I have a 1996 3.9L v6 Dodge Dakota that has never given me any issues before. Recently, after not starting it for about a week, I tried to start it and it would only crank. I have experience working on other cars but this truck is mostly unfamiliar to me.

What I have checked out so far:

-Cleaned up battery terminals and they are nice and tight.

-The check engine light comes on when I put the key in the "on" position, the light goes away after about 10 seconds.

- I tried to get the truck to display its codes by inserting the key and turning it on and off 3 times and the check engine light just remains lit up solid for 10 seconds and just shuts off.

-I can hear the fuel pump turn on for a second when I turn the key to "on"

- The tach does show fluctuating rpms when I am trying to start it.

-There is a valve on the fuel rail to hook up a fuel pressure gauge. I had someone turn the key over while I was pressing down on the valve and fuel did spray out.

- I checked the ASD fuse and ignition fuse and they both check out good.

- I swapped the ASD relay with a couple of other relays and still no start.

- I hooked up a spark plug to the coil, grounded it and cranked it over. I saw no visible spark.


- I replaced the coil with a new one from the parts store and it still will not start so I will be returning the coil.

- I tested the wiring to the coil with a test light. It is receiving power(green wire) when cranking. However the trigger ground wire should be blinking when cranking and the test light is just solid on, even when I am not cranking.


From my understanding, it could be: (please add to the list)
Crank position sensor
PCM
short in a wire somewhere

I really appreciate any help with this.

 

well being a 96 its an OBD2 system, so you can use/borrow/autozone or somehting can usually pull codes with a scanner if you cant get one . if it dosent its a bad sign

 

man those 3.9s are horrible motors. Im having the same issue in my 90 dak right now.

 

The 3.9 has its limitations, but is by no means a "horrible" motor. Your '90 Dak is twenty-four years old and entitled to develop some issues. I suggest you learn to deal with them or buy a newer truck.

If the following paragraph doesn't produce results, you need to take steps to rule out "The Splice". If you don't know what I mean, check the Troubleshooting sticky. Amongst other things, it describes the A14 splice in three red/white wires going to one that supply the coil, injectors and fuel pump. "The Splice" can disrupt starting intermittently or permanently, depending on its condition.

You do mention the fuel pump runs for a second when you turn the key. This tends to point my attention away from "The Splice" and towards the crankshaft position sensor. This flat, ring-like item lives under the distributor rotor. If the PCM does not receive a signal indicating engine rotation from the CPS within two seconds of start-up, it (the PCM) takes out the coil, injectors and fuel pump by deactivating the ASD relay, which has the same effect as a bad "Splice" (kills the engine). The idea is to avoid flooding the engine. Unlike a carb, the injectors actively spray fuel into the cylinders at 30 psi as long as they are supplied by the fuel pump. This could amount to a lot of fuel in a short time if you don't have ignition. Sounds to me like your PCM is aborting the start sequence due to the lack of a CPS signal. It is not unheard of for the signal to come and go, especially after jiggling the distributor cap and rotor around. Eventually, it stays gone. Incidentally, the 5.2 liter has an identical ASD system.

Bottom line: at this point, I'd replace the CPS.

 

Could be your neutral safety switch, I was having a similar issues with my 96 Dakota 3.9l that switch was 90$ on rock auto, I wasn't trying to pay that so I bypassed mine, I did this by removing the NSS on the clutch pedal and wiring up the hot side of the switch using 2 wires and a 25 amp fuse for safety, this fixed MY particular issue and I had to share, the ignition wiring looked terrible on one side by the fusebox by the battery, so I rewired that going to the solenoid on the starter, but since yours cranks but won't start, I was working on a pathfinder once had the same issue, could be your intake gasket, or something with your vacuum, it's not fuel, not spark, could be vacuum. Hope this helps

Also, if your inclined, Ebay has obd2 scanners for around 20$ mines really helped me.

 

First, this thread is 7 years old..... I would hope he has it fixed by now.

Second, the neutral safety switch failing would give you a no crank condition. His cranks just fine.

 

I addressed that. With my personal experiences on what I thought it could be, thanks for your wonderful input on the issues at hand.

Never know, there could be someone out there not as great as repairing things as you are that could maybe be helped by what I posted, I personally have found posts 10 years old from others that have helped me out. All im trying to do is help others friend!

I've lurked boards for a long time and I'm just trying to help.

 

Someone with the same issue could find the thread the same way you did too. Either that, or the 100 or so threads on pretty much the same topic that have cropped up since then.

In case you weren't aware, bumping truly ancient threads, is considered 'bad form' on forums. Please don't do that.

 

sorry I did not know that, on my phone it showed up on page one, this was before I realized there was 680 other pages, my apologies, I'll be more careful in the future, I'm new here.

 

No worries. We were all new at one point in time.

Posting from a phone, watch auto-correct as well. It can make for some truly astounding errors in wording.