1998 Dodge Neon car died and will not restart -3rd posting

  • 1998 DODGE NEON
  • 4 CYL
  • FWD
  • 90,000 MILES
Have posted 2 previous questions(1-15-09 and 2-10-09) and got good diagnostic answers BUT still can't get to start. To give someone an overview: engine will try to start so ck'd fuel pressure, ok. Ck'd spark and have spark on 2 & 3 cyl, no spark at 1 & 4 cyl. Replaced coil pack, no start. Checked for pulse and no pulse for 1 & 4 cyl. Ck'd wiring for opens at coil pack to pcm, ok. Replaced pcm with rebuilt pcm from internet supplier Auto Computer Exchange, still no start. Ck'd and no spark on any cylinders. Reinstalled old computer and got spark on 2 & 3 cyl. Again. Sent back rebuilt computer for exchange. In the meantime replaced crank sensor, no start. Ck'd wires for open, ok. Installed second rebuilt computer and no start, ck'd and did have spark at 2 and 3 again nothing at 1 and 4. Reposted question and got repy that related to cam sensor. Replaced cam sensor, no start. Ck'd wires ok. Also have ck'd for codes repeately and no codes present. What to do now?
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have the same problem?
Monday, February 16th, 2009 AT 1:58 PM

1 Reply

You seem to have replaced and checked everything else. May as well check the ASD relay and wiring. Although this supplies ground to coils and you must have ground for it to fire cylinders 2 & 3? Also check the slots on outer edge of flywheel/flexplate or on crankshaft counterweight. And the slots in cam timing sprocket or check you are getting pulse from these? CKP pulse wire is grey/black the CMP pulse wire is tan/yellow

ASD relay and electric fuel pump relay are energized when ignition is on. These relays are controlled through PCM by switching a common ground circuit on and off. Following components are controlled by ASD and fuel pump relays:
Electric Fuel Pump
Fuel Injectors
Generator Field Winding
Ignition Coil(s)
HO2S Heating Element
When ignition switch is turned to RUN position, PCM energizes ASD relay and electric fuel pump relay which powers these components. If PCM does not receive a CMP and CKP sensor signal within one second of engine cranking (start-up), PCM will turn ground circuit off and de-energize ASD relay.

On Distributorless Ignition System (DIS), CMP sensor reads slots in cam timing sprocket. PCM uses this information along with information from Crankshaft Position (CKP) sensor to determine if fuel injectors and ignition coils are properly sequenced for correct cylinders.

CKP is a Hall Effect-type sensor. On some vehicles, CKP sensor is mounted on left rear side of transmission bell housing. On other vehicles, CKP sensor is mounted on right rear side of block, near cylinder head. Sensor reads slots on outer edge of flywheel/flexplate or on crankshaft counterweight. Each slot causes a pulse to be generated as it passes under CKP sensor. Signal generated provides engine speed and CKP information to PCM, which along with other input signals, determines fuel injection sequence, ignition signal and spark timing.
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Monday, February 16th, 2009 AT 7:41 PM

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