Need Help on 5.8fsi Couple of Issues

[Briha1978]

Hey guys, I have been a lurker for some time and since reading through many posts I can’t find exactly what my boat is doing. I’ll try to be as clear as I can.
My boat. 1996 Chris Craft Concept 230 w/5.8 FSi. Sticker plate says OMC COBRA Volvo penta 58FCPNCA

ended up pulling manifolds and risers to get at the spark plugs. These issues below were before the manifolds and risers.

Issue #1 boat will run in idle but only if you have the throttle down a quarter. If you bring it to neutral it will eventually sputter and die. I’m also having a surging issue. It will start. Go up and down and then if in neutral without throttle it usually dies. IAC valve or ?

Issue #2 boat will plane and will run good and then studded until I bring the throttle down. After it clears up if I try to push it it will do the same.

I have read there is a SLOW mode on this boat where the ECM looks for readings from two sensors. The boats ran well up until last year when it started studdering at about 2500rpm. Changed out the fuel filter but still did the same thing.

Things that have been done to it.
Volvo OEM exhaust gaskets and riser gaskets
spark plugs
distributor cap/rotor
new batteries
fuel filter

if anyone can give me insight on what to do I would be very appreciative. Thanks Y’all.

 

[alldodge]

Howdy
I would start with
Fuel pressure at the rail should be 31-39 psi

 

[Briha1978]

Ok I’ll let you know. Are you talking at idle or cruising?

 

[alldodge]

Ok I’ll let you know. Are you talking at idle or cruising?

Both, Pressure should be within range from idle to WOT

 

[Briha1978]

AllDodge. Love the name. I have a Plymouth duster 71 340 4speed. Anyways. I don’t know if it’s my gauge but it says I have zero fuel pressure at the front rail and at the rear as well. Also what is the firing order abs where us number 1 on the distributor. I work on Mopars usually.

 

[jesse_boston]

You mentioned it starts to stutter around 2500... on these EFIs it has an oil pressure and water temp sensor for the SLOW / limp mode like you said. They are separate sensors than the dash gauges for oil and water. One of those sensors might have gone bad (or you might be overtemp or have low oil pressure).
The sensors are on/off type, there is a single wire that runs back to the EEC that will be grounded if the sensor trips, which triggers the slow mode. In slow mode, it will cut off the injectors above 2500 or so. I thought that it should stabilize out when you go back to idle though, your issue sounds a little different.
It might be enough to just unplug the wire from the two sensors when it is happening to see if that's the cause and to see which one is failing.
I don't know where the sensors are on the motor though...

Related, if you don't mind my threadjacking for a minute, have you been able to get service and parts okay on your engine/outdrive? I've heard parts are hard to find and expensive because they only made them (the 5.0/5.8 fsi) for 2 years and then dropped Ford entirely.

 

[alldodge]

Did like those 340's

Need to get the pressure up, with pressure that low your probably running lean and it can burn a piston

Firing order

 

[Briha1978]

AllDodge. Primed fuel pumps. I hear the rear and the front one. Now I get only 14-15 but it starts to drop fast. I have pulled the fuel tank compartment and I am trying to the the fuel pick up tube out. I have to soak it in some pb and have a go at it tomorrow. What else should I be looking for?

 

[alldodge]

Have you checked the antisipon valve (barbed fitting on top the tank)?

Before removing the tank tube, use a piece of thin wire or string trimmer cord and push down in it. If it goes far enough then the tube is not clogged

If you have a hand vacuum pump, connect to tank and see how much vacuum it takes to pull fuel

If vacuum is low then the pump(s) may be the issue if there is not another restriction

 

[Briha1978]

AllDodge
Checked screen on pick-up tube. Clean. So that one more thing to check off the list. I have a low pressure fuel pump on order and it’s supposed to be here Saturday.

 

[alldodge]

Just throw that thing away and don't replace. They cause more trouble then there worth, the fuel filter will catch everything needed

 

[Briha1978]

Throw the screen away? It’s on the pickup tube?

 

[alldodge]

Throw the screen away? It’s on the pickup tube?

Yes, they cause way more problems then they help. The motor has a 10 micron filter so it will catch anything that comes out of the tank

 

[Briha1978]

Changed out both fuel pumps. Hi and low. Only getting 18psi at the rail? Any ideas. I am thinking i have a block age in the rail? Or?

 

[alldodge]

Changed out both fuel pumps. Hi and low. Only getting 18psi at the rail? Any ideas. I am thinking i have a block age in the rail? Or?

No, if there was a blockage you would see close to 100 psi. The regulator is what controls the max pressure

Dumb question, is the high pressure pump running, and did you bleed the air from the rail?

 

[Briha1978]

How to bleed air from the rail? When I turn the key I do hear them both prime. I’m pretty sure. After pumps were changed. It did start but then died after about 3 seconds.

 

[alldodge]

The schrader valve, where you measure pressure

 

[Briha1978]

Ok I’ll try that. I’ll let you know. Thanks.

 

[Briha1978]

I have had this issue for years. Changed both fuel pumps hi pressure and low pressure. Spark plugs, wires, cap and rotor, fuel pressure regulator, and coil. The boat starts runs for 3 seconds and dies. Screen in the tube in the tank. Checked out to be ok. AllDodge was helping last year. Also 2 new batteries. Impeller as well. I seriously can’t figure out the reason it is running and then stopping. Please help.

I posted a new thread but he told me to revive my old thread. I apologize. So where do I go from here? I have the boat in my driveway and it is accessible unlike before when it was in a storage area. What is interesting is after I changed out both fuel pumps the boat would only run for 3 seconds and die.

 

[dubs283]

I'd check for voltage loss at one or both fuel pumps. If okay then move onto ignition