i am having a problem on my 97 dodge 1 ton diesel.

it will run fine until:

the tach jumps all over the place up and down and then if i am doing 70 MPH or so it will kick out of overdrive and then back in and then back out. if i turn the overdrive off when it acts up again it will kick the switch back on itself.

also some of the time the lights will dim way down for awhile maybe 10 seconds or maybe 3 minutes and also when the lights do that the volt gauge goes down to like 12v.

and when the lights and volt gauge do that the GEN light will come on some of the time and only a couple times the CHECK ENGINE light. and most of the time when the GEN light came on the TACH was reading 0.



anyone have any ideas?? i was thinking maybe the ALTERNATOR??? but whatever it is its one thing as it runs fine until the tach acts up then the other stuff happens.

any help fast would be great.

thanks,
joe

 

I bet Crank position sensor. the alternator is controlled by the ECM and the ECM uses the CPS to tell if the engine is running. if the ECM can't tell the truck is running you will have no tach, on overdrive and no alternator.

 

Mine lost all that stuff before. No A/C, tach, speedometer, Alternator quit charging, and lost overdrive. Changed the Crank Position Sensor and it fixed it. You might change that to begin with since its an easy change.

Eric

 

Im having the exact same problem right now dude.Im gonna get a crank sensor tomorrow.Just make sure you check the clearance before you change it out .It should be set to .050 according to the hanes manual.Or something like a credit card.Does yours do it at idle in park as well sometimes?

 

yes if i pull off the road it will do it in park or nuetral. but most of the time if i pull over and put it in park it will clear up for a moment but not always. and also if i floor the truck the lights will get brighter for a second and it will clear up.

what tools are needed for the sensor and were is it located?? as i am on the road in Laramie, WY and have limited tools and its very very cold.

thanks

 

It is located down on the top passenger side of the vibration dampner on the crank. You are not supposed to use a steel feeler guage when you set the clearance as well, brass. Also check our the wires going into the connector they can crack and cause an intermittent problem as well.

 

ok guys. i was heading to the only town around that had one to get one and it only did it a couple times in like 300-400 miles. then all of a sudden the truck seemed to like go into nuetral. and now it won't go anywere. it won't go into any gears. i am sitting on a 6 percent grade uphill right now and it will sit in park. i have tried to put in any gear or reverse and it won't do anything. but the funny thing is it will go back into park and lock.

anyone have any ideas?? i am 1,300 miles from home stuck in Utah now. my motor blew in my one dodge so my dad and brother in-law drove 900 miles to get that truck and i bought this truck and now having these problems with it. i need help to get on the road. the tranny in this truck is an ATS tranny that is supposed to have 30,000 miles on it.

could it be something electronic thats not letting it go into any gear or is the tranny shot or what??

HELP QUICK!!!!!

thanks,
joe

thank god for wireless internet and laptops. as i am sitting in my truck as we speak on the interstate.

 

All I know to tell you is let it cool off, and try it again. Is it full of fluid? I have had a line blow off of mine before. Good luck

Eric

 

it wasn't running hot. only around 200-210 for a temp. and yes its full of fluid and the fluid is still clear as it looks new. no sign of heat or anything.

it doesn't make sense. is there something electronic that will cause this or what??

joe

the motel is costing me an arm and a leg here to stay.

 

you could post this in the help section in hopes that more people could see it also. sorry thats all I had to offer good luck

 

i would but only 33 people are viewing on there and 133 are viewing on here.

thanks,
joe


what electrical wires should i check to see what could cause this??

 

i just had shop come here and hook up a scan tool to the battery. and it showed 1150 cranking amps but only 14% charge. and he thinks its the alternater. could it possibly be that??

thanks,
joe

 

ok update. the alternator isn't the problem. tried that and reseting the computer and that didn't work the shop said.

the engine and trans aren't spitting out any codes of any kind.

the scanner says that the engine is at -40*F and the engine isn't running. thats when the engine is running and heated up.

does anyone have any ideas???

the shop is trying to find a friend with a computer so we can try that and see if that helps.

i was wondering on the Crankshaft Position Sensors now can they go out totally or can they be reggaped and cleaned like a spark plug??

thanks,
joe

 

the sensor is like 80 bucks isnt it?For the amount of money youve spent already just put one in.Remember the sensors talk to the pcm and if the tach reads 0 the brain thinks the truck is off

 

the tach wasn't reading 0 it was ideling around 900 or so.

but i am on my way to get the sensor its $150.00 and i am going to get two new batteries also.

any other ideas??

thanks