We drove our '98 U295 (Cummins C8.3 325hp) two days ago down to a resort 60 miles away from home. No issues. We started driving back home this morning and 10 miles down the road started having power issues. We could not accelerate from the red light. 10mph max got us into a big grocery store parking lot and we sit here now trying to diagnose the problem. We had a problem with similar symptoms 9 months ago, which centered around the King Controls system. Before we get into that I want to start with this first question. Sitting still in the parking lot, brake on and transmission in neutral, it idles at 6,250 rpm. Pushing the accelerator all the way to the floor I only get 1,400 rpm's. Should we get more than that?
Maybe. Depends on how the throttle request is handled by your ECU . I would think that over 2000 should happen but I dont know how your ECU works or it's inputs.
Assume you means idles at 625 RPM (which is a little low)!
If you suspect a throttle issue, just open the back and manually throttle up-- pretty easy to verify.
And, if the throttle is working as it should, remove the primary fuel filter and drain it into a glass jar to see if there are contamination issues. Replace with new filters (primary and secondary).
Update: I didn't pull the wiring connectors to the King Controls apart, which is where the problem was 9 months ago, but I did just squeeze them all real hard and that seems to maybe have resolved the situation, at least temporarily. Think we're going to get back on the road and see what happens.
Check to see if King throttle control is opening to full throttle. check with one person depressing throttle pedal and other visually watching cable to fuel injection pump.
Or sometimes fuel shut off solenoid is not opening all the way.
Should also be 2 return springs on the throttle area,a common failure as they wear out where they hook on.
idle should be around 800.
check fuel shut off solenoid
1)Cable tie fuel shutoff solenoid in full up position. 2)Make sure brake lights are not stuck open or all bulbs burned out.
Just a guess, but fuel filter??
Jim
2002 U320
OP Update: Only made it another mile down the road before it happened again. I went and jiggled/squeezed the wire connectors again and the problem went away, so I know it's there. Before starting out this time I pulled apart all four of the connectors (14 wires in all going into the King Controls box), cleaned them as best I could on the side of the road with Q-tips, and reconnected. Made it the 40 miles home with no issues. Not sure of the best way to ensure this doesn't happen again.
Are the connections coated well with dielectric?
Sometimes the connections are worn out so they need to be replaced or you could throw
the connector away and connect them permanently. Sometime contact cleaner will fix it.
If it were me, I'd consider cutting them all and putting an inline connector there. Maybe something like: Amazon.com: WMYCONGCONG 5 Kits 16 Pin Way Waterproof Electrical Connector... (http://www.amazon.com/WGCD-Waterproof-Electrical-Connector-Automotive/dp/B071KDSFS4/ref=asc_df_B071KDSFS4/?tag=hyprod-20&linkCode=df0&hvadid=312540934012&hvpos=&hvnetw=g&hvrand=10654357831358628466&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9030766&hvtargid=pla-569502772926&psc=1)
Yes I did contact cleaner and then dielectric the first time I had this problem.
That would do it, wouldn't it. Replace 4 separate connectors with just one.
Common knowledge and be a dangerous thing.
di·e·lec·tric
/ˌdīəˈlektrik/
adjective: dielectric
having the property of transmitting electric force without conduction; insulating.
noun
noun: dielectric; plural noun: dielectrics
a medium or substance that transmits electric force without conduction; an insulator.
Smearing stuff on connectors to prevent corrosion is an undertaking not to be taken lightly.
Clean the connectors with the appropriate Caig product and be certain that all are making good electrical contact.
Home | CAIG (https://caig.com/)
This is the can that doesn't leak after first use:
CAIG D5S-6-LMH DeoxIT Spray 5 oz. Original Can (https://www.parts-express.com/CAIG-D5S-6-LMH-DeoxIT-Spray-5-oz.-Original-Can-349-230?gclid=CjwKCAjw682TBhATEiwA9crl3zHL262QFi2raP9D-GB7xsm62hTlc2Xp5zZulYH3q9_skdUDVeTCBxoCqqYQAvD_BwE)
There used to be a similar product years ago called blue stuff,no longer made.
If you have prior it will return, when, probably when it the biggest pain. The pins and sockets have worn or are not being held together with internal resistance. Regardless of what you change to make sure all wiring is environmentally protected in some manner. Have you tried physically holding connectors tight with a external tyrap?
Scott
You can watch the Caig DeOxit dissolve corrosion. It looks as though the corrosion is melting away.
What doesn't make sense is cleaning the pins and sockets of a connector them smearing an insulating grease over the connectors.
I'll try the wire tie idea to hold connections tighter, though none of them were found loosened beyond the snap that holds them together.
Also going to search the forum for how folks have replaced the King Controls with something else.
1998 295 should be a mechanical injection engine with no ecm. My coach has been converted to an air throttle that is very reliable. The conversion kit is available on the web. Parts are still being made.
If that comes to pass don't throw the King away,starting to collect old parts,maybe can piece one together.
I clean the sockets and spray atf on everything.!
Automatic transmission fluid
Think I would go with the Deoxit over spraying oil on it and atf is oil.
When I was driving over the road the pig tail would sometimes make intermittent connections. Used WD-40 on the connector didn't have issues after that. Common trucker fix.
Roland
I've used ATF on many areas. Never had a corrosion or poor connection issue with it. As mentioned, it gets sprayed into my trailer connectors and the inlets of my air tools continually
I'm sure that some product may be mo better on paper but it works for me. Low tech when low tech works.
An interesting opinion on dielectric grease.
Dielectric Grease vs Conductive Grease (https://www.w8ji.com/dielectric_grease_vs_conductive_grease.htm)
To quote for the learned article:
"The important physical characteristic is that any grease must have low enough viscosity to push out of the way at contact points, be water or liquid resistant, and be stable enough to remain in place as a protectant against moisture and air for a long time. It will not do any good to apply a grease that does not do required functions of excluding air and moisture, and lubricating the interface to prevent galling or fretting, for extended periods of time."
"Contrary to Internet rumors, advertisements, and articles low viscosity silicone dielectric grease will NOT insulate pressure connections. Silicone dielectric grease will prolong connection life as well as, and have just as good conduction performance, as a properly selected metallic powder grease (conductive grease). On the other hand, and improperly selected "conductive" grease can actually cause connection problems."
The female portion of the multi-pin connectors lose tension over time. That is the problem. Ford Motor Company, in the 1960s used conductive grease liberally on the multi-pin connectors carrying power here and there in its relay driven masterpieces of the day. The arcing between the male and female parts of the connector caused hard carbon to form creating resistance in the connection.
On my journey to this age, I finally decided that clean and dry works for me, so I apply readily available plumber's silicone grease to the non-conductive parts of multi-pin connectors to try and keep moisture and dirt on the outside where it belongs and trust on the lubricant left behind by Caig Product's DeOxit to keep the metal parts from corroding. Or I solder and shrink wrap everything in sight.
WD-40 Water Dispersant number 40 for those who were wondering!
Chris
Consider NO-OX-ID "A Special" Conductive Terminal Grease (https://baymarinesupply.com/no-ox-id-a-special-conductive-terminal-grease.html)
This has no metal flakes or particulates in it. I use it as a thin film on studs, lugs, washers, and nuts on most bigger 12v connections. Torque to spec. Works great, one little tub will last a lifetime for most.
For multi-wire connectors, it the objective is to keep out water, a dielectric grease seems to work well.
Glad you made it home safely after that, well done.
Would love to hear an update on your ultimate solution to this problem, I have the same model (but not yet the same problem)
so any info is good info.