Hi all. Engine is a 1996 200hp EFI, serial number 0G361511.
Symptom: While accelerating and as speeds approach the upper 40s / 50s, the boat intermittently loses power for a split second and resumes. At first I thought it seemed to coincide with hitting bumps on the water. Now I think I might be wrong about that. It seems to happen only at higher speeds, and far more often/consistent if I trim up. Sometimes it does coincide with bumps, but other times not. The loss of power is a split second. It feels like i'm hitting a rev limiter OR as if a wire has a shaky/lose connection.
Relevant data
1. This engine was recently transferred from one boat (a 1996 Charger 295TF) to another (1993 Nitro 2000DC). The symptom was present on the charger and has continued on the Nitro.
2. The symptom is present with any prop I've tried: I have 23, 24,and 25 pitch Tempest Plus props. the issue is identical regardless. Hole shot is outstanding with all props.
3. The symptom is present with any amount of fuel in the tank.
4. I noticed voltage is under 12v when running (11-ish) and tach stopped working. Friend-of-friend boat mechanic said that's a sign of a bad voltage regulator so I have that ordered and will change it.
5. In an attempt to debug this (and get more performance) changed the ECU from stock to a Brucato and the symptom persisted. Now that I know my stock ECU was not the issue, I will sell it. But at least I know it's not the ECU.
6. When the motor was transferred to the other boat, compression was checked, injectors serviced, fuel pump and impeller replaced.
Questions
1. Could a failed voltage regulator create such a symptom?
2. I know there is a rev limiter in the ECU (brucato adjusted mine), but is there another form of rev limiting that I could be hitting? Could timing or setting on any of the various throttle/idle/etc. set screws affect this?
I will have an entire day on Friday to install the new voltage regulator and try other solutions.
Thanks in advance for any help.