1996 5.0 efi

[fourwinns1996]

My 5.0 EFI is acting rather strangely. Starts up fine runs well for a short period. Then once temp comes up to around 150 or so she starts sputtering and stalls. Can restart but then she stalls again in say 2 seconds. Each subsequent attempt at starting it becomes more difficult to start. Today I put it back on the trailer drove it home, about 10 minutes from the ramp, and it started right up like nothing was wrong. In previous years it has had a similar problem when it would stutter 1 time during the day them pick up and run fine the rest of the day. Although it was hard starting once it was warmed up and shut off it ran fine once stared. Are these problems related? New fuel injectors 3 years ago. Fuel delivery? Temp sensors? Needle valve on the fuel reservoir? Yes I had issues with this also! Sorry for the ramble but trying to give as much info as possible about the boats history!

 

[alldodge]

Serial number please and I'm guessing its a TKS carb?

 

[fourwinns1996]

Model engine is 50FAPNCS. Serial number T01296531 but it is fuel injection. No carb!

 

[alldodge]

Yep don't know why I said TKS last night, must have been tired

Its a Ford 302 so a OMC / VP

Have you checked the fuel filter contents for contamination?
Is fuel pressure between 31 and 39 psi?

 

[Horigan]

I’m wondering if your ECU is going into over temp limp mode due to a bad engine temp sensor or connection. I believe there are separate sensors for the gauge and ECU. Along with alldodge’s suggestions above, you may want to confirm the engine temp sensor for the ECU is putting out the right values.

 

[fourwinns1996]

I am acquiring a new filter. Will check for contents when I make the switch. I have no equipment to check the psi. Are you referring to after the low pressure pump or the high pressure pump? I was thinking temp sensors as well. Temp increased to 150 pretty rapidly by my estimation. Thermostat? I have owned the boat since it rolled off the assembly line and I do not recall ever changing any of the components being discussed. Thank you for the help. Any thoughts are helpful at this point. Is there a way to clean any contamination out of the tank should I find some in the filter?

 

[alldodge]

HP pressure

 

[fourwinns1996]

So fuel filter has been changed. Very small particulates in the fuel from filter. Removed water pump and impeller appears to be in bad shape. Have new impeller. I will get that installed and let you know the result.

 

[fourwinns1996]

So new impeller is installed. Turned the key on and off several times to make sure new fuel filter was full of fuel. Started it up and ran for about 5 seconds then stalled. Got it started 1 more time but only for say 1 second. The impeller was obviously a problem but not the cause of my stalling issue. So All Dodge it is time to look at the more expensive items. Fuel system here we come.

 

[alldodge]

Sure does, going to need some pressure readings

 

[fourwinns1996]

My friend with the gauges to measure pressures was unable to help me this week so today I got ambitious and fiddled with it some. First I removed the new fuel filter to see if it had fuel in it which it did. So reinstalled that and disconnected the upper fuel line from the low pressure pump. Turned the key to the on position several time but no fuel was coming out of the pump. So I started checking everything attached to the pump. Turns out the electric plug to the pump is very loose. After making sure the connection was as secure as it could be. I turned the key to the on position as again. After several turns of the key fuel started coming out of the top of the pump. I reconnected the fuel line turned the key several more times then started the motor. Is the loose connection causing the pump to run intermittently? I feel kind of stupid for not checking this earlier but I have never disconnected the pump. Do they do this during winterization or is it just plastic deteriorating over time? I will keep you posted of any new developments! My tow vehicle is in for service so I can’t even take it to the lake to see how long she will run. 2020 has been bad all around!

 

[alldodge]

Is the loose connection causing the pump to run intermittently?

Yes Sir, that will do it

 

[fourwinns1996]

Had the boat out yesterday! Running like a champ. Temp never went above 150 and engine never skipped a beat with the wire secured! Sorry for the trouble over a loose wire.

 

[alldodge]

Thanks for the follow up, happy boating