apologize first for long post, but i cant get a response in the other general forum(102 views, no replies) first i have an 02 dakota 3.9v6 5 speed. started showing signs of fuel pump or filter problem. changed entire assembly. still cutting out and losing power especially during acceleration or in a pull. worse when warmed up so i figure coil. drove it in yard(started fine) and changed coil, and TPS. reset computer and no start at all. checked fire, and no fire to plugs. put old stuff back on, reset computer, and still no start. changed cap and rotor bug along with pickup coil. still no start. wont even hit. now getting fire to plugs(checked by putting old plug in wire and grounding it. pretty blue fire. checked fuel pressure at fuel rail, plenty of pressure. still no start. wont even hit. engine cranks fine. has never thrown a code or turned cel on during any of this. its dead in its tracks. put back on all old parts, reset computer, and still nothing. after $400 worth of parts today, i am sick of it. any one having this problem? please respond with thoughts!!!

 

I know sometimes if the Auto Shutdown Relay (ASD) is bad, there is no signal to the O2's or fuel injectors and the truck will not run. A bad Crankshaft Position Sensor (CKP) can cause the truck not to run too. This is from the Dakota Service Manual:

AUTO SHUT DOWN RELAY
DESCRIPTION - PCM OUTPUT
The 5–pin, 12–volt, Automatic Shutdown (ASD)
relay is located in the Power Distribution Center
(PDC). Refer to label on PDC cover for relay location.
OPERATION - ASD SENSE - PCM INPUT
A 12 volt signal at this input indicates to the PCM
that the ASD has been activated. The relay is used to
connect the oxygen sensor heater element, ignition
coil and fuel injectors to 12 volt + power supply.
This input is used only to sense that the ASD relay
is energized. If the Powertrain Control Module
(PCM) does not see 12 volts at this input when the
ASD should be activated, it will set a Diagnostic
Trouble Code (DTC).
OPERATION - PCM OUTPUT
The ASD relay supplies battery voltage (12+ volts)
to the fuel injectors and ignition coil(s). With certain
emissions packages it also supplies 12–volts to the
oxygen sensor heating elements.
The ground circuit for the coil within the ASD
relay is controlled by the Powertrain Control Module
(PCM). The PCM operates the ASD relay by switching
its ground circuit on and off.
The ASD relay will be shut–down, meaning the
12–volt power supply to the ASD relay will be de-activated
by the PCM if:
• the ignition key is left in the ON position. This
is if the engine has not been running for approximately
1.8 seconds.
• there is a crankshaft position sensor signal to
the PCM that is lower than pre-determined values.
DIAGNOSIS AND TESTING - ASD AND FUEL
PUMP RELAYS
The following description of operation and
tests apply only to the Automatic Shutdown
(ASD) and fuel pump relays. The terminals on the
bottom of each relay are numbered. Two different
types of relays may be used, (Fig. 1) or (Fig. 2).
• Terminal number 30 is connected to battery voltage.
For both the ASD and fuel pump relays, terminal
30 is connected to battery voltage at all times.
• The PCM grounds the coil side of the relay
through terminal number 85.
• Terminal number 86 supplies voltage to the coil
side of the relay.
• When the PCM de-energizes the ASD and fuel
pump relays, terminal number 87A connects to terminal
30. This is the Off position. In the off position,
voltage is not supplied to the rest of the circuit. Terminal
87A is the center terminal on the relay.
When the PCM energizes the ASD and fuel
pump relays, terminal 87 connects to terminal 30.
This is the On position. Terminal 87 supplies voltage
to the rest of the circuit.
The following procedure applies to the ASD and
fuel pump relays.
(1) Remove relay from connector before testing.
(2) With the relay removed from the vehicle, use
an ohmmeter to check the resistance between terminals
85 and 86. The resistance should be 75 ohms +/5
ohms.
(3) Connect the ohmmeter between terminals 30
and 87A. The ohmmeter should show continuity
between terminals 30 and 87A.
(4) Connect the ohmmeter between terminals 87
and 30. The ohmmeter should not show continuity at
this time.
(5) Connect one end of a jumper wire (16 gauge or
smaller) to relay terminal 85. Connect the other end
of the jumper wire to the ground side of a 12 volt
power source.
(6) Connect one end of another jumper wire (16
gauge or smaller) to the power side of the 12 volt
power source. Do not attach the other end of the
jumper wire to the relay at this time.
WARNING: DO NOT ALLOW OHMMETER TO CONTACT
TERMINALS 85 OR 86 DURING THIS TEST.
DAMAGE TO OHMMETER MAY RESULT.
(7) Attach the other end of the jumper wire to
relay terminal 86. This activates the relay. The ohmmeter
should now show continuity between relay terminals
87 and 30. The ohmmeter should not show
continuity between relay terminals 87A and 30.
(8) Disconnect jumper wires.
(9) Replace the relay if it did not pass the continuity
and resistance tests. If the relay passed the tests,
it operates properly. Check the remainder of the ASD
and fuel pump relay circuits. Refer to 8, Wiring Diagrams.
REMOVAL
The ASD relay is located in the Power Distribution
Center (PDC) (Fig. 3). Refer to label on PDC cover
for relay location.
(1) Remove PDC cover.
(2) Remove relay from PDC.
(3) Check condition of relay terminals and PDC
connector terminals for damage or corrosion. Repair
if necessary before installing relay.
(4) Check for pin height (pin height should be the
same for all terminals within the PDC connector).
Repair if necessary before installing relay.
INSTALLATION
The ASD relay is located in the Power Distribution
Center (PDC) (Fig. 3). Refer to label on PDC cover
for relay location.
(1) Install relay to PDC.
(2) Install cover to PDC.

Here is some info from the manual about the CKP:

DESCRIPTION - 3.9L
The Crankshaft Position (CKP) sensor is located
near the outer edge of the flywheel (starter ringear).


OPERATION - 3.9L
Engine speed and crankshaft position are provided
through the CKP sensor. The sensor generates pulses
that are the input sent to the Powertrain Control
Module (PCM). The PCM interprets the sensor input
to determine the crankshaft position. The PCM then
uses this position, along with other inputs, to determine
injector sequence and ignition timing.
The sensor is a hall effect device combined with an
internal magnet. It is also sensitive to steel within a
certain distance from it.
The flywheel/drive plate has groups of notches at
its outer edge. On 3.9L V-6 engines, there are three sets of double notches and three sets of single
notches (Fig. 26).
The notches cause a pulse to be generated when
they pass under the sensor. The pulses are the input
to the PCM.
The engine will not operate if the PCM does not
receive a CKP sensor input.

REMOVAL - 3.9/5.2/5.9L
The sensor is bolted to the top of the cylinder block
near the rear of right cylinder head (Fig. 30). The
sensor is accessed by removing the right front fender
liner.
(1) Remove right front tire and right front wheelhouse
liner. Refer to Front Wheelhouse Liner in
Group 23, Body.
(2) Disconnect crankshaft position sensor pigtail
harness from main wiring harness.
(3) Remove two sensor (recessed hex head) mounting
bolts (Fig. 30).
(4) Remove sensor from engine.

I have read that when you replace the CKP you are supposed to use the original bolts from the old one to reinstall the new one, I don't know why, I think it is because the bolts have to be a specific length. I have no idea if any of this will help you. There may be more info on the ASD relay and CKP in the search function here. I have read other posts with similar problems to yours and the problem has been either the ASD relay or CKP.

Jimmy

 

Had similar issues with my 5.9 once....it would crank all day and never fire, went through everything u mentioned...plugs, wires, cap, rotor, coil. Long story short it turned out to be the crank sensor. I'm not familiar with the v6 at all but that might be something to look at

 

thanks for the replies. the relay in the pdc is marked engine. none are marked asd. and as i said, no dtc codes have been thrown through this whole ordeal. i have an obdII scanner and constantly use it to be sure nothing there. would ckp sensor go out all at once. i drove it to where it sets now just this morning. it started fine then nothing. since i cant start it, checked fuel pressure by cranking engine test, and went up to 45lbs with no bleeddown. checked spark at plugs and good crisp blue spark. but no start. will crank and crank, but wont even hit or spudder. does anyone by chance have pic of where ckp is located. i looked and am not seeing anything. again 2002 3.9v6 standard trans.

 

CKP is on the right side of the block, just above the right exhaust manifold and in front of the bell housing. It has a wire connector and it has 2 bolts holding it to the block and a rubber grommet around it. Sometimes the grommet wears out and the sensor gets wet, which ruins the sensor or makes the truck not start when it is damp outside. You have to remove the fender liner to get good access to the CKP.

ASD relay is not labeled "ASD Relay". I believe it is the relay in the Power Distribution Center next to the battery that is labeled "O2" or "Oxygen Sensor".

Up in the sticky topics on the 2nd Gen page there is a link to download a free copy of the 2001 Dakota Service Manual (2002 is the same). If you can get one of the download links to work, there is a picture of the sensor location on page 14-38. I can't cuts and paste the pictures from the manual, only the text. You might check with the parts guys at the Dodge dealer, they might be able to print out an expanded view of the CKP and its location/general area on the block.

Jimmy

 

thanks for the reply. i just found the service manual download and saved it. pics help! found the 02 relay and swapped it and still nothing. as i said, can hear fuel pump kisking in and tested good pressure. have changed tps, pickup coil in dist. new cap and rotor and new coil. have tested iac and map sensor according to haynes. tested within specs, and these threw code as it said it would so i know code reader is good. good spark, and fuel but no start. i know it has to be a sensor somewhere not sending good or any signal. but why no dtc codes. had a friend tell me that his durango did same thing exactly and it was map sensor, but i hate to keep throwing parts at it, and i cant see ckp sensor going bad all at once. what do you think?

 

I also say the Crankshaft Positioning Sensor. It's a cheap fix $30-$80 bucks and all you gotta do is pull off your passenger tire, take off any plastic engine guards and it's right where the engine meets the tranny. I was getting a horrible backfire and after changing everything BUT the CKP it finally stopped. And yeah it is possible to just randomly die on you.

 

CKP can be bad and not set a code. Same for a lazy MAP or bad O2/ASD relay. I thought there was a way to test a CKP, but I don't know the procedure, if it even exists. If this were my truck I would install a new CKP and see how it goes from there.

Jimmy

 

thanks for the replies! i will get one of those and get it changed and see what happens, but i still dont understand why it did not turn on cel or throw a dtc code, but i guess after reading, sometimes they dont. how hard is it to remove inner fender guard? hopefully you are not talking complete inner fender correct? i havent checked to see if mine has smaller splash shields or complete liner comes out. was your trouble like mine and on same truck model and engine size?

 

Mine is an 02 3.9L and the guards were just held on by those annoying freakin flat clips. ended up breaking like half of them but you really only need 2-3 to hold it on.