Love my Bus but...

[Blacksheep]

I don't need a good one! I already have a Gibson F5 that everyone that plays it says to never get rid of it! I know its a good one. It just needs a good player!

Ace

[blue_goose]

Ace
All it takes to make the ecm work is the power harness must have Pins E, B, and D grounded .  Pins A and C must have 12 or 24 volts depending on your ecm.

The vehicle harness must have ground on pin A1 and ignition plus on pin B3.  If the ecm is good and you have fuel and air the engine will run.

Where this happened after you changed filters, I'll bet you don't have any fuel getting to the injectors.

You need to make sure that when you turn the switch on that the stop and check engine light come on and then go off.

Hope some of this helps

Jack

[Blacksheep]

Jack what your telling me about all those pins makes very little sense although I do know where they are. I'm definitely not that good with  electronics and maybe that's another reason I should look for a different coach to own over this multi-wire, sensor sensitive, POC I own!

Jack, thinking about this solenoid that was changed to allow it to shift correctly, would you know what exactly it is and where it might be?

As for the CEL and the SEL? Yes I turn the key on and they both light up for about 5-8 seconds and they both go out. That is when I start to crank the bus. After hooking up the pro-link, I have NO codes, and no historic codes. All the other parameters that could be changed have to be done by someone OTHER than myself!

I haven't looked at it yet today. The day has gone so well so far and I didn't want to ruin the mood! 

Ace

[zubzub]

Knowing how to run an engine in some kind of by pass mode is mandatory for piece of mind.  I heartily suggest you follow Jack's suggestion re the grounding of pins etc (providing you know that he knows what he's talking about).  Knowing that in a no start due to sensors etc you can by pass all and get down the road will make you feel good.  BTW I agree with you on electronics, it's why I have a '53 4104 and a '68 Volvo 220.  On the other hand I converted my Volvo's points system to electronic ignition, best thing I ever did to that car, hums at 100 MPH, pulls better through the whole range and starts on a dime.  The cool thing is I keep the old points dizzy etc in the back with the spare wheel, only weighs a couple of pounds and I know I'm always getting home. Giver.

[Lin]

Ace,

I know nothing about the electronics, but wonder still if it is a fuel delivery problem.  Is there anyway to bypass the fuel system and pump fuel directly?  Have you tried using starter fluid to see if it responds?

Cody,

Yes, Stradivarius was known for his violins, celli, etc, but he was a versatile luthier (I like that word) and made different instruments.  There are several guitars and mandolins still in existence.  Although his washtub bases were considered the best of his time, I can't find any documentation for those.

http://en.wikipedia.org/wiki/Stradivarius

The bottom of the article lists the instruments.  I will not even mention his awesome jump shot.  

[blue_goose]

If all of the voltage is there it is going to be a fuel problem.  Check the filters and see if they are still full, if so give it a shot of eather and it may pick up.  If not full of fuel check your one way fuel valve.  The solenoid  won't keep it from running.
Jack

[Dallas]

Ace,

To check fuel pressure, go get a mechanical oil pressure gauge (at least 80 psi) at your favorite auto store along with a bushing to transition from 1/4",(on the fuel filter housing) to 1/8", (on the gauge) and plug it in to one of the unused outlet holes on the secondary fuel filter.
at idle you should have 15-30 psi and over 1200 rpm you should have around 50-80 psi with a steady reading.
If it wavers or drops on acceleration, you may have a collapsing fuel line. If it wiggles a lot, look for a worn spot in a fuel line, or a loose/broken fitting.

Sorry I can't be of more help.. I know nothing of DDEC and plan on never learning...
As an aside, it's strange how Don can get the MUI 2 stroke DD"s to pass EPA, but with all the electronis, DD couldn't do the same.

Dallas

[Sammy]

Ace, pull out R7. It's the fast idle relay and it ties into the TPS circuit.Start your bus and see what happens and let us know.
IF you still have same problem:You said you hava a ProLink. With the engine NOT running and the ignition switch turned ON :1. What are the TPS readings at idle - no pressure on accelerator pedal and 2.What is reading at full fuel - pedal held to floor?
3. They should also change gradually as pressure is increased slowly on accelerator pedal with no "dead" spots.
Let us know.

[Blacksheep]

Sammy did the TPS test and at idle position the reading was 27 and at mid way it was holding steady as my foot would allow and at full throttle it read 190. I have not pulled the high idle relay but will try that!
I found today because of yesterdays frustration that I left the main switches on and the batteries are too low to start the bus. They are charging right now and should be good to go by morning!

Ace

[Sammy]

Ace, idle reading is good. Book says 20-30.
Book says full fuel is supposed to be 200-230 but 190 should be fine.
Your problem is not at idle or full fuel, it's intermittent  - so now you can leave the TPS alone.
Make sure 12v side is charging fine too. Remember DDEC 2 is a 12 volt system. Those yellow and red power wires (Prevost) could get mixed up when disconnecting and connecting them at the batterys.Double check them if you disturbed them - connectors on ends or wires too.
Let us know. 

[JohnEd]

Finally, back to the battery box.   As if I knew squat.   Really like that trouble-shooting philosophy of "eliminating various 'things' as the cause will eventually lead to a solution".  Except where you have multiple failures...then you need the pro.  Complementing you here Sammy.

Good luck, Ace

John

[gus]

Ace,

I know nothing about DDECs and don't want to. However; I do know that relays/solenoids and corrosion don't mix.

If you find the slightest bit of corrosion at any connection to a relay/solenoid be sure to clean both contacts very well. This is very important because some relays/solenoids are just strong enough to hold and if the voltage/current is reduced ever so slightly they won't hold, or always work in the first place.

Sometimes just unplugging and replugging will make it work again for a while.

I just had this experience recently, very frustrating but simple to fix. Voltages all checked out. Took me five days to figure it out.

[cody]

Lin, you'll need to go further than a wiki listing if you insist on being accurate, Antonio was a master luthier and no mandelins or guitars are credited to him, he did have other instruments come out of his shop but his two sons and various other workers in his shop were credited with creating some fine instuments such as early forms of guitars, and what could have been described as mandolins but these instruments were the products of other artisans in his shop not him, but Antonio was a specialist that concentated on his cellos, and violas, and violins, the idea of him creating a washtub bass is laughable, what you have to realize is that he was the driving force that created some of the finest instruments that came out of that area but he didn't work alone, he was the master luthier in a shop that at times were reported to have as many as 75 people working on various projects at any one time, also the stratavaious name was assigned to almost any instrument that was imported from some of the european countries up to around the mid 1880's when the name couldn't be used anymore, for many years it was used to describe a style of construction and was misinterpreted to be from the stratavarious studios.  If you would like to find other information on his shop one of the foremost experts on his work is lou stiver, lou stiver studied his approach to instrument construction for many years and is concidered one of the leading experts, lou's specialty is mandolins but he is often asked to authenticate instruments accredited to the stratavarious studios.

[Hartley]

Ace,

I have a stupid idea.. It's so off the wall that I wouldn't normally have
thought of it especially if I was frustrated.

Take the batteries completely out of the bus. Ground all the wires to chassis
ground and let them sit for about an hour.

Go back to the engine area and install a new braided heavy duty grounding cable
from the engine block to the frame.

Get a fresh set of batteries from somewhere for test purposes and install them after charging them properly. Do NOT hook the charger to the batteries while they are connected to the bus systems.

A sad note is that 99% of the portable battery chargers put a.c. components riding on the charge voltage. 30 or 60 cycle and harmonics can raise hell with electronic engine systems.

Install new batteries and hook everything back up making sure that the Negative cable is the very last connection.

Hopefully this will reset the ddec system?

Try it and see if it will run.

I also heard a while back that some DDEC system equipped buses had a lift pump installed inside the fuel tanks that came on and provided basic flow until a certain pressure was available at the engine before the ecu would let the engine have more fuel during startup. I don't know if your setup has the lift pump and if it doesn't then there could be a flow problem and the engine ecu isn't seeing fuel pressure or flow enough to signal the ecu to get out of start mode and into run mode.

One of the DDEC guru's could probably research the "start" and "run" modes and what sensor tells the computer to switch modes.

It is my understanding that a computer controlled engine will not saturate with fuel on startup because the computer cuts down to minimal fuel mode to avoid loading up and smoking at start. After all the self checks are done it should switch to "RUN" mode.

Like I said.. Just a WAG.....

[JohnEd]

Dr. Dave,

Yours wasn't a WAG or a SWAG either one.  Just good solid advice.  Grounding has always been a serious issue in automotive in general and RV in particular.  IMHO and experience.  Bad connections in the ground and B+ both will "develop" any noise that is being generated.  There are supposed to be capacitors inside those ignition modules for cars but they fail and go unnoticed till the hapless guy replaces his alternator and then the car won't run or similar problems are unmasked.

I agree with all you said except "all new batteries".  I think you could go through the system as you suggested and "see" if the problem resolved and then that would spare you the bat purchase expense.  Then replace the bats, perhaps. 

You can test every one of those joints and the braided cable armed with a decent digital VOM, electrical theory you get out of High School Physics and just work on the areas that need it.  I recently looked at my gen dc start system just for GP.  I am getting 6 volts to the gen starter out of 12 and the feed line is 20 feet of 00 cable.  Work to do on the connections.

Enjoyed your post Dr.,  Thanks ,

John