Honda crx can you have spark with a bad ECU?

TxGreaseMonkey

No.

TxGreaseMonkey

Do you need any help?

dj16bit

Hey there,
Thanks for your reply. I am not sure if I have a bad ECU or two Bad ECU's or not getting proper power to the ecu.

When I purchased the car it would not t start, fuel issue . I unpluged the harness and there was no power going to the fuel pump so I ran power to the fuel pump and I was able to start the car. I noticed that the fuel gauge was not working so I asumed that the extra two cables in the fuel pump hardness had something to do with the fuel gauge. I touched the wrong cables while the car was running and it sparked and the car turned off.
Car is not getting spark now. No ignition spark After disconecting the battery terminal for 30 seconds and turning the ignition on, I replaced the main relay with a used one and tryed a different ecu,same thing no spark no blinks on the ECU. I checked all fuses, still no ignition spark after disconecting the battery terminal for 30 seconds and turning the ignition on, I replaced the main relay and tryed a different ecu,same thing.
I checked all fuses.
I am thinking that I may still need an ECU?

Thanks,
16bit

TxGreaseMonkey

Answer these 3 basic diagnostic questions for me:

1. When you turn the ignition switch to ON (not START), does the Check Engine Light (CEL) come on and then go off after 2 seconds?

2. When the CEL goes out, do you hear (or feel) the main relay "click"?

3. During the 2 second interval that the CEL is on, do you hear the fuel pump in the gas tank run?

Your answer to each question above:

1.

2.

3.

dj16bit

Answer these 3 basic diagnostic questions for me:

1. When you turn the ignition switch to ON (not START), does the Check Engine Light (CEL) come on and then go off after 2 seconds?

2. When the CEL goes out, do you hear (or feel) the main relay "click"?

3. During the 2 second interval that the CEL is on, do you hear the fuel pump in the gas tank run?

Your answer to each question above:

1.There is an orange light that I belive is the check engine light, Its a [symbol] and it doesnt turn off.

2.The main relay never clicks,I have two used relays neither one clicks. The fuel pump turns on because I temporary rewired it.

3.N/A
__________________

The car did run with the original main relay just the fuel wasn't getting 12v and that's when I ran a 12v cable to the fuel pump and it started. I then noticed that my fuel gauge wasnt working and I taped the two wrong cables at the fuel harness. Does the main relay
power the ecu in any way?
Thanks again for the help
16bit

TxGreaseMonkey

Yes, the main relay provides power to the ECU, fuel pump, and fuel injectors. The Check Engine Light staying on says there's a problem with the main relay, ECU, or ignition switch. Most Hondas will not run, if the CEL stays on. The ECU is signaling the CEL that the system doesn't check out.

First, check all under-dash and under-hood fuses with a test light or multimeter. Pay particular attention to the ACG (S) fuse in the under-dash fuse/relay box. It's a 15 A fuse controlling power to the main relay. It may be Fuse #24, but should be identified on the fuse box cover. Second, turn the ignition ON and verify you have approx. 12.5 v going to main relay connector Terminal 5. Third, replace the main relay with a new one. Fourth, decide whether you need to change the wiring to the fuel pump, turn the ignition ON and see if the CEL comes on for 2 seconds and then goes off. Also, listen to see if the fuel pump runs during this 2 second period. Fifth, if everything checks out, try and start the car.

badpenny

I might have the simple solution to your problem. I found this out with my 87 Si. There are 4 different distributor caps for these cars. And depending on where you purchase your distributor cap, you could have the one that the screw holes are not lined up properly, (adversely causing your wiring to the plugs to be off)

Razi3L

[quote=txgreasemonkey]Answer these 3 basic diagnostic questions for me:

1. When you turn the ignition switch to ON (not START), does the Check Engine Light (CEL) come on and then go off after 2 seconds?

2. When the CEL goes out, do you hear (or feel) the main relay "click"?

3. During the 2 second interval that the CEL is on, do you hear the fuel pump in the gas tank run?

Your answer to each question above:

1. No

2. No

3. No

TxGreaseMonkey

Razi3L, does your CEL stay on all the time? If it does, check your under-dash and under-hood fuses with a multimeter; then, run the K-Test on your ECM.

Read this:

http://www.askmehelpdesk.com/cars-tr...tml#post219451