iv been veiwing these fourms for about a year now fixing my truck and jsut now decided to join. one of the reasons is that im at a loss on whats going on with my truck and would really apperciate some help. im sure this problem will stump alot of people on here.

i have a 99 dodge ram, 5.9L v8 magnum, 1 cat coverter, no mufflers.
for about 5 months now the engine has been shutting off at random with no warning. no Check engine light.

*when the engine does shut off it will not turn back on right away the starter just keeps turning. it will eventually start back after it sits for about 5 mins. the temp is fine, it will do this after 10 seconds of driving or 1 hour of driving. it will do it when its cold or warm out.

*some times after its been sitting for 2-6 hours it wont start unless i leave the key in for about 5 mins.

*the last time it did shut off was 2 weeks ago except for today which gave new symptoms. i went to a store about 3 blocks away. got back in it and it wouldnt start ( nothing new so i just left the key and waited 2 mins) after i got it to start running it was idleing rough like it some times does and when i put it in reverse it was trying to stall but when i gave it gas it was keeping it alive while still trying to shut off, put it in drive and went about 5 feet and it died couldnt keep it alive.

* when im driving at 45 mph with out my foot on the gas my rpms are at 1500, when i give it some gas for an upcomming hill the rpm will go up to 2000 then imediately go down too 1800 giving the same amount of gas before i hit the hill, still going down a hill, and will also do this going up the hill. i don't know if this is related to the stalling but im giving as much information as i can.

*also the tranny shifts rough. 1st gear grinds when given to much gas.


iv checked the fuel pressure while it was idling rough and it was 50-55 psi which is good acording to the book. iv also replaced the distributer and rotar, the spark plugs are all fine, the wires are only a year old. iv also taken apart my throttle and cleaned everything and replaced the idle air control and throttle position sensor. checked the fuses and all are fine. and the air filter is brand new.

and this is where im stuck i have no idea what this can possibly be its probably something stupid yalls help would be greatly appreciated.

 

I'm gonna throw this out there, have you fixed the plenum yet?

https://dodgeforum.com/forum/2nd-gen...um-thread.html

 

Sounds like your battery is becoming disconnected, your grounds are messed up, or there's a short somewhere. The fsm in the DIY section will tell you where those grounds are and I'd check that first, actually I'd check the battery and make sure all of the connections are firm and tight.
My friends truck did the same thing and we found out it was the battery terminal slipping off long enough to kill the battery

 

As said, check the plenum. If it's blown and the cat is partially clogged, it can be worse when the engine is up to operating temp. The other thing is , you have classic symptoms of a bad crank sensor.

 

hmmm interesting never herd of a plenum till now i will have to check that out in a few waiting for my dad to get home to get that father son "bonding time" in lol iv checked the battery and the terminal connections are fine, when it does shut off al lthe electronics stay on and i dont notice the radio turning off for a split second, i also forgot to mention that today when it did waht i mentioned above i took the iac wires off and it started up and i plugged it back in and was able to drive it back home. this was also 10 min after trying to start it up and just tried something random i don't know if it was that "off chance" it started when it was removed and it had nothing to do with it or not.
i was also going to repalce the crank shaft position sensor but could never find it my book does not really show where it is does some one know of where a picture or video is of some one showing exactly where it is?

 

Crank sensor is on the tranny housing, behind the passenger side head. Between the head and the tranny dipstick tube. Two bolts, use a mirror and flashlight to get a bead on it.

 

The two screws have an allen head (1/4" i think) and a hex head, Hard to see as referenced by zman. Small hands work best - watch sharp edge on heat shield on firewall.

 

i was gonna say the same thing either sensor or a grounding prob. but the ground prob dont make sense totally if its just sitting not moving then it will start 5 min later, without hittin a bump or anything. let us know what the sensor does.

 

okay i replaced the sensor, was a pain to replace but i did it. took it for a test drive and it ran fine, it is still doing the rpm drop going up a hill when i give it gass goes up to 2000 then drops to 200 within a split second. im not sure if this is right or not i didnt notice it last year. i will let yall know if it shuts off again, i did forget about the time it shut off on my going up a hill about 3 months ago, i was going about 55 and it shut off, as i pull over the the side of the road it turned its self back on with out the starter turning on. this was probably a big thing to forget to mention lol also the bolt size is 1/2 inch. and is works better with some one on the bottom telling the person on top where the guied the ratchet.

 

your issue going up hill sound like the start of a sensor/ solenoid problem with your transmission could be an other issue thou. fix one issue at a time to avoid confusing symtoms check your plenum and let us know whats up with it, it could cause you alot of issues in the future if left untouched.