Dodge Repair/1993 dodge dakota 3.9 v6 not starting
QUESTION: I've tried a new fuel pump, fuel pump relay,ignition coil, I have cleaned the distributor cap and rotary button. I've pulled the number 1 spark plug to inspect for serviceability. The truck turns over but still will not crank. I don't seem to be getting any gas to the fuel rail. Would it have anything to do with the auto shutdown relay? I've also been told to check the voltage to the bottom of the coil, if so , what should the voltage be? The truck was running fine until I stopped and filled up with gas and then it would not start. Please point me in the right direction, as this is driving me crazy. Thank you.
ANSWER: Hi Randy,
Did you try for fault codes using the ignition key: "on-off-on-off-on and leave on" doing that in 5 seconds or less elapsed time. Then watch the check engine light, which remains "on", to see it began to flash, pause, flash, etc. Count the number of flashes before each pause. Then repeat the process to be sure of an accurate set of flash counts. Group the counts in pairs to form the two-digit fault codes. The last code is always 55 which means end of code readout.
Do you hear the fuel pump run for about a second when you turn the key to run. That is normal.
When you start cranking the fuel pump will start again if there is signal to the PCM that the engine is turning over that comes from the rotational sensors of the engine. If a sensor like that is bad, then that can cause the auto-shutdown relay to "open". That would be evident if you got a code 11 or a code 54 which are the fault codes for the crank and cam sensors, respectively.
If you aren't getting spark, then that too could mean the sensors are not producing reliable signals and that also causes the power to the spark coil to be disconnected by disconnecting the asd relay.
If you only get a 55 code, then I would check the egr valve which if it gets stuck ajar will cause a too lean mixture to allow the engine to start and to sustain an idle. You can lubricate the valve stem with WD-40 where it enters the body of the valve, then move the stem back and forth to loosen up the action. The internal spring should cause the valve to close to a dead stop.
Let me know the codes you get and whether the egr was remediated.
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QUESTION: This truck has had some jack-legged mechanic work done on it. The tumbler is not in the switch, therefore I have to start it with a screwdriver and toggle switch. However,I have been able to crank it up to this point without any problems. When I tried to access the codes as you instructed I'm not even getting the check engine light to come on at all. Therefore I can't get any codes to come up. I'm going to hook it up to another battery as if to jump it off because the battery is dead at this point. Any suggestions?
I would check out the egr valve based on the history of a sudden no start.
Verify that you hear the fuel pump run as I described.
See if you are getting spark by putting a plug in one of spark plug caps and touching the threads of the plug to the cylinder head while a helper turns on the starting action.
If there are no warning lights on the cluster then there may be an issue with power to the cluster or to the pcm, or possibly one section of the ignition switch has gone bad. Did you have a working check engine light before this happened?