2000 Merc 5.0 V8 EFI No Start

[Squab]

So here is my problem, I have a 2000 merc 5.0 V8 with EFI. It powers a Bravo one. I have had the boat going on 5 seasons now and it is always reliable. I can just turn the key and it fires right up. Last weekend I was out on the bay last week and it just died. So here is the back story:
Went to fuel up and noticed it was a little low on oil, noticed some in the bilge, so I added about a half a quart. All was fine, we cruised at about 3200 RPM for about 30 minutes and it just cut out. I tried to fix on water but to no avail. When We got home, I pulled the Air cleaner to inspect and saw some soot on the intake and the pulleys. (figure it was running too rich). When I turn the key, the engine turns but will not start. I hear a 3-5 second whine when I turn the key and assume it is the fuel pump. As I turn the key, there is no fuel shooting down from the injectors into the throttle body. (This is odd). I looked for lose wires and noticed nothing. The next day, I went to the boat, turned the key and it started right up, came to temp and ran fine. (Problem solved)
The following day, I go up turn the key, fires right up. I put in neutral throttle to 2000 rpm and it dies. When I try to turn over, I get same result as the first time, no Fuel to the throttle body. I checked the oil pressure level when turning key and there is pressure. The tank is 3/4 full. I am lost. Can anyone advise me or point in correct direction?

 

[Bondo]

Ayuh,.... No fuel,..?? Inspect the contents of the fuel filter for anything but clean fresh gasoline,.....

With a 'puter controlled motor, ya can't get very deep, without a 'puter to read what's goin' on, or not goin' on,....

 

[muc]

do have the Thunderbolt ignition or do you have your serial number?

 

[alldodge]

Sure could use the serial number
As the motor is cranking, do you see the Tach showing at least 300 rpm?

 

[Squab]

Gonna run up there now and get serial number. I do not think Tach shows anything when it is cranking. Bondo, I began taking off the fuel connection at the back of the throttle body and a bit of fuel came out. I did not have a second wrench to use on the second nut so I just left alone. Bondo what can I do?

 

[Squab]

Bondo, I used to have a 4.3 with a regular carb and I remember the fuel filter being at the carb inlet. Is that where the filter is for the EFI? I could also pull the fuel water seperator and inspect if there is fuel there but that is before the fuel pump.

 

[Squab]

Update time: Went up to cover before rain. Turned key, Starts up. Ran for 2 minutes at idol and then quit. Let it sit while I covered (5 minutes) turn key, sputtered like it wanted to start, then nothing.
Not sure what ignition system it has, does not say thunderbolt anywhere like my old one did.
serial numbers 0L380350. Any Help will be appreciated. Puzzled

 

[muc]

looks like you have Thunderbolt ignition.
might want to go to the sticky's and find the troubleshooting steps for the thunderbolt, confirm that the sensor in distributor is indeed bad and replace it.

 

[Squab]

Do you know where the fuel filter is on this EFI model. I know where the Water separator is but I am thinking there may be one by the Throttle body

 

[Fun Times]

Serial numbers 0L380350.

= MERCRUISER MEFI 3 BRAVO 5.0L EFI (GEN+) model number 4M32027M1. Here's your parts catalog through iboats, http://www.iboats.com/5-0L-EFI-GM-305-V-8-1999-2001-0L331631-THRU-0M299999/dm/view_id.1683216

The fuel filter should be located down to the lower left corner as you face the engine from inside the boat...It will look like an oil filter. If you haven't done regular service interval maintenance over the years, it's time and you'll want to start with the fuel filter. Here is a general view of the filter and it looks like you may have the black cool fuel cover surrounding the filter itself. The top and bottom half's will pull apart and there should be a clip (or two) that is holding them on/together. http://www.iboats.com/Fuel-Filter/dm/cart_id.812495366--session_id.656478810--view_id.1683245

There isn't a filter at the line like your old carb had. You may have to prepare to check fuel pressure which takes a special fitting to the inlet fuel line at the throttle body where it sounds like you started to remove the fuel line.

 

[Squab]

Correct me if I am wrong, but is that the Fuel water Separator?

 

[Fun Times]

Correct me if I am wrong, but is that the Fuel water Separator?

Yes it is and pretty much does both.... Some models might also have an inline filter before that filter too...Just depends.

 

[alldodge]

I put in neutral throttle to 2000 rpm and it dies

Cranking in throttle only mode and giving it more throttle and it still will not fire?

 

[Squab]

So I changed the fuel water separator, took off fuel line, could blow into gas tank, removed fitting at the back of the throttl, turned key watched soda bottle full with fuel when priming, now what,

 

[muc]

The fuel injectors need a signal from the ECM to fire. Tha ECM needs a signal from the ignition system to fire the injectors. Check to see if you have spark when the engine won't run. If you don't, see post #8 above.

 

[Squab]

OK, can I just take the ignition coil wire off the distributor and hold over ground? I have to turn key and I am jsut one man. Too far to see. Is there an easier way? I think no, but just checking

 

[Squab]

Second question, Can I go to Auto zone and get a code tester for a GM and put it to see if there are codes?

 

[alldodge]

OK, can I just take the ignition coil wire off the distributor and hold over ground? I have to turn key and I am jsut one man. Too far to see. Is there an easier way? I think no, but just checking

Sure if you can see it, would be easier to go and pick up a spark gap gauge at the auto store.

Second question, Can I go to Auto zone and get a code tester for a GM and put it to see if there are codes?

No, the ones for auto's will not work.

You can make one with a resistor led and a paper clip. Find the DLC connector, install led as shown, then the paper clip. Turn the ignition ON and start counting the flashes and pauses. Exp 12 is flash, pause, flash, flash and longer pause



And here is the TB-4 and 5 troubleshooting guide

 

[Squab]

Ok, where is the DLC located? I see the hook up to what I would think is the Computer, but is it the connection toward the bow or stern, if I am looking at the engine from the stern side.

 

[alldodge]

The location can vary but in most all cases its next to the ECM (computer). It should have a cap over the top which is removed to expose the contacts