Volvo engine harness

[KenVC]

5.0 GI PWTR
I am getting desperate. My mechanic has tried continuity checks, reflashed the mefi 3 etc. and we cannot get this engine to start. It tries but spins quicker then backfires and tries to run backwards. Bob at OBD feels the problem is in the engine harness and I am willing to buy a new harness but the harness is obsolete. No one has it. I need harness number 3860525. Does anyone know where I can find one or know of someone that can rebuild mine?

 

[Don S]

Re: Volvo engine harness

Chances are slim that you will find one, why not just find where the problem is in the harness.
Do you have bright blue spark out of the coil when cranking the engine? It sounds more like weak spark or lack of fuel. Which one.
I assume all the fuel pressure checks have been gone through and all the tests in the OEM service manuals have been checked.

Is there a lot of rust or corrosion on your engine? Wiring harnesses seldom fail completely unless the engine was under water.

 

[Maclin]

Re: Volvo engine harness

What is your history with this boat? Did this just start happening? Is this a replacement engine? or has any other major engine work been performed on it recently? "En"quiring minds and all that....

 

[Tail_Gunner]

Re: Volvo engine harness

You need to check your timing events. Are you using a scan tool...If your knock sensors arnt readable the mefi would advance the timing...How's the timing chain :twitch:.. You can alway's pull the Harness plug and check resistance of each circut a short or gounded wire..It would show up quick.

 

[KenVC]

Re: Volvo engine harness

I've finally given up and ordered a brand new 5.7 mpi. Thanks everyone for your help.

 

[Don S]

Re: Volvo engine harness

Man, that's just a tad extreme.

 

[KenVC]

Re: Volvo engine harness

Yes it is Don but I am very cautious when I go 30-40 mles out tuna fishing. I don't want any problems. There were other issues also but the main problem (obviously) was not being able to start it.
Don, I'm curious, I grew up in Lynden,WA. Where are you?

 

[FloridaBarrs]

Re: Volvo engine harness

Chances are slim that you will find one, why not just find where the problem is in the harness.
Do you have bright blue spark out of the coil when cranking the engine? It sounds more like weak spark or lack of fuel. Which one.
I assume all the fuel pressure checks have been gone through and all the tests in the OEM service manuals have been checked.

Is there a lot of rust or corrosion on your engine? Wiring harnesses seldom fail completely unless the engine was under water.

Just an FYI on this thread. I have a 1998 5.7GS and had harness problems that cause it to not start when cold. I found that when I wiggled the harness plug while someone was turning the key it would start once it was warm it always started again. A short time later while trying to clean the contacts and expanding pins to ensure tight contact, I had a couple of pins pop out and then it was clear this was a result of corrosion. The boat has never been under water.

I just traced every wire and pin with a multimeter then used crimp-on quick connects for each wire and all is well now.