Question for Don about a 175 EFI.

[headhigh]

My fishing partner’s 1996 175 EFI s/n 0G425296 mounted on 1996 Ranger 462V. Motor will occasionally (usually as you try to get on plane) act like it’s not running on all cylinders. Motor will only get up to 2500-2800 rpms and won’t plane out. When it clears up and finally jumps up on plane it runs perfect. It seems to be heat related as it happens most often when the motor is already hot. It has happened on the first run of the day, but not near as often as when it’s already hot. The only recent major maintenance was a lower unit replacement. New lower unit is an SEI replaced by insurance coverage. Problem arose roughly 3 months after the LU replacement. Engine operating temps and water pressure are the same as prior to lower unit replacement. Spark plugs have been replaced and compression check is good. It seems electrical because when it finally clears up it’s instantanious and not gradual. Where should we start our troubleshooting? Any parts we should replace right away? Thanks Don, or anyone else who’s seen this issue before.

[Zx175Bassman]

mine turned out to be ECU after a long hard process. Have it checked.

[EuropeanAM]

+1... though I would check spark and fuel pressure WHEN the problem is occurring.

[headhigh]

Well damn! Those are hard to find and $$$$$.

[JOE54]

Well damn! Those are hard to find and $$$$$.

naaa get it repaired

[headhigh]

naaa get it repaired

Where can you get that done?

[fishmaster]

My buddy went through a similar issue with his 200 efi. Seemed like it wasn’t running on all cylinders and always seemed worse when it was warm. Many trips to a dealer, many parts and many hours of himself searching he found the issue. It ends up there is a small fuel filter/screen inside the VST and it had debris in it. Ends up it would wash around in there and cause low fuel pressure. Found it by accident when they were checking fuel pressure and it was low when it happened. Cleaned it all out and this is his second year now without any issues. He also found it was hard on fuel when it was giving him problems like that too. Even when it was running good. Might be worth looking into.

[headhigh]

My buddy went through a similar issue with his 200 efi. Seemed like it wasn’t running on all cylinders and always seemed worse when it was warm. Many trips to a dealer, many parts and many hours of himself searching he found the issue. It ends up there is a small fuel filter/screen inside the VST and it had debris in it. Ends up it would wash around in there and cause low fuel pressure. Found it by accident when they were checking fuel pressure and it was low when it happened. Cleaned it all out and this is his second year now without any issues. He also found it was hard on fuel when it was giving him problems like that too. Even when it was running good. Might be worth looking into.

It's not really a "better" or "worse" condition. It is literally good or bad. When it decides it's going to work it goes from rough running, won't get on plane to "snap your neck" we're going right now!

[JOE54]

when its running bad take your hand and bump [smack] on front of ecu see if it comes to life = [inj driver bad] in ecu

[headhigh]

when its running bad take your hand and bump [smack] on front of ecu see if it comes to life = [inj driver bad] in ecu

Great idea! We’ll give it a try.

[bassnman81]

Check out this, he repairs ECU's

http://www.simonmotorsports.com/

[headhigh]

Check out this, he repairs ECU's

http://www.simonmotorsports.com/

Thanks.

[123trentm]

Check connection at ecu plug

[JOE54]

++++++ 1

[Macsimus]

mine turned out to be ECU after a long hard process. Have it checked.

x2 with emphasis on the long, hard process. Finally found a shop that was smart enough to water test with a different ECU. Bingo. I also had my original ECU repaired by Simon Motor Sports.

[headhigh]

x2 with emphasis on the long, hard process. Finally found a shop that was smart enough to water test with a different ECU. Bingo. I also had my original ECU repaired by Simon Motor Sports.

Wish we could find a spare ECU to test with. That would be great.