4.3gxi false oil pressure alarm Driving me crazy

[Bob1971]

I have a 02 Regal 2860 with twin Volvo penta 4.3gxi's with duo props about 650 hrs each. Engine has neutra salt installed(however I have not used it- The marina flushes both engines after each lift) Starboard engine goes into a oil pressure alarm after a while on almost every trip. We can run up to 5-10 miles out without issue(anywhere from 3000-3600rpm) and then engine alarms into protection mode and drops below 2500rpm taking me off plane. If I go into neutral then alarm goes away and can relaunch and go back up on plane. Once it starts doing the alarm it will go off every few minutes and repeat the issue more often say 3-4 times in 5 miles. Replaced 3 oil pressure senders, replaced oil in engines and drives and filters, tried removing sensor from the circuit and it still alarms(temp and oil pressure gauges both always read in good range- connection to techs computer while running and the code goes from ok to fault a few times quickly and then into EPM. He believes it may be the wiring harness but I don't want a shiny new wiring harness or maybe the ECU which isn't cheap and then end up with the same issue like the other tried items. Any other ideas first? I guess I could have him swap ECU's with the port engine. Not so sure swapping a 10 year old wiring harness wouldn't get me two shiny wiring harnesses.

 

[Bob1971]

Re: 4.3gxi false oil pressure alarm Driving me crazy

Swapped the ECU's and still have the problem in the same engine. Did it once on about a 10 mile run going out Friday, 4 times on a 10 mile run Saturday coming back.Then Sunday not at all either direction...Any ideas Don S?

 

[Don S]

Re: 4.3gxi false oil pressure alarm Driving me crazy

How do you know it's an oil pressure alarm and not a temp alarm, or something else? Has it been hooked up to a diagnostic computer to find out what sends it into protection mode?

I would temporarily install a mechanical oil pressure gauge to the engine and go for a ride and see what the oil pressure is actually doing.

What is the letter/s after the 4.3GXi ?

 

[Bob1971]

Re: 4.3gxi false oil pressure alarm Driving me crazy

Has it been hooked up to a diagnostic computer to find out what sends it into protection mode? Yes. When hooked to diagnostic computer it trips to fault on his computer when it happens.

I would temporarily install a mechanical oil pressure gauge to the engine and go for a ride and see what the oil pressure is actually doing. Did that with him and the oil pressure reads fine.

I'll see if I can find the complete serial number in the morning.

 

[Bob1971]

Re: 4.3gxi false oil pressure alarm Driving me crazy

Regal says they are 4.3gxi-dp2 in there system but that probably doesnt help. So I searched the serial numbers are 4012059326 and 4012059328 and it shows they are 4.3gxi-b

As mentioned last night when connected to a diagnostic computer "low oil pressure" sends it into protection mode. This was the same when a oil pressure gauge was screwed into the engine but no drop of oil pressure on the gauge. The diagnostic went "fault/ok" a couple times before going into protection mode. It is intermittent as it doesn't always do it but it is often enough to be a headache. Had him disconenct the oil pressure sender temporarily and ground it out but still gives the same code with the sender out of the circuit and same condition.

Thanks,

 

[Don S]

Re: 4.3gxi false oil pressure alarm Driving me crazy

It's a 4.3GXi-B, that Regal number means nothing for what you are doing.

I would replace the oil pressure switch (tan/black wire going to it), since you have good readings on the mechanical gauge.

 

[Bob1971]

Re: 4.3gxi false oil pressure alarm Driving me crazy

Replaced it 3 times, been having this problem since last fall.

 

[Don S]

Re: 4.3gxi false oil pressure alarm Driving me crazy

Then somewhere in the harness the wire i going to ground which is what causes the alarm show, or the ECM itself has problems.

 

[Bob1971]

Re: 4.3gxi false oil pressure alarm Driving me crazy

We swapped ECM's between engines and still had same problem. So looks like the wiring harness is the next choice. Of coarse Volvo is pretty proud of them.