Engine Stall / Dash Air

[rvbiker45]

When you start the engine, do you engage the a/c before the lift pump stops running? If so, try waiting until that cycle is over, then engage the a/c. My aftermarket pump runs for a full minute, most seem to run for 30-45 seconds.
Also, inspect the wiring bundle going to the ECM. It should not have been disturbed during the a/c servicing, but who knows?

[mackwrench]

Originally Posted by pincherman

No. The engine definitely shuts down and quickly I might add. That's big part of the reason I'm beginning to settle on this being an electrical issue.

I can't believe the belt driven a/c compressor would shut this engine down at idle.....but

A sure way to see if it's belt load or electrical would to remove the drive belt and start engine. If it still shuts down, that would be 100% electrical issue.

[Wardjr]

I have the exact same problem on the same RV. I can confirm this is not a mechanical issue. This has to be electrical in nature. I can tell you what happens when you do this under way. It stalls or the check engine light comes on along with the alarm. I have observed that it seems to happen when the selector goes through the off position. So switching from AC to say MAX AC is fine. Switching from AC all the way over to vents or floor and it’ll stall. My AC works fine and the engine will stall turning it off also. This eliminates it being anything wrong with the compressor. I would love it if someone had an answer to this problem. I suspect this is a grounding issue and will continue to troubleshoot. If I find an answer, I’ll post it here.

[shootist]

Something like the ac clutch engagement is robbing juice from the ecm or crowding the ground. I would be cleaning grounds first then start looking at the ac clutch 12v wire. I just remembered there is a voltage spike absorber on these cummins. Like a capacitor rt near the ecm. When they go they can burn out the ecm. But they start causing little odd problems first. It's called a transient suppressor iirc.

[pincherman]

Thanks, Shootist.
I'm all for plug and play on this before I screw around with grounds. I'll pursue replacing the transient suppressor.
Anyone out there know where the ecm is located on my '05 Dutch Star (Cummins)? I'd have thought it was in the compartment next to the battery bank (pictured) but nothing in there looks like a big capacitor.

[shootist]

It's on the rt side of the engine block. Just under and in front of the injection pump.

[Ray,IN]

Check out this Cummins troubleshooting tree.
Shootist, the Cummins transient suppressor is a huge diode, used mainly on the 8.3L engine. When the engine is running the suppressor gets hot enough to burn your hand.
More here: https://www.agdieselsolutions.com/wp...90.V2.R3.1.pdf

[shootist]

Originally Posted by Ray,IN

Check out this Cummins troubleshooting tree.
Shootist, the Cummins transient suppressor is a huge diode, used mainly on the 8.3L engine. When the engine is running the suppressor gets hot enough to burn your hand.
More here: https://www.agdieselsolutions.com/wp...90.V2.R3.1.pdf

It's on the caps isl's as well. I would think it would be more along the lines of a capacitor than a diode. Acts like a condenser in a points distributor.
Just looked it up, they apparently do use silicone diodes to do the same thing. Glad you informed me.

[Ray,IN]

Originally Posted by shootist

It's on the caps isl's as well. I would think it would be more along the lines of a capacitor than a diode. Acts like a condenser in a points distributor.
Just looked it up, they apparently do use silicone diodes to do the same thing. Glad you informed me.

Yep, the ISL uses the same block as the ISC, the ISL is stroked, making the HP difference.

[Slow Life]

I know this thread is old but was the culprit to the engine shut down the "Transit Suppressor? Having a similar issue. TIA

[pincherman]

To answer your question as best as I can at this point, 'to a degree'.
I worked with another Dutch Star owner (same year & engine) and came up with the installation of a vacuum/mode switch that's used in the main dash panel for controlling A/C, heat, vent etc.

https://www.comfortairgr.com/product...pcon-rv218476/

I installed the new part and it stopped the engine cutout when turning the switch past the off mode at the 12 o'clock position to heat/defrost.
The caveat to all this is that I believe my freon has again leaked out and my compressor is not engaging so until I get that rectified I will not know for absolute sure that I've solved this. I do believe the engine 'cutout', orange check engine light, was happening without the compressor being engaged and the switch being moved but, as I said earlier until I get the freon leak fixed and the system charged I'll feel even better about fix.

[pincherman]

BTW- To be clear my 'to a degree' comment was NOT addressing the Transit supressor. I never really looked into that possibility.

[Wardjr]

For me, a rebuild of the selector switch absolutely resolved the issue. I would have preferred to replace it like Dave did. But, in an effort to be timely with my trouble shooting. I chose to disassemble the switch itself. It is a multi layer, laminated design and two of the plates would short in certain positions. It’s been working great since the repair. I’ll replace it if my repair fails. I was waiting on Dave to verify with his before giving a response. Hope this helps

Bob

[Slow Life]

Thanks I will start to look for what is causing the spike or short. Frustrating because it doesn't cause a code to showup.