]

have you swaped injectors around ( swap 2 with 4 )

what coils do you have ( standard z20let one )

[peter1002]

Yes Bosch standart

[peter1002]

here I still have the connection diagram
and scope

[peter1002]

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