byc_cb7

okay well my car wont start again. i got a new, po6 ecu, main relay, checked all my fuses, checked if there were any shorts, # 18 in the cabin is suppost to have power only when u crank the key?? i dont know what else to do. i hate electrical problems. i also checked for CEL's i dont have any.. any body else got suggestions. please let me know.

Former User

What year/engine?

Do you have spark and does the fuel pump prime?

Does the CEL work?

byc_cb7

1993 del sol d15b7 have spark fuel pump doesnt prime but i have a new relay and checked voltage to the fuel pump and its gettin power. the cel should work?

Former User

Does the CEL turn on for 2 seconds and then off after the key is turned to ON(II)?

Actually, the main relay gets power from three separate circuits. Check whether fuse 31 (hood), 24 (dash), or 18 (dash) is blown.

byc_cb7

CEL does not turn off. 18 is good 24 was blown replaced it and it does the same thing. 31 is also good.

byc_cb7

also the ECU i got is from a 92-95 civic 5 speed. its a po6. the top #'s are the same but the lower ones are diff. ill post pics later.

Former User

You have CEL code 0 when the CEL remains on steady with and without the service connector jumped. Since replacing the blown fuses, did any of them blow again? Does the fuel pump now prime? Do you still have code 0?

byc_cb7

none of my fuses have blown, fuel pump doesnt prime, and i do have code 0. whats code 0?

Former User

CEL code 0 indicates a power or ground problem with the ECU. If the three fuses are fine, start by cleaning and tightening the important ECU ground wire (G101) attached to the thermostat housing. Use sand paper to expose metal on both the ground wire and the surface where it attaches on the thermostat housing.

byc_cb7

I found the problem it was the thermo ground I had checked it before but was tight.checked again if was loose so I pulled it and sanded then tightened it back up. Worked fine after that thanks to ron u really helped me out. Damn my car was sittin for a week cuz of this damn wire. N e way thanks

1992Si

I guess you learned that lesson. I just found this thread.

That's one of the first things I learned to check. That lesson cost me $200.00 for a Pro to find it.

byc_cb7

I spent a out 100

ekallday13

hey i have somewhat of the same problem...i just bought a new main relay and it was working fine for one day but now when i turn the igniton the starter sounds like the starter starts to turn and then it slowly dies, each time after that i try to start it it turns less and less. it sounds like it wants to start but for some reason isnt. i checked my thermostat ground and sanded it so its good, just bought new main relay, no check engine light comes off and never has, but my oil light stays on and my battery light? any advice ive been tryin to fix my car for over a week and no luck!

1992Si

Dead battery.

Try jumping it.

Or have the battery tested at a auto parts store.

ekallday13

yeah i think the battery is the problem i charged it overnight and now it starts, but i never leave my lights on or anything else so what could be draining the battery? is there a way to tell if my alternator is bad?

pjschmitt

Yes, one way is to buy a meter and test the voltage across the battery when the engine is running. Another way is to disconnect the battery when the car is running. If it dies, you need to find the electrical problem. Speaking of electrical problems, there is something to try if there is ANY corrosion on your terminals. Take a can of diet coke, open it and slowly pour it on your terminals. It should eat all of the corrosion there and then you can pull the leads and clean them up a little too. DC has no sugar, so it is better than reg coke. Baking soda and a little water is the classic method for this.

DC leaves no residue and makes the car run faster because it still has caffiene in it.

You should be getting more than 12 volts on your battery when it is off or on. When the engine is running the voltage should go up and fluctuate around 13 to 14. I am sure there are more specific numbers to be provided by fellow forum members.

You can also get a little junk tester that is only for this purpose. It will light up different lights on it to tell you what the status is. I saw one that goes right on the battery leads and another that plugs into the cig lighter.

Cleaning the leads and ensuring they fit properly will take you a long way in isolating the problem. Good luck and I hope something I have written here will help you.

AllMtrRex

Hate to bring up an old thread but would specifically like RonJ's input on this.

1991 DX. Recently replaced head gasket. Car starts but idles high (no tach to be specific)

At first I was getting ecu trouble code 16 but it was not consistent. Car would start some time and some time not.

Didnt do anything, later the code 16 was gone and the car starts idles high for about 30-1min and all of a sudden check engine light glows and the ECU is throwing a code 0 while the car is still running but the idle increases I would guess to about 4000-5000 rpms and does not change.

I know the ground on the thermostat is tight but may need to be sanded. The car is completely stock (wiring, etc.) and was told from an elderly man who owned it before me, that it ran fine.

So if it is a bad ecu but still able to start and run that would be the first for me. No other codes but code 0 as of right now. Any suggestions would help.

thanks

Former User

Code 0 is when the CEL remains on steady but the LED on the ECU does not blink any codes. Is this true in your case? Given that the engine still runs, there may be a short in the Grn/Orn wire running between the ECU and cluster or the ECU is bad.

The high idle is probably a separate problem.

AllMtrRex

Its like this exactly. Turn key over, fuel pump primes, main rely clicks check engine light flashes like usual then goes off. The Car starts and then runs. Takes gas fine. But 30 sec to 1 min later the check engine light comes on and the ecu light stays solid (while jumped with a wire to inspect codes) As soon as the check engine light comes on is when the engine revs and no matter what will not return to idle. I will try another ecu but in 10 years of troubleshooting these cars I have yet to have a bad ecu but able to start and run the car.

let me know if you have any questions or anything you would like me to try.

Former User

So I guess your 91 DX is converted to OBDI. When the CEL turns on while driving, do you turn the engine off and then jump the service connector? If so, next time the CEL turns on while driving, pull over, leave the engine running, and then pull the code. You may then get a code to blink from the CEL.

AllMtrRex

No the Car is still Obd0. I had it jumped previously from pulling a code 16. I left it in there and returned and started the car forgetting it was still jumped. Started the Car and was surprised by no immediate check engine light. Checked for leaks and etc while the car was running. All of a sudden the idle changes to a high rev while standing in front of the car. I looked into the cabin of the car to read if it were over heating or throwing a code. I seen a solid lit check engine light. Looked over at the ecu and it was solid lit and then noticed the jumper was still jumped.

Former User

What exactly did you jump? To retrieve codes from an OBD0 ECU, you just turn the key, right?

AllMtrRex

hmm. i was jumping a blue plug hanging down on the passenger side kick panel lol. I haven't owned a obd0 car with check engine problems in years. I'll kick myself if the blue jumper is useless. But still does not help my problem jumped or not because after a minute running I am getting a constant check engine on the dashboard. The light is not faulty because it displayed a code 16 before this code 0. Now you got me googleling lol

Former User

Start by unjumping the blue plug. I don't know what effect this may be having.

When the CEL turns on while driving, have you ever pulled over and, with the engine still running, checked whether the ECU LED is blinking a code?

AllMtrRex

actually the cel comes on 30 seconds after start up so Im not driving however, the engine is running. And with the engine running with the check engine light on like stated above and the high rev neither the check engine light on the dashboard or ecu (red light in ecu window) blink. They both stay lit but only 30 seconds after start up. There are no check engine lights when before the car starts in "ON" or after running for a short period.