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apexi pfc start/idle problem

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ok so mapped my buddys sti(98 sti v5) tonight, cars bone stock bar a dump valve and full exhaust , all went well until I turned the car off and tried to start once warm , the car fires up no problem but then hunts and wont rev this only happens around 50% of the time , I took a few data logs and it only looks to hunt when battery v is unstable I tried adjusting dead times but it did not really help , tried making the map richer and leaner but still no joy , my thoughts are it could be a problem with the dump valve but im unsure , also some times when it starts the rpm will go to 1200 then come down to 800 as set but some times it just gos to 800 .

thanks for any help im abit confused on it

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The first job after installing a Power FC is to perform an idle learn procedure. Failing to do this will often result in poor idle quality and the sort of problems you mention. There is a nice write up on the procedure here:

If you are using the FC Datalogit software you can save and copy your maps as initialising the PFC will wipe all your tune data.

thanks for ur advice , I tried this today twice and still having problems , checked for air leaks , blocked off dump valve to rule it out , still the same , plug in the stock ecu and all is fine , Im beginning to think its a fault with the ecu , maf voltage looks to be ok from what I can see online but I might try changing it just to rule it out , its very odd as some times it starts fine then others when it fires the revs die and it hunts up and down some times even cuts out .

ive added a few logs of the problem ,the tpsv changes abit when starting is that normal ?

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