Marvel Mystery oil in a 2004 5.0 engine

[Dp59]

Did you change all fuel filters? Not sure if you have cool fuel module in addition to water separator. Cool Fuel takes 2 filters.

Only 1 fuel filter on this model

 

[Scott Danforth]

First new fuel filter/water separator, no help. Compression test 180 on all cylinders. Check fuel, no water in it. New dist. cap and wires. New plugs
New fuel pressure reg. as old one was maxed out at 36 lbs. no codes show when reading with Tech Mate software. Flushed injectors with K100 with fresh fuel from can. Thought i would try some of this before we go new ecm route.

Any compression reading higher than 150 is either a bad gauge or oil in the cylinders

You may want to check your fuel pressure against spec

Its not your ECM or coil

 

[Dp59]

Any compression reading higher than 150 is either a bad gauge or oil in the cylinders

You may want to check your fuel pressure against spec

Its not your ECM or coil

My boat machinic of 35 years did the compression test and said 150 to 190 is normal for the 305

 

[lprizman]

Dies under load is starving for fuel

 

[paulswagelock]

Have you run on an external tank to eliminate Tank issues?
crank sensor going bad?

 

[Scott06]

When it sputters and dies - take the coil wire off the distributor , ground it , and see if you get spark. Also the crab style MPI distributor caps are known throuble spots have you replaced yours.
Have you measured the fuel pressure especially when it dies?

 

[Dp59]

Have you run on an external tank to eliminate Tank issues?
crank sensor going bad?

Tried that as thats what we think it's doing .ran new fuel from a pail after disconnecting fuel line and put hose on it to engine. No difference?

 

[RaceCarRich]

What did you use for a pump during your test?

If was me, I’d get $24 Harbor Freight fuel pressure gauge, attach to fuel rail and go for ride. Even better if you have a buddy to keep an eye on it.

 

[Dp59]

What did you use for a pump during your test?

If was me, I’d get $24 Harbor Freight fuel pressure gauge, attach to fuel rail and go for ride. Even better if you have a buddy to keep an eye on it.

We did that along time ago. Thats why we put new pressure reg on and fuel pump

 

[RaceCarRich]

Ah. I saw you tested and changed the reg but didn’t know you changed actual pump and tested afterwards. I’m assuming the after numbers were good. You’re definitely throwing a few bucks at this.

 

[Dp59]

Thought i would post the results.
replaced the ecm and everything runs perfect now.
Sent the old ecm in to OBD Diagnostics and they called back saying they had never had one act like this one.
At random times the ecm would stop sending instructions to the fuel injectors so it would stall out when testing.
Nice to get out on the water again.