I'm thinking the same thing but I can't figure out what is causing it. I'm thinking something is causing the injectors to be fully open like dodgy wiring. I'm going to have to pull the blower off and inspect all the wiring around the back of the engine. I noticed last night that my 02 sensor wiring is badly twisted and I'm assuming it was when the extractors were installed. If it has a broken wire somewhere in there it could be a common earth for something causing max injectors flow..... But in writing that I'm sure I'd see 12v at the injectors so I probably just ruled that out lolimmortality wrote: ↑Sun Jan 07, 2024 10:42 am Sounds like a fuel system problem.
Where are you measuring your fuel pressure? What is your fuel pressure?
AFR keeps changing
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Spookydriftr
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Re: AFR keeps changing
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Spookydriftr
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Re: AFR keeps changing
It's being measured at the end of the fuel rail in the fuel pressure regulator
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immortality
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Re: AFR keeps changing
That seems fine, it's rising 1:1 with boost pressure in the manifold and that is what it should do.
Normally the base pressure is set at 3.5 bar (51psi) with stock injectors. Yours is a bit higher but if it was tuned with that then it shouldn't be a problem.
It is very odd though that the PCM is commanding 11.9:1 and you are seeing 10:1. When you are at WOT the tune goes into open loop mode and runs straight off the fuel tables (VE? Assuming Kalmaker is MAP based) in the tune with compensation for things like MAT and coolant.
I'm really not familiar with the changes Kalmaker has made for the VY tune to it's a bit of a guessing game from my end. What .bin .xdf and .adx are you using to log this?
Normally the base pressure is set at 3.5 bar (51psi) with stock injectors. Yours is a bit higher but if it was tuned with that then it shouldn't be a problem.
It is very odd though that the PCM is commanding 11.9:1 and you are seeing 10:1. When you are at WOT the tune goes into open loop mode and runs straight off the fuel tables (VE? Assuming Kalmaker is MAP based) in the tune with compensation for things like MAT and coolant.
I'm really not familiar with the changes Kalmaker has made for the VY tune to it's a bit of a guessing game from my end. What .bin .xdf and .adx are you using to log this?
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Spookydriftr
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Re: AFR keeps changing
this is a screenshot of the adx. ill sen a link to what i did to make it read boost... well what Kojab did lol
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Spookydriftr
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Spookydriftr
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Re: AFR keeps changing
What wideband are you running? Are you able to verify it's reading accurate?
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kojab
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Re: AFR keeps changing
You should have got back to me in 2022, was not sure how you got on. There is bound to be more than the Map sensor settings in your ADX which needs to be changed.
Kalmaker often makes changes which are not compatible with Holden bins and ADX settings making it very difficult and impossible to diagnose.
You mentioned you had extractors fitted recently. If they were new ones it's best to remove your O2 sensors before starting your engine and going for a good hard run around the block burning off all kinds of unwanted chemical fumes which often contaminate the sensors and become useless.