Community Forums

jrheick · 07-11-2018, 05:23 PM

Hello! I don’t know if this would be more appropriate being posted in the Monaco owners section, or here. I chose this forum as I’ll be updating here the diagnosis with the fix. So, here’s the problem. My 2012 Knight 40PDQ with 34K miles has the check engine triangle lit with alarm. Fortunately this happened on the final leg of our 6K trip. This coach has the Maxxforce 10 350 HP and the ECM has the latest updates. The diagnostic code I could pull shows SPN 3664 FMI 5. The tech will need to investigate the fuel delivery to cylinder 6 and that will require the removal of the valve cover to check and trace the wiring. Does anyone here know if that valve cover for this engine is removable through the bedroom & closet?

Gdawgs · 07-12-2018, 04:14 AM

Quote:

Originally Posted by jrheick

Hello! I don’t know if this would be more appropriate being posted in the Monaco owners section, or here. I chose this forum as I’ll be updating here the diagnosis with the fix. So, here’s the problem. My 2012 Knight 40PDQ with 34K miles has the check engine triangle lit with alarm. Fortunately this happened on the final leg of our 6K trip. This coach has the Maxxforce 10 350 HP and the ECM has the latest updates. The diagnostic code I could pull shows SPN 3664 FMI 5. The tech will need to investigate the fuel delivery to cylinder 6 and that will require the removal of the valve cover to check and trace the wiring. Does anyone here know if that valve cover for this engine is removable through the bedroom & closet?

Yes it is. That's how the tech will have access. Good time to replace the primary fuel filter.

Dennis_K · 07-12-2018, 10:43 AM

Quote:

Originally Posted by Gdawgs

Yes it is. That's how the tech will have access. Good time to replace the primary fuel filter.

And the secondary filter on the side of the engine...

jrheick · 07-12-2018, 01:30 PM

Thank you Gdawgs and Dennis_K. Both those filters were replaced during the last two year end maintenance sessions performed on this coach. The tech must have had access from underneath, or maybe through the coach battery tray. Either way is possible on this MH.

I dismantled the closet this morning to have access to that 2nd engine cover. The MH is now in the hands of Regional International here in Buffalo. And I'll follow up here when I have an update.

Traps90 · 07-20-2018, 07:12 AM

Quote:

Originally Posted by jrheick

Hello! I don’t know if this would be more appropriate being posted in the Monaco owners section, or here. I chose this forum as I’ll be updating here the diagnosis with the fix. So, here’s the problem. My 2012 Knight 40PDQ with 34K miles has the check engine triangle lit with alarm. Fortunately this happened on the final leg of our 6K trip. This coach has the Maxxforce 10 350 HP and the ECM has the latest updates. The diagnostic code I could pull shows SPN 3664 FMI 5. The tech will need to investigate the fuel delivery to cylinder 6 and that will require the removal of the valve cover to check and trace the wiring. Does anyone here know if that valve cover for this engine is removable through the bedroom & closet?

Any word on what your problem is with the check engine light

jrheick · 07-20-2018, 10:09 AM

Quote:

Originally Posted by Traps90

Any word on what your problem is with the check engine light

Yes indeed. Spoke with the shop foreman this morning. Number 6 fuel injector is bad/leaking, and he wants to replace the injector wiring harness too. He told me the harness is hardened, cracking, and has a rub mark on it. I gave him the go ahead. The coach should be ready Monday.

I'm just befuddled that an injector would go bad at 34,000 miles.