Chrysler Repair: 93 New Yorker 3.3L V6: no start/no spark


Question
QUESTION: Ron,

I recently converted my battery terminals from side post to top post.  However, after doing so, my engine now only cranks but will not start.  On the negative terminal, there's three wires -- one large black wire to chassis ground and two smaller black wires in a harness to the starter and solenoid.  Also, I see four wires connected to the positive terminal -- a large red one to the starter, a second large black one to the PDU, and in a harness, a third smaller brown wire to the solenoid, and a fourth smaller wire (black with blue stripe which says "fuse line") which I traced to the crankshaft position sensor.  All wires have continuity when I tested them with my meter.  I've also confirmed all fuses and relays are working both in PDU and beside glove box.  I've recently installed a new fuel pump and fuel filter and both the ASD relay and fuel pump relay click when the key is turned and fuel also squirts from the valve on the fuel rail, so I know I have a "no spark" condition.

I first tried pulling a spark plug wire and touching it to ground with a screwdriver and tried to start the car but did not get any spark.  Next, I tried to start the car while using a test light and got no voltage at the electrical connector which feeds the coil pack.  I then tried replacing the crankshaft position sensor, but still have the same problem.  I don't think this would be a timing issue, so I'm now at a loss.  Any suggestions you can provide would be greatly appreciated.  RSVP, thanks!

ANSWER: Hi David,
Did you try a fault code readout using the ignition switch: "on-off-on-off-on and leave on" doing that in 5 seconds or less elapsed time? The watch the check engine light, which remains "on", to see it begin to flash, pause, flash, etc. Count the number of flashes before each pause. Then repeat to assure an accurate set of flash counts. Tell me the counts in order of appearance and we'll go from there.
The '93 Salon is the AC-body which ended it run in '93. My wiring diagram for the battery differ a bit from your description:
on the negative post the largest black wire goes to the engine, and two smaller black wires of which one goes to a splice where it supplies 4 smaller wires (2 black/red, a black/yellow and a black)  and the other to a splice to the left of the radiator which supplies 3 black wires;
on the positive post one large red wire to the starter motor, one large black wire to a disconnect and thence to the power distribution box, and one narrow black wire to a 4-pin disconnect from which a bigger black wire goes to fuse 2 in the pd box which then goes to the hazard flasher system. May someone have re-wired the battery post clamp wires?
Roland

---------- FOLLOW-UP ----------

QUESTION: That's possible.  The brown wire and the black wire with the blue stripe were previously cut and spliced back together, but have continuity to the positive terminal.  When I checked the fault codes, I'm currently getting 12, 22, 24, and 55.  Could any of these this indicate a possible re-wiring?

ANSWER: The 12 means battery disconnected recently, 22 means engine coolant temp sensor voltage too high or too low, and 24 means throttle position sensor voltage too high or too low, and 55 means end of readout. Those sensor voltage codes make me wonder if the black ground wire at the 4 wire splice on the negative post might be disconnected as it is one of the reference power ground wires for the pcm (although it also is the ground for the authshutdown relay which seems to be working. So that may not explain your no start. Again, on the positive clamp I don't see a wire that was supposed to go to the crank position sensor (as that is supposed to be powered by 8 volts from the pcm on an orange wire; nor do I see a brown wire to a "solenoid" (which one?).
When you say the fuel pump runs, when you turn the key to run, that should only be for about 1 second, unless you then start cranking it over and it catches and runs.
So this is strange. But it worked before you changed the clamps, which is surprising.

---------- FOLLOW-UP ----------

QUESTION: I'll have to re-check my connections and look for the hook-up you've described above -- in particular, the ground wires at the 4 wire splice.  It sounds like my wires may not be hooked to what I thought they were after all.  I'm hoping that I haven't fried the PCM or ECM.  The fuel pump, however, appears to be working fine since it only runs for a second when the key is turned and there's fuel in the rail.  Thanks again for the response and I'll try to do some additional troubleshooting and get back to you.

Answer
You know that you don't have spark. But you don't know if that is because there is no power to the spark coil pack or it isn't being "driven" to spark by the pcm. The fact that the fuel pump runs for a second says that the fuel pump relay and the pump work, but you need to listen/feel whether the relay clicks or the pump actually runs when you start cranking it over or not. Similarly, check the dark green/orange wire at the plug to the spark coil. It should behave the same way, although it is operated by the autoshutdown relay, along with the fuel injector powering by that same wire. Unless you have both fuel pump and spark coil and fuel injector being powered while you are cranking you will not get it started.
I would not focus on the black ground wire from the battery to the pcm unless you think it is 'open'; it should be patent to pins 5, 11 and 12 of the pcm if you want to check it out.
What has changed about the situation since it last ran in the bottom line question.