First Tow Home - Engine just died.

[freeflyernc]

So I have had a 2005 Launch 21v that we have put 900+ hours on and this weekend was the first time we were stranded on the lake. The boat started losing power (like someone pulled the emergency cut-off lanyard or turned the key off) at any speed. It was very random and we were on glassy smooth water. A little while later it did the same thing, but instead of a momentary loss of power it just shut down completely and wouldn't re-start.
I did some diagnostic work and found that there was no power to the fuel pump. I checked fuses (in the front and rear) and then I by-passed the neutral safety switch and oil pressure switch, again with no luck. The boat will turn over, but nothing else. I was thinking of going to buy a new lanyard safety switch as my next test since I can't jump it like I did with the others. Anyone have any other ideas? The boat was running perfectly until this happened.

[lively]

Do you have wiring diagram of where the fuel pump gets it's power input ?
What have you verified ?

Fuel ?
Spark ?
Compression ?

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[SquamInboards]

You verified that the pump has no power, did you try supplying it with power momentarily? Then you'd know if the pump was fried, or if there was a power supply issue. Also, before getting a whole new lanyard switch, take the old one out and physically connect the wires that go to it. That would tell you if it's the lanyard switch itself.

[freeflyernc]

I checked the lanyard switch and that is not the issue. I also just replaced the 3 relays near the computer- I know one is the fuel pump, one is the starter, and I don't know what the third is. This also made no difference. I have not tried to power the pump alone yet- that is my next step, but I don't get any power at the pump with the ignition on. I also found the quick connect for the pump and checked there for power, but I get nothing. The mechanic at the Supra dealer seemed to think it was a relay issue, but I have eliminated that. Any other thoughts before I tow this turd up to the dealer?

[lively]

So you have checked power from the output of the relay and you have power ? If you do then it's downstream to the pump . Do you have a wiring diagram ? If so post a pic


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[freeflyernc]

I don't have a diagram- I haven't been able to find one.

[freeflyernc]

Indmar was nice enough to send me a diagram. It is attached.14220

[lively]

I can't read it . Send to [email protected]


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[lively]

Verify power from pin 30 to relay and then if power is there . Verify power to pin 87 with ign on . Then report back


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[CJD]

Just to make sure...the pump power will only last for a couple seconds if the engine is not turning. So, if you are turning on the key, then moving to the engine to check the power, the power will already be off. It will take your first mate turning the key while you test the power at the pump to check it.

[freeflyernc]

Checking pins is a bit above my skill level. Not to mention it is a very tight space where the ECM is located. As soon as the river lets me I will be taking the boat out and to the dealer.

As CJD's post- The pump is loud when it works and used to run for 2-3 seconds when you turned the key. Now it is silence.

[lively]

All you need is a volt meter , 10 bucks local hardware store . Black lead to engine block red lead to pin 30 of the relay and as mentioned above the delay should be 3 sec that the pump is on to prime the fuel rails you need to see 12 volts DC "direct current" on the volt meter it will be the straight line one marked . All we are looking for is if the pump has it's power to turn on . Very simple to do once you have located the relay itself .

The ECM is not the location you want to check . The relay is . And that power is fed from fuse marked fuel comes out of the right side of fuse holder marked "b" the left side of that fuse marked "a" is fed from your ignition switch . You will save you some money and learn something . Don't give up .


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[freeflyernc]

So I remove the relay and test where it plugs into?

[lively]

Yes . Pin 30 is the relay pin and the PIN numbers are imprinted on the bottom of the relay to help see what pin goes where . If we have 12v at pin 30 then power is there for the relay , now you will need a paper clip or small pin to check pin 87 you need to check this with the relay plugged in half way and just probe the pin when you switch the ign switch on and off . All we are verifying is that the relay is sending power to the fuel pump . Then we will know that the operating system is working to start up . Once that's clear we will move to run circuit


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[freeflyernc]

I tried, but it was too hard in the dark. Dealer has it now. We will see...

[lively]

Awe .


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[freeflyernc]

Dealer just called- computer is dead. The fuel pump and fuel injectors won't fire without a bypass ground. He quoted me a price of $1500 just for the part- is there any place I can find one cheaper?

[lively]

I'd ask for a second opinion .


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[92SupraComp]

what sucks is that there are NOT Ford ECUs. They are special PCM ECUs. And the only one you can buy are used, for about $600... And PCM refuses to release their flash for what ever reason.

[awolfinwater]

Good luck with the troubleshooting. Hope it is not the computer. I had similar symptoms last Summer on a 2006 21v. The boat would just randomly die and not turn back on at times. Dealer found a problem with a loose ignition switch...no problems since.

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[jzelt]

I would agree with others based on other experiences. I had a snowmobile that acted up, took it to dealer, they diagnosed computer, manufacturer agreed, put in new ecu, and same issue, they went back thru and cleaned the terminals, connections, ground and fixed. (1200-1400 bucks to crappy 150 but still). If it would run with a ground bypass...I'm no auto or boat tech, but that would make me hope for your case that it is just a cleaning/tightening a wire first...

[freeflyernc]

So the MEFI was dead- if you jumped it I could get the fuel injectors and fuel pump to fire, but it wouldn't do it on its own. I replaced it (for $1500), got the boat home and it ran OK for about 20 min. Then it just started to die again.... Turned out that I also had a bad fuel pressure regulator (pressure was 85+ PSI). Replaced the regulator and fuel filter and I am finally back out on the lake. Hopefully this will be it for repairs this summer.

[freeflyernc]

Status Update:

Still have a slight miss. I replaced the spark plug wires and installed a permanent fuel pressure gauge. We drove it 3-4 hours this weekend and it “missed” less than 10 times. Seems to happen more at lower RPM, but happened at least once at wakeboard speed. Fuel pressure stays at 60-65 even when it misses.

What do you think I should do next? I’d love to get this solved, but now with the infrequency of the issue- I fear it will be impossible to diagnose.

[lively]

Man go by a Noid light and find out what is actually missing . Or when it's missing start pulling one wire off at a time till you find one that does not change . You need to verify what is what . If you have verified that there is pressure at the rails then go to spark . I don't know this engine that well . But tell me does this have a coil pack for each cly ?


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[freeflyernc]

No, there is a coil that hooks to the distributor cap. I replaced this about 2 years ago and the guy as skidim said these rarely go bad. My mechanic said to try the ignition module next. I was thinking about getting one of those fancy electronic ignition conversions for it. The price difference isn't too much, but I have no idea if this is worth it or how difficult the job is.

Mike

[lively]

Ok they are correct , reason I asked because COP (coil on plug) have rubber boots and will crack and cause the spark to ground to block through boot .

Don't throw money at something hoping to fix it . Lol I've spent thousands . Find out what is what and why it's caused it to fail . Less money spent happy wife ! So go get a Noid light and watch the spark miss or get weak . Or just pull one wire at a time till does not change the rpm of the engine . Then trace that back


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[Blackntan90]

Listen to lively, he knows what he is talking about... less money spent=happy wife!

[SquamInboards]

Listen to lively, he knows what he is talking about... less money spent=happy wife!

There's a great Homer Simpson quote about this, something like "If Marge isn't happy then I'm not happy. And if I'm not happy then Moe is VERY happy. But for once this isn't about MOE..."

And I agree with Lively on the diagnostic direction - it could be as simple as a bad plug wire... or if you can't trace it to a single wire, THEN you'd know it's higher up in the system. But don't throw any more expensive parts at it without more diagnostics!

[freeflyernc]

UPDATE: Coil and Ignition Module replaced- 5 hours without any issues. :) Only $155 Happy wife