My 94 honda civic ex w/ 1.6L sohc won't start. I left it at home depot for eight hours while I went to work(car pull) when I got back it wouldn't start so I towed it home and it sat for 2 weeks. I just started looking at it this weekend.( wife and 2 kids ya know) It gets fuel but little spark. When the key is turned I get spark once when you turn the key and it cranks with no spark then when I let go of the key it gets spark and stays on very dim then dims out. I have a spark test light. I have changed Cap, Rotor, Wires, Plugs, and the Distributor twice just in case the rebuilt distr. was bad. I swapped the ECU with my buddies still same. I swapped the Main Electric Relay still same. If anyone has any idea what this could be please let me know here or e-mail me at breakdn@comcast.net

 

I am having difficulty understanding exactly what you describing above. Please clarify.

Have you replaced either the coil or igniter unit in the distributor?

Have you checked whether the ground wire connected to the thermostat housing is loose?

 

Could be the key switch cutting power to the ignition in the "start" position. Try turning the switch "on" then roll start the car or jump the starter under the hood (unplug the little wire from the starter, jump from the little wire terminal to the battery (+). Be very careful the car is not in gear and the brake set so it can't move.) If that works then find out why the ignition doesn't get power in the start position on the key.

 

I have checked all grounds their good. I changed the distributor. It has everything internally (coil, igniter pick-up, ect...) I tried jumping the started in the on position still the same. All great ideas that I didn't even think about. At least that narrowed some stuff down that it isn't. I work doubles the next 2 days but when I get off on Thursday I'm going to try a crank position sensor. Thats the only thing left that could mess with spark that I know of. If there are any other ideas I would definitly appreciate it.

 

Explaination:
It gets spark oncewhen Iturn the key to the run positionthen I let it crank for a little while and getno spark at all while cranking then when I let the key go from run to on position it sparks again and stays lit for a few seconds then dims out. I hope that explains it a little better. Sorry about that RONJ. I can picture what it is doing better than I can type it. Thanks for helping.

 

All the position/timing sensors for a '94 are inside the distributor. There is no sensor on the crank. Three sensors in the dizzy feed pulses to the ECU. The ECU generates a pulse at the proper time based on those readings which drives the igniter (ICM) module to fire the coil. That's basically the whole system as far as making sparks.

I'd check the overall timing next. Sometimes the timing belt will slip and it's a no-start even though there are sparks. Pull the upper timing cover (will need to loosen the valve cover) and set the engine to TDC1 and see if the marks on the cam pulley are lined up. You should also take each plug wire off (one at a time) and put a spare plug in it and test with actual sparks, I don't know about those light things. Also make sure you have battery voltage on the distributor wire that goes to the coil inside, all the time the key is on or cranking.

Could also be a fuel or main relay problem. Do you hear the fuel pump prime for 2 seconds when you turn the key on but don't crank? The check engine light should come on during this priming interval and then go out. If it does that put a jumper in the test connector and see if any codes blink out. If there is no code, with the jumper in place, the check engine light will come on and stay on when you turn the key on but don't crank.

 

If that's really what it does it sounds almost like it could be one of those very rare cases of a dead ECU. But it's almost always something besides the ECU itself.

Edit: But I see you've already swapped it with one from a very generous friend who would risk breaking his car to fix yours.

Most likely something just isn't getting power.

 

My apologies, but I don't understand how you are checking for spark.

Try this:

Disconnect a plug wire from a plug and insert a good plug into the free end of the wire. Ground the threads of this plug on a convenient metal engine part. Have a buddy crank the engine. You should see bright spark at the tip of the plug. Repeat for all four plugs.

If you don't see spark for any plugs, then first test whether the distributor gets battery voltage when the ignition key is turned to ON. Also check whether the timing belt has broken.

If you detect spark, check whether the timing belt has slipped a few teeth.

How do you know it gets fuel?

 

Let me respond to these very helpful ideas. First the test light I use for checking spark shows exactly what I'm getting. If I do it caveman style I do not see any spark at all. I grounded it to the ground wire up front, the valve cover, the battery, and I checked at nightjust to be sure I wasn't working all day and too tired to see straight. Then I pulled my Snap-on sparktest light out my box and tryed it and only got the spark I've posted earlier. It's getting fuel I popped off the banjo bolt on the filter andlet it blow some fuel in the engine compartment (by accident). I swapped out the main electricrelay still same.The timing belt was checked also TDC everything lines up perfect. I'm getting code 4 which is a crank position senser. I put 2 new distributors on this car and tryied my buddies just to be sure I know it has a cam position senser in the disrtibutor. ButI got this car usedand the engine block numbers are ground down on the front so this could possibly be aswap still 1.6 sohc from a previous owner. So It might be a newer motor maybe with a crank position senser(maybe a 1996 or newer lower end and 1994 head. I need to look at this a little closer and some morevoltage tests butIcan't look at it till Thursday. Thanks for all your guys help. I appreciate everything you guys are thinking of but I know its to diagnose a car without even seeing it. Thanks.

 

Yeah, focus on the code 4 and the potential block and head incompatibility issue. They may lead you to the solution. If no incompatibility exists, then carefully troubleshoot the circuitry of the CRANK sensor.

By the way, I like your label of the primitive yet effective spark test as caveman style.