Have you checked the codes you're getting? If not then that's the first thing I'd do before even REMOTELY considering the ECU.

If you disconnect the battery for a minute or so, it will clear the ECU codes. Then if the check engine light comes back on, you need to check for them.

No offense intended but it seems to me you haven't methodically diagnosed things properly yet... I'm far from competent at that but then there are others on here that can help plus the Factory Service Manual provides a diagnostic proceedure you may want to check out first.

Off Roader
98 Montero with the Winter Package
89 Montero minty clean and reserved for overlanding trips or Cars and Coffee events
96SR (3.15:1 xcase, 35's) gone to the rust gods
96SR Build Up Thread
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