Engine/Transmission (1998.5 - 2002) I could use some problem solving - truck won't xxxxx

[rweis]

Running normally for years now. Pulled the 5er RV last weekend about 100 miles one way. Ran fine. Had a little RV work to do last day or so, did that. Went to put RV back into storage lot and it went to s...



Running O/D out because the speed limit is 40 and did not want transmission to shift into O/D (DTT transmission 89%). Turned down to where the stroage lot is and it started running extremely rough. Missing ignitions the whole thing. Shut it down. Got Smarty out to check codes and smarty could not communicate. Did the key on/off got P 622 743 753 1765 1694, NO ECM codes. Got it started put RV away but more symptoms are in P,N idle is 800, in any gear idle is 1200 or so. Doesn't matter the gear, accelerates to 1200 by itself. Put in P or N and idle goes right to 800.



When I recranked it it ran smoothly, no misses etc, let it idle while buttoning up RV, smooth. Put in D to leave storage lot, right to 1200. THere is a long road from the storage lot so let it do it's thing, 1200, shifts from 1 to 2, 1200. Put in N, 800.



Drove it home, parked it pulled codes again. P 622,743,753,1765,1694, NO ECM codes. Tried to start it, would not start. Cranks well, would not start.



Ideas? 102k, DTT see sig,



Bob Weis

 

[MKinner]

I would check the ECM harness connector and make sure that it is tight. Also check and make sure the actual connector hasn't pulled apart, I've seen that happen. If all connections are good, i would take a hard look at the ECM since you stated that your smarty wasn't able to connect. .

 

[GaryOwen]

Wonder if it could be the Williams APPS? Might try replacing with OEM if you have one.



Gary

 

[AKAMAC]

With the problem showing up in D or R I would look at sensors that effect the PCM/ECM causing shorting between the two when in D. Maybe the pressure solinoid in transmission? Speed sensor at tail housing? I don't know but having the Smarty fail to communicate is strange. Maybe try unpluging the trans harness and check if the Smarty will talk. I love electrical gremlins! Mike

 

[rweis]

Well, today was another HOT one here in central florida.

However, NO rain today.

Got home and tried to start the truck, cranked right up.

Shifted through the gears, acted exactely correctly (ie in reverse & drive higher engine effort, but same rpm (brake on)).

Connected the Smarty, it had a little problem with the vin number right at first.

Reconnected the Smarty, loaded the stock ECM as advertised. Only the normal 1693 code.

Virtually everything worked as advertised.



MY take on it. Water in 1 or more of the 3 PCM connections, or water in the ECM connection, or water in xxx connection.



Next step is to take every PCM, ECM connection & ground apart and thouroughly clean it and apply dielectric grease to seal it.



I think the problem is lack of use and the daily torrential rains.



I bought a Suzuki Bergman 400 2008 super scooter to get to work (scooter = 65 mpg / 3 gallons / $12 / week vs truck = 16 mpg / 14 gallons / $70 / week). Difference of about $2500 / year in fuel + ultra simple maintenance (another $800 per year in maintenance supplies (fluid, tires, filters) + the obvious safety exposure issue of a scooter (potential life threatening).



The truck has been sitting in the driveway and only taken out about every 2 weeks for light exercise driving. Not enough driving to clear condensation of the recent daily rains from all the critical connectors (PCM, ECM, etc).



At least that is my first take. So I am going to clean and waterproof all the PCM, ECM, etc plugs I can find and see how it goes. I think the PCM area is the primary culprit (all the transmission codes), but I will dive in and clean them all (takes a couple of days I would imagine). 102k miles so no warrantee is involved and so I can get to all the "void" stickers and do them ALL.



Yesterday I had a terrible sinking feeling of "OMG" what the heck has happened. Called Rip Rook (one of the smartest diesel guys I know) of Source Automotive and got his thoughts "water in a major connector somewhere", "keep it dry and let it sit for a few days then try it again".



Today I was as elated as it was terrible yesterday. At least I have a plan, let's see if it works.



Thanks for all the ideas, TDR is probably THE best friend you will ever have (except your wife of course, wife then TDR in that order )



Bob Weis

 

[rweis]

I have not done anything to the truck. It has been dry for about a week now. Drove it about 4 miles same thing.



Had it towed home, dielectric greased all connectors, PCM, ECM, 2 up by the middle of the cowl, VP44. Actually they were already greased from years back. Checked for water in water seperator, no water all clear. Checked fuel pressure and flow, all good. Backup fuel pump works fine. Fuel was in the input fuel cavity of VP44, do not think that is it.



Smarty still will not connect - might be a KEY sign. I keep trying to get it to connect and it will not. I am going to call MADS or Bob Wagner and see what they think. Anyone know what a failed ECM acts like?



Where is the transmission harness plug?, so I could try that.



Bob Weis

 

[Jetson]

I had trouble connecting and reading codes once on my wife's Durango. It cranked a little slow also. Replaced the battery and then I could read the codes. But I ended up having to put a new ECM in it anyway because it would show codes when there wasn't anything wrong.

 

[Bob Wagner]

I am going to send an ecm free of charge to Bob to see if it fixes his issues.

 

[MAllen1]

I would clean your connectors. If you still have a problem, I would unplug all "piggy back" units and give it another shot. The way you explain your situation, it sounds like it could be one of those two.

 

[rweis]

MAllen1 -



I cleaned all the plugins, had dielectric greased them years ago, regreased them. They were all clean.



I do not run any "add on boxes" just the Smarty, which I put the ECM back to stock after the first episode once I could get the Smarty to connect to the ECM after the first episode.



Bob Wagner is sending me an ECM that will tell me if it is the ECM. Bob I REALLY appreciate your help tremendously.



Gary added to the old thread about the VP44 and heat. He measured the ECM container heat and it was way way high, close to the block temperature. The VP44 cooling concepts we did years ago probably apply here as well.



Whatever happens with the ECM it gets its own thermal blanket insulator from the block and its own bilge blower. I think I am going to name my truck like a boat, this will be the second bilge blower.



Thanks for all the replys and the HELP! I will get Bob's ECM and swap it and report back. The truck has sat for a couple of days and the Smarty still has zero idea of how to connect to the ECM. NO COMMUNICATION. If the Smarty is not communicating across the canbus, the ECM is probably not communication across the canbus either. I totally charged the batteries also just in case there was a low voltage problem, did not help.



Again, thanks for the help. It is a very sinking feeling when you baby these trucks like we do and have a problem that seems unsurmountable until you fire up the computer and log into TDR. BEST Darn $35 a year you will ever spend.



Bob Weis

 

[bmoeller]

We had an ECM blow on our ISX Cummins 2 weeks after we got the used truck. The ECM fuses were blown as well. Dealer replaced the fuses, and still no communication between the ECM and laptop, and the engine still failed to start, and the ECM controlled primer pump didn't run at start-up. They sent the ECM next door to Cummins and they did their diag tests. ECM was dead. Dealer was nice enough to pay for the repair and tow at their expense.

Best we can figure, is the truck was hit by lightning. We never had a welder near the truck, and it had started and run fine the day before.

 

[Gary - K7GLD]

HMMmmmm - looks like mostly transmission related codes, and lack of communication to the PCM (and between the ECM/PCM) - maybe a failed PCM instead of the ECM - or poor connections at the PCM?



Good luck!

 

[Bob Wagner]

ecm shipped

 

[rweis]

Thanks, looking forward to its arrival.



I need to move the RV with the hurricane FAY comming, and I REALLY need the truck to get that done.



Bob Weis

 

[rweis]

Swapped Bob Wagners ECM with the OEM ECM I had, she cranked right up. Smarty connected right away. I have not driven her yet, but seems to be fine. Thanks Bob Wagner!



The swap took some time to get to: the college I work for is in the middle of orientation for the biggest incomming class we have ever had, Hurricane Fay had to get out of the way (I hate to wrench in the rain), had to work in an anniversary (our 9th) trip to the beach, wife's dad (88 yo) is moving in with us in September, and the normal in's and out's of day to day life.



What do you think about? -



I am going to put the ECM on 1" or 2" nylon standoffs (from Home Depot) to get it away from the block. or



I took out my OEM fuel fillter years ago, make a bracket that would go from the OEM fuel filter bolts in the intake manifold to the ecm side attachment bolts in the block, and attach the ecm to these "struts" out in mid air several inches from the block and in the general airflow under the hood. Sort of a square corner U shape bracket, but GET THE ECM AWAY FROM THE HOT BLOCK! Idea worked for the VP44 (we took air TO the VP44 with the bilge blowers and used a thermal blanket between the VP44 and the block).



Some variation of the above, but get the flippen electronics away from the heat, doh!



Bob Weis

 

[Gary - K7GLD]

My heat-shielded ECM temps are running a consistent 30-35 degrees above ambient down the road - about 140 max on a 95 degree ambient after engine shutdown from heat soak - I'm sure the VP-44 bilge blower is providing significant temp reduction for the ECM too, with the general cooling to the driver side of the engine - will try watching what happens with the blower switched off at shut down to see the difference...



Glad you have your problem corrected!

 

[ROADWARRIOR]

You guys have a link to your ecm / vp cooling threads?



One question on your thermo blanket between the block and vp44, do you have any rust issues? I put some on top of a portion of my exhaust and it pitted the heck out of it.



Thanks,

Dan

 

[rweis]

Here is one of the threads https://www.turbodieselregister.com...emperature-input-vp44-80-100-your-inputs.html



You need to know that there are about 4 or 5 threads that cover probably 3 - 4 years of experimentation, bread boarding, measureing, re-breadboarding, re-measureing, testing, discussion, more measureing, more testing. You get the idea. It was probably some of the most intense "experimentation" trying to correct what Dodge engineers screwed up. Like strapping an ECM (engine computer module) to a hot very large block, and expecting it to work well, for many many years, in a truck used for heavy hauling. RIGHT.



Basically, for the VP44 - fuel coolers, fuel tank modifications, fuel line modifications, heat shielding, forced air cooling.



Experimentation on the ECM really has not taken place yet, but same principles apply, get it out of the harm's way of heat.



There is a thread about the APPS too. Much more recent, but really brilliant problem solving by one of the members just looking at a picture of a circuit and knowing what it did. That information pointed the experimenters toward a really simple, extremely cost effective replacement of the Dodge APPS. Also heat related failure by poor Dodge design.



I am going to hang my ECM out in the underhood air mass on brackets. Gary measured the underhood heat for a while and it was consistently +10* from OAT. That would seem fine (max OAT I have seen 105* +10* = 115*, not too bad). When I get the brackets made I'll try to get pictures so you can see what I did.



Functioning hood scoops / fans are looking better and better.



Anyhow, long story and many threads about cooling the VP44, not too many about cooling the ECM. APPS needed some help and that one was solved as well. PCM should be fine over on the firewall passenger side.



Bob Weis

 

[rweis]

First long RV pull with replaced ECM.



Worked flawlessly, Thanks to Bob Wagner! Exactely what the problem was.



Now, to keep this ECM cool I decided to mount it out in mid air between the fender well and the engine block and then check it's temperature and see how it goes.



I have moved the OEM fp long ago but left the hole sealed up with the fp plate. I cut the little pointed ear off on the radiator side of the OEM fp bracket (Dremels are GREAT tools!).



I turned the ECM around so the plug is toward the engine because there is not enough wire harness to keep the ECM plug toward the fender.



Then I zip tied the ECM to the empty fp mounting hole on the driver's side front (toward the radiator) of the OEM fp bracket (after I cut the little pointed end off so the ECM will fit better).



Then I suspended the forward end of the ECM from the bracket that holds the high pressure injector lines up toward the VP44. That bracket is L shaped and very sturdy. I did not zip tie to the injector lines or the VP44 return fuel line. Just vertical suspension from the injector line bracket. The forward mounting hole on the ECM aligns very well with the forward suspension point.



I temperature checked the body of the ECM a couple of times. Conditions were 90* ambiant. Case of the ECM was 125*. I checked it 3 times and it was very close to 125* each time. This is pulling the RV (13k) @60 mph. The temperature tends to tell me that the ECM generates some heat because the under hood heat was 100* - 105* (which again verifies Gary's readings of under hood heat ~ 10* above OAT). If the ECM was strapped to the engine the block would have been 180*+ and I am sure the ECM would have been significantly hotter.



I am going to leave it suspended in mid air for a while and check the ECM case temperature a couple of times throughout the year. I will report back here as the seasons roll along.



Bob Weis

 

[JLandry]

The temperature tends to tell me that the ECM generates some heat...

Bob,



I'm sure your right.



I was recently reading the book "Computerized Engine Controls" by Steve Hatch and Dick King, in it I learned that over the years various vehicle manufacturers have used different methods to cool hot ECM's. Some have been mounted with intake air flowing over the computer (Chrysler in the 80's) while one I read about even had fuel routed through internal passageways within the ECM for cooling (can't remember which manufacturer used that).



It seems strange that Cummins would choose to bolt our ECM directly to the block.



John L.