My computer was reprogramed to shut off cold mode at 105,mercruiser manual says stock cold start shuts off at 140. I had the same problem. Reprogrammed it works great.

BLOWNBOAT, who reprogrammed your ECU for you?

Pantera24-650HP, you are right on the timing jumper, but I didn't have my manual when we were timing so we set it for max timing with the light ( probably wrong). I always just do what you said on my boat and that works, but how do you know what the total timing really is on EFI?

blown formula, now that explains why their stupid manual says to use 32psi of fuel pressure. I know how to set the TPS, but I havn't looked at it since it was running ok prior to the procharger. Where do you install an EGT and wouldn't you need one on every cylinder to really tell anything.

It starts and idles great, but when you give it the throttle it sounds like it is loading up. Maybe fuel, maybe timing or a combination of both. Next time out, we might take a smaller prop to get it on plane and then maybe we can get it to warm up and then do some testing.

28 Eliminator,
I too am familiar with the chilly water syndrom.
Why don't you run a 120 thermostat with bypass and pressure relief?
I can program all of my enrichment out but I like the benefits of cold start enrichment; especially in our cold early season waters.

I'm not sure what the Merc ECU uses, but all of my enrichment is from 35* to 100* It sure helps those early morning starts in the Spring.
Dave

Dave, I know what your talking about. We were talking about the 120 thermostat, and I think we might get one. Where do you buy them at (whipple?).
That's probably enough to get it out the the enrichment mode.

Whipple or ASM
You'll need a bypass and pressure relief. If you have the PC crossover and thermo hsg, it's easy to modify rather than buying a new one.
Dave

You can get the 120* stat at West Marine in brass. Drill 3 holes per PC manual. Arizona Speed did the ECU. Get the MEFI-3 unit if you can. AZ SPD will exchange units. The MEFI 3 is much better and allows a lot more control.

Az speed and marine programmed mine also, it works great now.

sweeeeet, Thanks guys
Hey blown formula, the manual that came with this one doesn't say anything about a thermostat and 3 holes, but I don't beleive everything I read either. I know the MEFI 3 is much better, but it's quit a bit of coin to change. I know, it's a lot of money if you blow the motor also, but it seems like there are a lot of guys using the MEFI 1 with success. Just need to get the combination right.

Drill 1/8" holes (3) equadistant apart around the stat. This allows some water flow even with the stat closed. It works! Allows a little engine heat to be built.
As far as the MEFI 1, yes you can make it work but it is MUCH easier to get into dangerous territory with it. That makes the EGT gauge mandantory. If you are in a single engine, I would still use a dual display and put probes in both exhaust manifolds. Go above 1350* and the pistons are toast!! It give a real good idea of where/when to back off.

I believe you'll still need a bypass in order to keep the exhaust adequately cooled;)

As BF stated, an EGT gauge(s) is a worth while investment.