yes I see what your saying! Great observation thank you! That’s good I can just replace that if we need to.

hey that’s great to know. During troubleshooting did the bad ECM throw any error codes? I guess if that’s not working correctly anything is suspect.

I have not tried that. Someone also suggested taking the engine cover off too if it’s a thermal issue. It’s worth a shot. Thanks

Actually you have the same exact ECM chip (861720T2) that I have! I found an old post that you made when you were having the issue where you posted that number and the issue was similar. At 4000 rpm it was fine. I don’t have the gas smell issue but it’s definitely very similar in that it’s cutting Rpms.

I did call Mercury unfortunately they don’t have the part (they stopped making MEFI around same time you had issue) but they did point me to a third party that rebuilds ecms.

I think we might be on to something here I appreciate your info.

I had exactly the same problem on a 1999 7.4 in a baja. After searching fuel pressure, tps, etc... it turned out that my exhaust manifolds and risers were clogged with rust. My fault for not changing them every couple years. Installed new manifolds and risers and it ran perfect. Next time it looses power,shoot a heat gun on the risers and if it’s anything like mine they will be extremely hot. Also when it looses power, let it idle for a while to allow the manifolds to cool then then throttle up and see how it runs. Again, if it’s like mine it will run fine until the manifolds heat up. Good luck

Did yours not occur at higher RPMs like 4000 do you know? That’s what makes me think it’s more of a sensor/computer issue as if it were getting hot at 3100 it most surely would get hot at 4000.

Frustrating that you both had same issue but different causes. I think I’m going to have them check those other things before replacing ECU though.