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André
07-13-2007, 04:25 PM
My turn to need help...

Having some troubles when hitting the throttle hard.The engine almost die then take off.
I have checked the fuel pump screen and replace the fuel filter,clean flame arrestor so far but would like to check fuel pressure.Where do you hook up the gauge?
After the pump is the fuel filter then the TBI unit and only plain tubings in between them.
Do you remove one tubing and install an in-line gauge with fittings that screws into the fuel filter and the TBI unit?
Is there a in tank screen that can be block?
T.I.A.

rspiecha
07-13-2007, 05:07 PM
How do your plugs look??? Do you still have the water fuel separator on the boat. In front of the engine, on passenger side of engine, mounted to fiberglass.

Rob

rspiecha
07-13-2007, 05:08 PM
Does your engine smell rich at idle???? run rought at idle???

André
07-13-2007, 11:50 PM
Plugs are goods and no rich mixture smell but i found some condensation or liquid in the MAP sensor.Removed it and dried it with a hair dryer.
Couldn't lake test it with hard rain coming...We'll see tomorrow!
No fuel separator on my boat.

JimN
07-14-2007, 12:31 AM
André- with the ECM mounted next to the motor and the MAP sensor below the throttle body, the hose, and sometimes the sensor, can collect fluid. The symptom is exactly what you described. I'm not sure the hair dryer got it all but unless it was set on a really high temperature, it probably didn't hurt anything, either. If you still have problems next time, find a way to check the sensor for a leak- you don't want to use an extreme amount of suction on it but it should seal well. If it's leaking, it'll need to be replaced.

There should be a screen in the end of the fuel pickup tube but I think you already found the cause of the problem.

André
07-14-2007, 08:53 AM
André- with the ECM mounted next to the motor and the MAP sensor below the throttle body, the hose, and sometimes the sensor, can collect fluid. The symptom is exactly what you described. I'm not sure the hair dryer got it all but unless it was set on a really high temperature, it probably didn't hurt anything, either. If you still have problems next time, find a way to check the sensor for a leak- you don't want to use an extreme amount of suction on it but it should seal well. If it's leaking, it'll need to be replaced.

There should be a screen in the end of the fuel pickup tube but I think you already found the cause of the problem.
Thanks Jim!
I did remove the fuel tank and clean everthing around the pick up screen wich was maybe 10% blocked .I change the map sensor hose for a longer one and made a loop lower then the sensor so that any liquid won't enter it.
Going skiing with partner's 197 this morning,will try my boat after that...

JimN
07-14-2007, 11:06 AM
See if the MAP sensor harness will allow you to reposition it above or at the same height as the fitting on the throttle body, with the hose facing down. The loop will keep the fluid out of the sensor but it would still be possible for the symptom to reappear.

If you still have problems, check the anti-siphon valve for debris, too.

André
07-14-2007, 12:24 PM
See if the MAP sensor harness will allow you to reposition it above or at the same height as the fitting on the throttle body, with the hose facing down. The loop will keep the fluid out of the sensor but it would still be possible for the symptom to reappear.

If you still have problems, check the anti-siphon valve for debris, too.
Harness is too short to allow to position it upside down.
But the good news is that the boat is running fine now!!!:)
After hitting it hard 10 times in a row,neibghbors were looking at me funny,holeshot was back to the "Amazing" level again!!!
Thanks again Jim!

"Bring Dr N next patient please...":D

bret
07-14-2007, 12:24 PM
Andre, a guy in a ski club was having the same problem and it turns out to be his perfect pass. Somehow, with it on, hit the throttle and boat just stumbles, makes like a "whooping sound" from under the engine cover. (94 boat too, 1564 hrs)

Turn it off, disconnect the power to it, the boat is flawless. Something in the Perfect Pass start up is causing this. He was told to temporarily put in a toggle switch to cycle power to it. You do this AFTER you have the boat running, and turn it off BEFORE you turn the boat off, both work fine. He has some new part coming in for his, not sure what it is, I had to fly out that afternoon. Just something to look at if you have PP and it's been on when this happened. May also be totally irrevelant. good luck

edit - post at the same time - guess PP is not your problem :D

André
07-14-2007, 12:28 PM
If you still have problems, check the anti-siphon valve for debris, too.
I was thinking about that yesterday while i had the gas tank out but i thought it was a check valve.
Never found it.thought that it might be inside the 90 elbow right on the gas tank connection where the hose goes so i dismantle the manual shut off and the elbow but didn't find anything in there...
What does it look like and where is it supposed to be?

André
07-14-2007, 12:32 PM
:) Andre, a guy in a ski club was having the same problem and it turns out to be his perfect pass. Somehow, with it on, hit the throttle and boat just stumbles, makes like a "whooping sound" from under the engine cover. (94 boat too, 1564 hrs)

Turn it off, disconnect the power to it, the boat is flawless. Something in the Perfect Pass start up is causing this. He was told to temporarily put in a toggle switch to cycle power to it. You do this AFTER you have the boat running, and turn it off BEFORE you turn the boat off, both work fine. He has some new part coming in for his, not sure what it is, I had to fly out that afternoon. Just something to look at if you have PP and it's been on when this happened. May also be totally irrevelant. good luck

edit - post at the same time - guess PP is not your problem :D

Doesn't seem to be but i didn't have a skier in tow.
Thanks anyway for taking the time to post your version of another possible problem that could help somebody else.
Love my 94 wake...

JimN
07-14-2007, 07:20 PM
The anti-siphon is in the barb where the fuel line attaches to the right angle fitting. It's just a spring-loaded ball bearing but as long as it keeps gas from siphoning out, it works. Problem is, with the pump drawing gas from the tank at the rear of the boat, the valve can actually cause other issues.

Glad to see that it's running right again.

"neighbors were looking at me funny"

If they don't look at you funny, you're not trying hard enough.