truck sometime will not start/ also dies sometimes

[noname_com]

Truck info 2001 2500HD 8.1L just turned 100,000 miles.

The truck always had a bit of a surging problem @ idle when I bought it in 2002 with 30 thousand miles on it. took to deal while under warranty and saif the slight rpm deviation was nothing to worry about. I also had the truck hook up to the computer at the dealer and found nothing wrong. 70 thousand miles later

I have a problem

after the truck sits overnight it cranks after the first revolution. runs fine to work about 20miles. During the day I sometimes have a problem with it cranking. It will just keep turning over and will not start.

I then turn off and remove key and wait 2 or 3 minutes and truck will crank fine. Sometime while in the middle of driving cruising sometimes 55 sometimes 70 it will die abruptly and the battery light will come on then the truck returns to driving normally.

I am sure its prolly a sensor but I have not had any service eng light come on. I also have a problem with the 4wd.

recently my abs & brake light have =been coming on randomly after turning truck off then on lights go out, then I started having a popping sound coming from the front end when I engaged 4wd hi about every 20ft I get a pop. Can this be a bad hub? and since the abs sensor is in hub could this be the problem witht he abs lights.

 

 

Anyways I have posed 2 questions here and ANY HELP would be greatly appreciated.

[Haulin' 8.1]

First question's answer is replace the crankshaft sensor and problem solved.

 

Second, yes it sounds like a bearing/hub. Raise the front end up and grab each tire at 12 and 6. Rock the tire by pushing in with one hand and pulling out with the other back and forth. Any perceptable play is unacceptable and the cause of your problem. Spinning the wheel by hand for a while to push the brake pad off then listening for a rough bearing can also point it out.

 

Vernon

[noname_com]

let me get this correct a crankshaft sensor will make it somestimes not crank?

 

I will check the hubs by trying the 12 an 6 mthod here today.

I have checked with the local parts house and they can get me a cranshaft sensor this evening

64.99 @ oreillys

 

Where is this stinking thing located. I read somewheres on this board it was located on the drivers side on the back of the head. Can any one be a little more specific.

I will take a gander when I am checking the hubs here in a minute

[noname_com]

ok went to try and locate this freaking sensor and I cannot even get my hand on the back side of the vavle coer driver side. I guess I will try and locate it from underneath when I jack it up to check the hubs

[Haulin' 8.1]

That's pretty specific, the back of the DS head covers less than a square foot of one dimensional surface area. But yes you will have to go after it from underneath. Take a stuby 10mm gearwrench with you. It goes down inbetween the block and the flywheel. All you can see is about an inch where the wire harness connects and the 10mm bolt holds it to the head. Pry it up gently and push or tap it all the way out, about 6-8 inches long and big around as a dime. What ever you do don't get in a hurry and break it off with some still in there. Spray some pentrating lube on it once it's loose and work it down.

[noname_com]

stealer said 225 for part and replacing, I guess will let them sweat their ass off.

I will be taking it in on monday to get it changed out.

 

The hubs, jacked up the truck under each wheel. Spun the whell to free the brakes spun the wheel couple more times the driver side had a little bit of s ound while spinning very muted though do not think there is a problem with the hubs. Both sides had no play in them at all doing the 12 and 6 method. so I am guessin an internal axel/front end problem great that just sounds expensive.

I will have them check it out at the shop.

 

Thanks for the help on here.

[Haulin' 8.1]

after the truck sits overnight it cranks after the first revolution.  During the day I sometimes have a problem with it cranking. It will just keep turning over and will not start.

I then turn off and remove key and wait 2 or 3 minutes and truck will crank fine.

<{POST_SNAPBACK}>

 

 

 

 

let me get this correct a crankshaft sensor will make it somestimes not crank?

 

 

<{POST_SNAPBACK}>

 

 

 

OK on this point I think you have the technical meaning of cranking confused with started. Cranking means the starter motor is actively turning the crankshaft in an attempt to start it which means the engine is running on it's own power. That being said not being able to crank it is usually due to a dead battery, bad starter or ignition switch etc. Not being able to start a cranking early model 8.1 is usually due to a bad crankshaft sensor. It also is the usual cause of dieing at random.

 

Have fun getting to know your truck this weekend. I'll be doing much of the same on my stuff also. Anyone have any tips on 21 year old Mazda fuel injection as it applys to Rotary engines? Good thing I've got the internet.

Vernon

[renolaw]

yes, the CKP is a PITA to replace-- i started this project and later surrendered it to my mechanic. I know when to bring in the expert. Got it done for just under $200 and it was ready before lunch. I had the exact symptoms last fall. Your tach will now actually work as intended and w/ greater sensitivity.

 

As for the suspension, i have a different question: Lift front off ground and rather than 6 and 12, try 3 and 9--- i get some slop/play here-- is this a function of the IFS and/or steering design? Looks like an idler arm is loose, but the mechanic says thats normal... hummm... Han an allignment and all is well... but that play is still there.

 

 

Now to get the driver side DRL bulb replaced-- cannot locate a good description to get at it and of courese those pesky oil cooler lines occasionally leak...

 

sheesh, its one thing or another...

 

mb