need some input on coil pack problems

[Streetracer0442]

okay i have posted the problems i have been having, got alot of help from everyone, now i have one last problem to fix and my car should run again, hopefully. okay i was having fuel problems, turns out the pump wires were hooked up backwards. newbie mistake on my part. after switching those around i know have near perfect fuel pressure. now for the electrical problem i am having. my cars been in the shop for 6mo, just got it out cause i was tired of paying for nothing to get done. and i asked the mechanic for a list of what they did, tested, etc. he didnt give me any numbers for the test but im sure i can get the voltages, resistance numbers myself if need be. okay the problem i have no ground to half my coil pack, when i tried to check the voltage for each post, i got the recomended voltage for 2 and 4 but 1 and 3 read 0 which is confusing me cause i thought 1 and 4 were working together and 2 and 3 worked together. heres what the mechanic wrote on the report he gave me "still no spark from coil, tested coil wiring, tested ground signal from pcm to coil. no ground to 1/2 the coil. tested wiring between coil and pcm. no problems found, tested power and ground circuits to pcm, no problems found. removed timing covers and inspected timing marks, no problems found. suggest replacing Pcm and retesting." okay i just bought a remanufactured ecu b4 putting the car in the shop. so it has to be good, unless i have that horrible of luck. im gonna change the crank sensor 2 morrow afternoon and see if that fixes anything. also the relays i have changed, spark plug wires and new plugs, put on a new coil pack and same problem from the same 2 towers 1, and 3. sorry so long just tryin to give u all the info i have. car is a 95 gs, full cat back exaust and cold air intake, those are my only mods.

also if anyone can tell me how to match up and ecu from a neon, to my eclipse for testing the ecu that be great. i tried Vfaq but didnt find much help there, i know it has somethin to do with the vin numbers or numbers on the ecu i just dont know which.

 

[eclipsers-t]

WOW! I am not sure what you are asking. The paragraph all seem so to run together. Please type out questions individually.

-Andrew

 

[4UH8ERS]

Good idea that sounds exactly like the crank sensor. Change it and let us know.

 

[dr1665]

The ECU needs to see proper signals from both the cam and crank position sensors (CMP and CAS, respectively) or it will activate the auto shut down (ASD) relay located on the firewall next to the fuel pump relay. Before you go spending money on replacement sensors, take your multi-meter* and back probe each of these sensors. You can do this at the sensor connections themselves or where they terminate at the ECU.

*A good multi-meter is a MUST HAVE for ANY tuner. You can find a quality digital CRAFTSMAN model in the $25 range at Sears. Mine is nearly five years old and has only needed the batteries replaced once. It's served me well over time. Like I said, MUST HAVE.

To back probe a sensor/connection, you stick a pin/paperclip into the backside of the connector where the wire from the harness goes in. Then you either touch your meter leads to these pins to do the test or clip alligator clips to the leads and pins to give you free hands during the test.

For both the CMP and CAS, you will be looking for an alternating 5VDC during cranking. Be sure to disable the fuel pump while performing this test. The CMP is easier to see because the cams turn at 1/2 crank speed. If you see these sensors are switching while the engine is cranked, then you know they are fine. Proceed to test the ASD relay for proper function based on information in your Chiltons.

If you're not familiar with relays, they usually have (4) terminals. When current flows from, say, pin 1 to pin 2, it closes the circuit between pins 3 and 4. They are a safety precaution to keep heavy current loads flowing through all the small guage wires in the harness of the car/ECU.

Finally, be sure to check that you are getting the proper signals at the end of the harness where it connects to the coil. If you are getting crank/cam reference, then you should get signal at the coil. If you're getting signal at the coil, it's pretty safe to assume your coil pack has shit the bed on you.

Okkam's Razor. Good luck.