Vehicle : 1997 Honda Civic LX, Manual

I was driving on the highway and notice the vehicle started to misfire or what feels like that. When I am starting to move from 1st gear I have to get the rpms up to around 3500 RPM to get the car to move off smoothly. It misfires at all gears except when on the highway in 5 th gear cruising above 55 MPH.

What I have done so far.

While the car is idling I pulled each spark plug wire separately and noticed the engine idle changes to a very rough state. So each spark plug is firing. I got 1 new spark plug and a new set of wires. I replaced each cylinder with the same new wire and spark plug. As in I did not replace them all. I just use the same new plug and new wire in each cylinder to see if it runs any differently for each cylinder with a new wire and plug while leaving all the others old parts. Nothing has changed.I then remove the throttle body and removed the MAS sensor, and the idle air control valve. I cleaned out all the carbon build up and checked the idle air control valve with a 9V battery it does operate the passage by closing and opening it.

I removed the fuel rail and turn the car on the see if there was fuel being pushed out of the fuel injectors and fuel is exiting all four. I did not check the fuel pressure since I do not have a fuel pressure tool. I checked the OHM on each fuel injector and receive 12.5 OHM on each 4.

I removed the distributor and the rotor and cap look fine. I do confess I could use a little image on what is bad or good each part. There if no oil leaking into the distributor.

I cleaned out the area where each fuel injectors sits as they were carboned up. There was no oil leak in the chamber of each spark plug.

I did a vacuum leak test by spraying brake parts cleaner and found no change in the idle rpms so no leaks.

I am a little stuck and could use some guidance. I have a check engine light on that is for the failing speed sensor p0500 or something like that and this is not related to the erratic bucking, none smooth acceleration. The speed sensor does function and the failure is with the display gauge.

Thanks

 

Automatically I would think the ignitor/icm is going bad. Try testing it and if it's bad, you could use nearly any b or d series one. Most are interchangeable.

 

How do I test this component?

 

It's probably not the easiest to test, since your car still runs. If you could get to a wrecker and rob another distributors ignitor would be the easiest thing to do. Could grab one from almost any d series or b series dizzy and put it in your and go for a drive. Would be very cheap or even free. I would never buy a new one because they are a rip off. On need a Phillips screwdriver to get it out.

 

I just got one from the junk yard from a 1997 Honda Accord. it does not fit. I did do an OHM test and find an internal open circuit. Going to get a new one to see if it has the same values or not. Why new because there are no older Civics in the junkyard and this is strange. It cost $10 USD not much for the part.

 

That's pretty cheap, someone mentioned recently about a new one being $100.. what motor was in the accord you got that one from? I have had many distributors from d15's, d16's and b16's, b18's, b20' obdo-obd2 distributors and have all similar ignitor that all interchanged. Remember, I am just the internet talking and hoping to lead to resolving your issue. I hope any of this helps you out.

 

I replaced the entire distributor and the car runs 40% better. I need to check the exhaust to see if it is clogged, and timing today. It that fails then it is compression test. The issues remain.

 

Sorry for the confusion I had a failed attempt at replacing the ignition modules as i thought they were the same in the Accord as the Civic. This is what I noticed, When I first start the car and drive off everything runs fine it is about 45 second into it that that the bucking starts. The bottom module is from my 1997 Honda Civic and the top is from the 1997 Honda Accord wagon.

The bottom ignition module is for my 1997 Honda Civic the top is from a 1997 Honda Accord wagon.

 

] SOLVED SOLUTION [
Today I finally received the following check engine code P0108 "Manifold Absolute Pressure" senor had failed. All is fine after installing the new sensor along with clearing the code. If this code had triggered before this would have saved me time and money. Hope this helps.

Thanks

 

Glad to hear! Sure is helpful info, nice to learn solutions or get helpful hints to resolve these odd problems as they come along 🍻

 

It sure was odd and the failure's symptoms are so similar to many others. Glad I did not chase the timing belt skipping a tooth or the clogged exhaust route.