Unlocked D1 1996 ECU non adv evap

skewed

Member
Jul 26, 2021
8
0
st. louis missouri
i have a 98 D1 and i was told the idle issue (revs up in park and neutral) was due to a fault with the ECU.

are ECU’s swappable ? my friend has a spare but i’ve read that they are not interchangeable but i’ve also read another ECU will “learn” the correct values for your truck with a couple of drive cycles. i could also get one from Will that is flashed but don’t know if that will work??
 

ERover82

Well-known member
Nov 26, 2011
3,703
316
Darien Gap
i have a 98 D1 and i was told the idle issue (revs up in park and neutral) was due to a fault with the ECU.

are ECU’s swappable ? my friend has a spare but i’ve read that they are not interchangeable but i’ve also read another ECU will “learn” the correct values for your truck with a couple of drive cycles. i could also get one from Will that is flashed but don’t know if that will work??

Your 98 will need an advanced-evaps ECU, which this is not. ECUs are swappable but normally only when paired with the original security module. This one has had that requirement removed.

Your high idle will likely be cured with an adaptive reset.
 

p m

Administrator
Staff member
Apr 19, 2004
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La Jolla, CA
www.3rj.org
I was about to post something to that effect - but a non-advanced-evap ECU could probably be swapped into a later GEMS truck without adverse effects.
Swapping later ECU into an early GEMS vehicle will end up with a check engine light on, but I am not sure about the reverse.

Also, not as a general statement but my own experience - I could swap an ECU without any complaints from the security module.
 

robertf

Well-known member
Jan 22, 2006
4,524
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I was about to post something to that effect - but a non-advanced-evap ECU could probably be swapped into a later GEMS truck without adverse effects.
Swapping later ECU into an early GEMS vehicle will end up with a check engine light on, but I am not sure about the reverse.

Also, not as a general statement but my own experience - I could swap an ECU without any complaints from the security module.

there is something different about ael and non ael o2 sensors, but I dont know if the signal to the ecu would be compatible


your ecu likely had the f-out thing done to it so it doesnt care what is there as long as its something
 

skewed

Member
Jul 26, 2021
8
0
st. louis missouri
Issues were found with earlier pairings so the later ADV evap Ecus paired with the newer Alarm ECU did not require programming.
i tried an ECU from another ‘98 D1 but it did not work ? once installed i put the key in and all the lights came on but it wouldn’t turn over. do you have one Will that would work in my ‘98 D1 4.0 ?