I took a trip from Colorado to Minnesota a couple weeks ago in my Durango. It ran great the entire way there and for most of the trip. I was parked outside a friend's house overnight, went to start it, and it wouldn't start. The battery and starter are fine. I switched out the fuel pump relay and it wouldn't start. We tried to push it to get it off the street and into the driveway. After we got it in the driveway I tried it again and it fired right up. On the way back to my grandparents' house it died on the side of the road. I took it to what little of the shoulder there was (basically some bumpy turf before it goes straight to ditch). I tried to start it and it fired right up again. Took it to my mechanic out here and he replaced the fuel pump (he's a family friend and I trust him to work on my stuff). It started and ran great so I took it to my grandparents' house. After I got it there, it wouldn't start again.

I did notice that when I try to start it, the fuel gage does not move and it will display "no bus" where the mileage is supposed to be displayed on the dash. My mechanic thinks the power control module or PCM has stopped functioning. Just wondering if anyone can confirm or deny his suspicions?

 

i am no pro mechanic by any means but just reading the problems and fixes here on this site i have learned quite a bit. take my advice for what its worth (not much) but hey you never know.. it sounds to me like you may have a bad battery or a crankshaft positioning sensor. maybe someone on here has a better solution?

 

It's not the battery. It was replaced in December when I bought the Durango and the dash would not display "no bus" if it were the battery. I suppose it could be possible it is the crankshaft positioning sensor, but I don't know anything about that part.

 

if you are seeing the nobus error code in the odometer window that means that there is no communication with the PCM, i would start by checking the connections in the engine bay at the computer myself. however there is a sensor that can go bad and ground out the bus stopping the PCM from communicating but i cant remember what it is, im sure master tech will chime in on that one

also while i tend to agree with you that your battery is NOT the problem, it is possible to buy a bad battery, just because your battery is only 8 months old does NOT guarantee that it is good, these trucks are VERY picky about batteries,


for the fuel pump next time it wont start crawl underneath with a rubber mallet and bang on the bottom of the tank, if it then starts your fuel pump is failing

 

I'm wondering if maybe my fuel pump and my PCM were going bad at the same time? You could bang on the tank and it would start. Now, after replacing the fuel pump, you can't do that anymore and the no bus indication comes on whereas it didn't before. And we tested the battery- it is still good according to the tester.

 

Sounds like the PCM. Battery may not have been big enough. I replaced my AIC, PMC, TPS, cleaned the TB all because of the symptoms you describe to no avail. I knew the battery was good because I had just replaced it before having problems. Turns out, my battery was not big enough, even tho it was the exact same size as previous. My 2cents.

 

But my point is that it has worked fine for 8 months and would not cause the "no bus" signal. I got the battery that goes with the 5.9 V8- made the store clerk at Interstate batteries triple check.

 

I think it could be a bad connector on PCM, check connectors that they not are bent or something like that.

 

the battery will not cause the no bus issue (or at least i have never seen a case where it does) however the battery load test is no good on these trucks, they are so picky that a battery can pass the load test and still be bad enough to not run these trucks correctly.

as i said above check the connections at the PCM and the fuel pump relay and get back to us with any results

 

Rick checked PCM connections and says they're all good. He changed the fuel pump relay and it still comes up with no bus. The PCM part should come in in a day or two. I'll let you guys know if that solves my problem so I can go home to Colorado! Was supposed to be back last Wednesday - surprisingly, boss man is understanding and not mad...