Please bear with me here as I describe the series of events. (note: DX was parked 5 years ago due to broken piston rod. CRX was driven on and off trailer and ZC motor was running good - no smoke and like a sewing machine)
1. obtained 91 CRX with ZC aftermarket to put in 91 DX Wagon
2. Bolted DX tranny on, modified wiring harness for MPFI, and put PM6 ECU from CRX in
3. ECU light blinked once as it should with ignition on, engine off.
4. Complete installation of all ancillary equipment, wiring, new fuel filter, etc.
5. Engine cranks but won't start. ECU blinks once everytime ignition on.
6. Hmmm... Fuel pump?
7. Open fuel pressure relief bolt.. sure enough no fuel.
8. Check Haynes manual on which wires go to fuel pump and find mine don't match manual (useless garbage.. should have gotten a Chilton which is usually a lot more useful with wiring and other technical info.
9. Pull fuel pump from CRX, drop DX Wagon tank and notice pumps are a little different. CRX wires match description in Haynes manual but now I see which wires I need to test (should have deduced that earlier from what could be seen under back seat).
10. No voltage on fuel pump wires.
11. Main relay? Pull known good from CRX and put in DX. Still nothing. Read up on main relay issues and testing and find I must check within 2 seconds if I am not going to crank motor. Perform full relay check since I have it out. All good.
12. It is late when I get a chance to get back to this.. quiet too (no kids talking, dogs barking, general noise). Volt meter shows 12V for 2 seconds and I do hear main relay actually activate and deactivate.
13. Add rest of wiring to harness that goes to fuel pump and check at fuel pump connector. All good.. 12V for 2 seconds. Wow, I might have this licked.
14. Reconnect fuel pump to determine if I can hear it start. No go. But wait, I did not hear relay click either. What the heck.
15. Disconnect fuel pump, recheck voltage on ignition and nothing. No voltage, no click from relay. Great!
16. Pull relay and put it through diagnostics again.. All checks out fine. I put the battery back on charger at this point while off having to do something else but did not disconnect terminal wires.
17. Remove charger and slightly more spark than usual from terminals but definitely not out of ordinary. I mention this because it could be useful in deducing what I found next.
18. Reinstalled relay, tried to see if I could get voltage on the fuel pump circuit again. Nothing. But now I notice as I am staring at the floor wondering what to do next that the ECU light is not blinking once on ignition.
I have no idea when during this whole process the ECU stopped its power on check blink but it now doesn't seem to respond. Checked ECU fuse and it is good. Was it when I reconnected fuel pump thinking it might work now or when I charged the battery?
Any suggestions as to what to do next? Is there any other check I can perform on ECU to see if it is good? Already took cover off and did visual inspection of IC board. Nothing out of ordinary.
1. obtained 91 CRX with ZC aftermarket to put in 91 DX Wagon
2. Bolted DX tranny on, modified wiring harness for MPFI, and put PM6 ECU from CRX in
3. ECU light blinked once as it should with ignition on, engine off.
4. Complete installation of all ancillary equipment, wiring, new fuel filter, etc.
5. Engine cranks but won't start. ECU blinks once everytime ignition on.
6. Hmmm... Fuel pump?
7. Open fuel pressure relief bolt.. sure enough no fuel.
8. Check Haynes manual on which wires go to fuel pump and find mine don't match manual (useless garbage.. should have gotten a Chilton which is usually a lot more useful with wiring and other technical info.
9. Pull fuel pump from CRX, drop DX Wagon tank and notice pumps are a little different. CRX wires match description in Haynes manual but now I see which wires I need to test (should have deduced that earlier from what could be seen under back seat).
10. No voltage on fuel pump wires.
11. Main relay? Pull known good from CRX and put in DX. Still nothing. Read up on main relay issues and testing and find I must check within 2 seconds if I am not going to crank motor. Perform full relay check since I have it out. All good.
12. It is late when I get a chance to get back to this.. quiet too (no kids talking, dogs barking, general noise). Volt meter shows 12V for 2 seconds and I do hear main relay actually activate and deactivate.
13. Add rest of wiring to harness that goes to fuel pump and check at fuel pump connector. All good.. 12V for 2 seconds. Wow, I might have this licked.
14. Reconnect fuel pump to determine if I can hear it start. No go. But wait, I did not hear relay click either. What the heck.
15. Disconnect fuel pump, recheck voltage on ignition and nothing. No voltage, no click from relay. Great!
16. Pull relay and put it through diagnostics again.. All checks out fine. I put the battery back on charger at this point while off having to do something else but did not disconnect terminal wires.
17. Remove charger and slightly more spark than usual from terminals but definitely not out of ordinary. I mention this because it could be useful in deducing what I found next.
18. Reinstalled relay, tried to see if I could get voltage on the fuel pump circuit again. Nothing. But now I notice as I am staring at the floor wondering what to do next that the ECU light is not blinking once on ignition.
I have no idea when during this whole process the ECU stopped its power on check blink but it now doesn't seem to respond. Checked ECU fuse and it is good. Was it when I reconnected fuel pump thinking it might work now or when I charged the battery?
Any suggestions as to what to do next? Is there any other check I can perform on ECU to see if it is good? Already took cover off and did visual inspection of IC board. Nothing out of ordinary.
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