tl866 programing a vs stock memcal

[VL400]

Try 12V, they are old style EPROMs so tend to be higher voltage types. They are not the old old 21 or 25 volt style though.

Can ID the type and then check the data sheet to confirm it.

[trexbreah]

vpp 12.5
vdd write 6.25v
vcc verify 5v
puls delay 100us
i assume there the correct voltages
but every time i write the chip it last for about 8hours and starts to degrade my trip home today blew black smoke like a diesel and used about 20ltrs to go 3km but on the way to work the same chip felt awesome compared to that i think i should unplug the computer from the car instead of just the earth strap on the battery before installing the memcal

i don't understand it though it goes well but then degrades
im using the1 enhanced v6 bin

[Dylan]

Got a data log? Possibly another external problem like wiring or sensor causing dome erratic fuelling and when you burn a new chip it clears all learnt trims and DTC's.

[Dylan]

Maybe even next time take a read of the chip first and compare to the original one and see how the data is.

[antus]

Are you writing stock physical chips or from other source? Could just be bad chips. Also if there was soldering can be slightly melted memcals that dont make good connection.

[trexbreah]

the chip reads and verifies but after its been in the ecu for a while say 2hours i will notice that some of the spark timing or fuel perameters will come up as 00000. or ffffff after a day 98 percent is corrupt and the car gose into limp mode
i thought it might be sunlight becouse i had the computer acces panel off so i turned the computer around but that didnt help i also put a sticker on the chip but nada

i also found another chip it dose the same thing

i blank it for 45minutes any less shows up errors when i blank check
i open the bin file and program it auto verifies i wait a few hours with the chip unplugged from power i verify it again after, it verifies successfully
disconnect battery in car negative lead remove old chip plug in new chip re secure ecu connect battery starts fine drives fine wait a few hours repeat the procedure to remove chip and it wont verify read chip and save file and it hase the errors i exsplained

[Dylan]

Send one to me if you want to try. My GQ4X has never failed me. If I had an ecotec chip here I'd do one and send it but I dont have any late model memcals.

[trexbreah]

i made up an adapter i just plug in the chip no soldering necessary
two of the chips are from recked vts the rest are vs memcals the computers where from running cars although wrecked
a nrmal holden tune dose it as well

[trexbreah]

hopfully i sorted the problem im writing at vpp voltage 13.5 if the error happens again i am going to chang the ecu it might be that if it persists i might send you the chip or a few
but at the moment i wiped the chips

i dont think its the tl866 after the chip is writen to i would assume its pretty hard to erase without a UV light and i assume it would take a few days in sunlight to form read errors

[trexbreah]

noobish question but what do i do to advance timing would i add or subtract from the values in the table
im sort of confused about that