600.

that would make sense. Also, if I’m putting it in service mode with the rinda scanner, should it ever come “out” of service mode by itself? There was a few times I was trying to check, I’d hear a ton change, look back at the scanner and it read “normal mode.” I’m not sure if there’s a time limit where it goes back on its own or something’s bleeding through causing it

It doesnt show a malf 21 or 42 for the tps or est? When I said "already stuck in service mode", I actually mis spoke. Theres a table in your mefi that says rising reference edge 8.1 degrees, when there is no EST signal power to/from the distributor from ecm, the timing should read 8 degrees with a gun. So when you first start a mefi engine, if timings correct it starts at 8 degrees, when it reaches 300 rpms, it switches to the timing tables when est circuit to module in distributor is active . When you put it in service mode, it does something to the est circuit to module reverting to the 8 degrees and it turns up the IAC to stabilize the motor. IF the EST active wire to distributor had a bad connection as in Cass's 540 had on my dyno, the timing would be froze at the 8.1 degrees but IAC would NOT ramp up idle necessary so it wouldnt truly be in service mode, just wanted to clarify , Smitty
And once your scanner gets unplugged, or scrolled back, it would no longer be in service mode from anything the scanner did

I had a spare few minutes today and I ran down to the boat with the meter.
first, ecm is 16220371

I checked voltage on the bypass wire at idle, 4.0v. Rev’d to 1700 and it went down to 3.9.

key on, engine off, there was 400ohm resistance to the ecm ground(black/red) and the IC wire (white)

not sure if it not actually receiving 5v is the issue

No good if 5volt wires are 4.0v.

I was finally able to go down to the boat yesterday and got some more info on this. Key on, engine off: tps will read 0% for the first 1/3 of the throttle movement, then linearly increase up until the throttle stick is maxxed out and it reads 85% and and 4.3%.

Key on, engine running, the % and voltage increases as soon as the the throttle lever is moved like its supposed to and goes all the way to 100% and 4.55 volts

What would cause this? There's certainly resistance somewhere but any know where to start looking?

One other thing i noticed is on the Rinda scanner, it reads 13.8-14.2V and kind of moves around a lot between there while at steady throttle. On the dash, it reads as low as 13.1 and stays there. I need to verify the difference within the gauge today to make sure its working appropriately.

I started pulling inline fuses to all the accessories and I noticed that one fuse that powers the trim motor AND both tab motors.Is that normal?
Starboard tab moves much slower than the port.
When using starboard tab, voltage drops to 12.5 and recovers back to 14 quickly while still using it.
Port tab dumps to 11's and does not recover until you take your finger off the button.

It may be unrelated but Ill also look into that.

I don't see where you had the MEFI 1 inspected for internal damage. They are known to puke themselves causing all kinds of electrical gremlins.

As far as your trim tabs and drive trim mine are wired together as well. My tabs also drew down battery voltage the same (even at high rpm) and after ruling out a bad pump I hardwired the helm switch power in to the battery (w/fuse) and the issue went away. I've had to do this with other accessories as well and chalk it up to the 27 year old harness being corroded as forum members haven't suggest any other reasoning.

The MEFI 1 wasn’t tested. BUT

I just switched everything (intake manifold, carb, lines, etc) from my old boat to this one and it’s doing the exact same thing…. So it can’t be the ecu. Only thing left is a few battery/charging wires, ignition switch?

If you're running the Delco distributor, there should be nothing connected to the 4-pin connector. The distributor only needs power and the output to the coil (negative side).

Could be the video, but the engine doesn't sound right to me. Have you done compression and leakdown tests that were asked about earlier in the thread?

So since my last post, I did the carb, fuel lines, confirmed pressures, I put a new engine/charging harness, pulled the distributor and swapped it with my other boat and put a TB V module in…. With no f******* change. Today I mounted a go pro under the swim platform because it really did feel like it was hill/drive related..and correct me if I’m wrong but the water being thrown in the beginning of the video is completely not what is supposed to happen?


I will get the actual video uploaded soon. I’m just still out so this is all I have for now