97 Ranger 4.0 still runs/won't run/runs

[ak47smurf]

Greetings again. I had posted about 6 weeks ago concerning my son's Ranger failing to start when things got humid. Checked the coil, (metered-out good), replaced the plugs and wires, (I think they were the originals with 140k on 'em) and everything was great...until last night. I parked the truck and came back out 2-1/2hrs later. Engine cranked over just peachy but no start, no cough, no nothing but the turning over engine. Checked it again this morning, same results. Got home from work, put in the key and it started right up. no matter how much twisting and turning with an inspection mirror, I can't see the Cam Position Sensor at the back of the engine and somewhere I thought that I read that non-California models didn't have a Cam Position Sensor. Crawled under and took a look at the Crank Position Sensor, doesn't look cracked or damaged but appears to be awfully close to the balancer, (there are 2 score marks on the balancer from where a 2 pointed extension on the sensor looks like it rubbed against the segmented part of the pully). Anybody have any ideas/suggestions short of having the truck exorcised? From what I've been able to read/gather, the Crank Sensor could prevent the engine from running but the Cam sensor generally doesn't...is that a reasonable assumption?
Thanks in advance.

 

[289-tiger-]

Greetings again. I had posted about 6 weeks ago concerning my son's Ranger failing to start when things got humid. Checked the coil, (metered-out good), replaced the plugs and wires, (I think they were the originals with 140k on 'em) and everything was great...until last night. I parked the truck and came back out 2-1/2hrs later. Engine cranked over just peachy but no start, no cough, no nothing but the turning over engine. Checked it again this morning, same results. Got home from work, put in the key and it started right up. no matter how much twisting and turning with an inspection mirror, I can't see the Cam Position Sensor at the back of the engine and somewhere I thought that I read that non-California models didn't have a Cam Position Sensor. Crawled under and took a look at the Crank Position Sensor, doesn't look cracked or damaged but appears to be awfully close to the balancer, (there are 2 score marks on the balancer from where a 2 pointed extension on the sensor looks like it rubbed against the segmented part of the pully). Anybody have any ideas/suggestions short of having the truck exorcised? From what I've been able to read/gather, the Crank Sensor could prevent the engine from running but the Cam sensor generally doesn't...is that a reasonable assumption?
Thanks in advance.

Intermittent problems like that will drive an owner crazy. Exterior temperature or humidity differences would lead towards vacuum or intake leakage. Check that the system is tight from the air filter box to the throttle body and all vacuum lines are tight. Check the basics on the electrical system, a bad plug wire to fuel pressure issues could be a problem. Take one step at a time and good luck.

 

[Earl43P]

You are correct, Crank sensor = spark, Cam sensor is for injector timing.

You could also verify the PCM Power Diode isn't loose.

"(there are 2 score marks on the balancer from where a 2 pointed extension on the sensor looks like it rubbed against the segmented part of the pully)."

If that is your way of saying the crank sensor has been touched by the teeth, replace the crank sensor. It should never touch.

 

[Snurfer]

i had the same problem for about a year. the failure was intermittent and i could never get it to fail at the shop. my problem ended up being a bad fuel pump that would turn off and on when i shut down the motor. started up fine in the morning, went to get fuel, filled up and it would crank no problem but wouldnt fire over. just my 02 cents. get a fuel pressure test gauge and next time it fails put the gauge on it and see what she does.
hope this helps

 

[98blownranger]

I would of thought it would of been the plugs. do you have any codes? does the motor turn over? you could have a bad ground. start with the things you should do. IE fuel filter,oil change air filter. you could try cleaning your MAS. none of those should cause the problems but they all should be done.. I see it does turn over... do you have spark or fuel at that time. that will cut your work in half if you can find that out.

curt

 

[jasonl]

Well it sounds like you are completely losing spark or fuel. Next time it does it pull one of the plug wires at the coil and place it so the spark could arch and you should be able to hear it crack crack crack as you crank. If you got spark you could take the cap off the schrader valve on the fuel rail and push it with a small pick or something to see if you got fuel pressure. Of course if you have a gauge go that route. You can by a cheap spark tester at advance for probably under $10 and unhook a plug wire and check spark that way. Once you figure out which one your losing ( I am guessing spark ) you would have a starting point. Check for power to the coil etc....

I can feel your pain, I had a 95 Grandcherokee that would just die on my wife and leave her stranded. I would go to check it out and it would always start right up. I ended up getting it to do it and started wiggleing one conector at a time until I got it to start. It was the connector on the coil. I could wiggle it with it running and make it stall. Turns our a little plastic lock that held the wires in was cracked. Replaced the connector and it never happened agine in the 2 years we owned it. Crazy things can happen. Good luck

 

[tempforce]

all of the above, but consider how many miles you have on the plugs/ wires/ect. once you get the intermittent non start problem fixed. you need to do the required maintenance. the old parts are putting a extra load on the coils and electronics.
which will cause aditional problems later.