VP 8.1gxi MEFI 4 Engine Data
 

8.1 GXi-D S/N 3869264 1996 Cobalt 250

Background: I chased an issue with a cam shaft position sensor (bought cheap one, spacer, no spacer) for a whole season until I fixed it and was so happy I litterally screamed. Boat ran 58mph and felt like Rocky at the top of the stairs.... Had a kid and the boat stayed
was laid up for 21 months.

Took it out two weeks ago and it was a turd, would only do about 3200 rpm but the motor sounded fine so I blamed old gas. So the wife and I just maintained cruise speed up to my parents and back (30 miles) and some other cruising and burned 3/4 of a tank.

Put in $180 worth of premium and invited some friends out today (I was so confident that was the problem). Fires great, sounds fine, steady idle with no surge. Exit the no wake and I can't even get on a plane with 6 people and a full tank of gas. Sounded just aweful too, not like a miss, or a knock, just like ill. Hook up my techmate pro and no codes, no limp mode, no check engine light, no alarm, 100% octane..

I did notice one thing, I swear after I fixed the camshaft sensor I was getting 20+ degrees of spark advance at 1500-2000 Rpm. I'm currently seeing 7-8.

Does anyone have the FSM or an engine data table so I can have a something to compare to for trouble shooting? Or can anyone confirm the spark advance by RPM (ball park).

I hate to start chasing this issue, but it feels too familiar and no idea why I would rear its head again.

I remember your cam sensor issue 3 years ago to be exact. You bought from rock Auto was the first mistake - Volvo did things differently with it but now its looks to be all NLA for the early Volvo 496 s as well - just like it is with Mercruisers.

Do you have the OEM service manuals for the engine & diagnostics to get all your needed info ?

I have them all for sale. Including the early 496 cam sensors brand new still being made like I posted in your thread 3 years ago..

carter cool fuel that volvo uses sheds internal paint and gets up in the injectors. You can have your injectors check out by whomever that does that kind of professional service including myself. 9 years experience and currently 3 different machines.

I just mailed mine away this morning to be rebuilt. For the cost I think it's worth trying even if it turns out to not be the problem

if it's from paint and other crap getting in them, you have to get the crap and paint out of other parts of the fuel system too.

Any suggestions on how to do this? Fuel pump assembly is only two seasons old, so remove that from the equation it's just braded line to the fuel rail. So basically the fuel rail is all that's left? Or I can just buy a new fuel rail off eBay (probably knock off but who cares it's just a tube).

Maybe just pull the fuel rail the rest of the way off and use brake clean and a pipe cleaner ?

I got them all out and looked into them with a light and didn't see anything visible on the inlet side, outlet side had some black build up but the at the nozzles.

Also, the guy that I sent them too after getting my year/make/model emailed me back and said he sees these style injectors clogged with ethonol all the time. So hopefully that's the case with mine.

It all comes down to maintenance. Actually lack of proper maintenance for the complete fuel system by far is more of the issue than e 10. I am glad you got all your past issues worked out 3 years ago inwhich finally got your engine running as it should. Like I said back then you can not go out and buy what ever cam sensor plus volvo set up needed to be 100 percent correct. Glad replying got it done resolving your issues.

Could your fuel injector service provide the proof that your injectors where clogged and what was the material that clogged the injectors. Ask him what M/S he is testing the injectors per RPMs ? Ask him how you should properly lay up your marine engine plus your fuel system to help protect your fuel injectors for years to come.

Ill ask about the RPM, but he said you put a drop of 3/1 oil into each one before you lay it up. But that to me sounds like asking for trouble with seals pulling the rail every year.

thats some funny stuff right there. he really does not know much on the marine side if that was his reply for properly laying up a marine application. Like I said, its all about proper maintenance and proper lay up especially for the fuel system.

So he never mentioned that once you pull the injectors off the fuel rail that it is very wise to install new o rings plus how to reinstall ?