efi question
 

A buddy has a '02 502 mpi engine that just went "full rich" Runs so fat,fouls plugs instantly.Will the efi temp sensor cause this? Thanks BOB

Yes I would replace the water temp sensor.

Thanks,Tyler. BOB

The ECT sensor may be the cause, but you want to check for trouble codes before you start replacing things. You can check with just a paperclip and 12 volt LED. Also, just FYI, the last production year for the 502MPI was 2000.

Dave

Sounds like its in enrichment mode. Usually the temp sender.

Make sure the map sensor is plugged in or not damaged. This will show up at idle.

Thanks guys,checked the map.I have a spare efi sensor,easy enough to change.I go from there.
Dave,don't know? It's a powerQuest('01 not a '02 like I thought)definately is a 502 mpi ??? BOB

Merc made both the 502 Mag and 496 in 2001, they rolled one out while they closed down the 502.

Well,renewing the temp sensor didn't fix it? Got no codes and the fuel is fresh.Unpluged the map and the sensor and the scan tool picked up on that so it is working.Thanks for your help.I'll fill y'all in when I figure it out. BOB

Did you check the fuel pressure?? You may have a regulator problem.

Or leaking O-Rings or stuck injecter.

Now the 496 is going the way of the dinosaur..

Tyler,That's on tonights list!
800XCR,all 8 plugs are fat,the boat was run every month during the winter,don't think I've got 8 stuck injectors.Thanks,BOB

I had the same problem with my 98 502's. Checked fuel pressure with a gauge and it was extremely high. Changed out the regulator and everything was fine after that

bjablonski,fuel pressure was suppose to be checked tonight BUT this brunette called from Baton Rouge.My buddy is going to have to wait 'till tomorrow!! lol BOB

Any pics of the brunette?? :)

:rolleyes:


:drink:

Mr Gadgets,That's funny! No pics yet but it looks like it's going to be a good summer. BOB

Does she have a fuel pressure Gauge :D

Fuel pressure guage? Why would she need a ....Oh,right,my buddies boat.Completely forgot about it! lol She got my pressure "up"!! BOB

Now if you can just get your buddy's boat running.. LOL
Any luck with that??
You are allowed to follow up with pics of the Brunette!! :)

We're lookin at the fuel pressure tomorrow night.Pretty sure it's the regulator.The system is pretty simple.It's running at 6.8 gals per hour now,pretty fat!! You helped me set the backlash on my bravo XR last year,thanks again.The brunette... that will take some time.Second date is this weekend at the boat races in Miss.High hopes. BOB

OK,here's the deal.Water in the pressure regulator?! How's that possible you ask? When my friend washed his engine(some time ago) the vac hose was off the reg(at the manifold) and got water in it! Finally rusted and stopped working.And that's the rest of the story! BOB Tyler,where's those pics of that manifold? lol I'm going to "assume" I'll have to fatten this thing up with the improved air flow?