UPDATE*****

Ok I did the compression test,

Cold engine
4- 178
3-174
2-145
1-175
Engine after warming up for 10 min

4-175
3-170
2-125
1-177

Hey fellas, I'm new to this forum but I'm a half decent mechanic. Owned a few Hondas and have worked on them on occasion. Well I just recently bought my daughter a 2000 civic DX, it ran fine for a few weeks, now I'm getting misfire cylinder 2
I changed plugs to ngk. (correct gap)
New wires
New cap
New rotor
New number 2 injector.

Started the car after the plugs and idled fine for maybe 2 minutes, then engine started losing idle. I pull number 2 plug wire WHILE it's idling badly, and no change. Plug it back in, no change, same poor idle.

So I ordered a new injector for rockauto for the number 2 cylinder. Replaced the injector, fired it up, idled fine. I pulled the number 2 wire and it idled poorly. Put wire back in and it idled fine. 2 minutes later, engine starts to idle poorly and code comes up again, cylinder 2 misfire. Engine is idling poorly and there is a no change when I pull number 2 wire even after I've replaced everything I can think of. Please if anybody has any advice, I'd appreciate it.

-Charles

 

Maybe do a leakdown and compression test on the bad cylinder next?

 

Try to reset the ECU, unplug the battery or ECU fuse for a few mins and start the engine.

You might have a break in that injector wiring. Test/inspect the injector plug/ wiring and try to find the break.

 

Ok well this morning before work I unplugged the battery, came home and plugged battery back in and fired up the car. It ran fine for around 5 minutes, then started idling poorly, same issue, misfire number 2. So I even went as far as to swap the new injector to cylinder number 3, and put number 3 injector into number 2 spot. Well fired it up and still having same issue, misfire on cylinder number 2. It idles poorly and still when I pull the plug wire, I don't notice a difference in the idle speed.

Any clue on how I could test the injector pigtail? What should it read? Or is there something bigger I'm missing?

Again, it seemed to idle just fine once I plugged the battery up from being unplugged all day, then it seems like when it got up to temp, it starts acting up

 

I just finished working on an Outback with a bad cylinder 4 mis fire. Swapped everything , nothing fixed anything.
Pulled the head (don't have a leak down tester at home), Found both exhaust valves bent at cylinder 4.
I know it's a Subaru, but worth checking out with a leak down test.

 

**** I hope that's not the case, already put alot of money into it, don't want to spend a arm and a leg replacing the valves

 

But wouldn't it be idling rough from a cold start? From a cold start it seems to run fine. Granted the idle is up a tad more

 

Anything is possible, just throwing out ideas before you keep throwing parts and money at it.
Rule that out then you know you have a good engine at least.

 

As mentioned, it's past time to compression test the cylinders. For the tests, make sure you disable the fuel injectors and hold the pedal at WOT while you crank the engine for 20 seconds. Compare #2 psi to psi of the other three cylinders. Then go from there.

 

When you swapped injectors from one cylinder to the next you should of pulled the injector plug not the spark plug wire! When you pull the injector plug clip off the injector and no change is noticed there is a issue with the wiring not the injector itself! Look at the wires closely especially inside the plug! make sure the prongs are in good condition and make solid contact when plugged into the injector top. Search the manual on the resistance to check for on the injector plugs and or check for continuity there might be a break in the signal to the ECU.


It also sounds like you have a bad ECT sensor, test the ECT with a multi meter and trouble shoot the ECT sensor, If it runs good when it starts cold and as it warms up starts to idle bad and misfire it sounds like a bad ECT sensor! its easy to test!

 

Ok thanks, I'll do that, but what is a ECT sensor?

 

I have no idea why wunf has mentioned the ECT sensor. Makes no sense. Focus on the compression tests.

 

I'll try compression test tomorrow, thanks

 

OP - (ECT sensor) Engine coolant temp sensor!

muellersfan because a bad ECT sensor can cause issues when the engine reaches OP temp. So your telling me it wont??

ECT sensors can go bad and not set off a check engine light! in fact the very same thing happened on my B series last week! my ECT sensor was showing low temps when the engine warmed up fully! showing the ECU my temp was 154* when it should of been around 180* it did not set off a check engine light through Hondata but it caused my tune to run rich! After testing the ECT I confirmed the resistance to be under what the manual calls for! after swapping a new OEM ECT sensor the engine warms up to 180* and no longer runs rich.

I go by my experience and if you ask me I don't know why your telling him to do a compression test? If he already stated the engine starts and runs fine until it reaches OP temp then doing a compression test makes no sense to me at all!

 

Valve adjustment. If it is slightly too tight, it can run properly when cold, and then as the engine warms up, the valve and rocker arm material grows and pushes the valve off the seat... then the misfiring begins.

Check compression while the engine is both cold and warmed up. A difference in the compression results of the #2 cylinder would indicate a valve related issue. If so, let the engine cool down fully and do a valve adjustment.

 

Not in one cylinder.

 

You may be right,

I only threw it out there as a simple test he can do and at least rule out if he had a bad ECT sensor, it might not cause his misfire but it could also cause a rough rich condition when warmed up which could possibly be a separate issue.

Hopefully its a bad injector signal in the harness and worse case he has low comp in that cylinder and needs a rebuild.

I'm not here to argue with who's right and who's wrong! im here to help people like I have for over 10 years on this site ok, if you think you are so knowledgeable that you dismiss others advise as if you are 100% correct then you need to take a break! 2 brains are better than 1!

 

Based on reading your posts, your tech knowledge is well below average compared to other regular tech posters. Please understand that posting bad tech information in threads does much more harm than good. Helping may sometimes mean that you should not post anything in a thread.

 

LOL Sure buddy because your above average!

 

Read more, post much less. That's the best advice anyone knowledgeable about Hondas could give you.

 

lol dude I have like 50 dyno sheets of B series engines I have hand built and had tuned I can post up for you! both All motor and Supercharged setups that I assembled, I have built many Engines and sold them here on this site with success if you don't know anything about a person don't post up non sense about them like you know anything about me or what I know! I have been doing this a long time son. I have been driving Civics and Integra's a long time and been there and done that! I don't claim I'm a expert or the best, I go by my experience and I never post up anything that is not going to be helpful so again you should go take a break!

 

Bla...bla..bla

All your "so-called" experience has not prevented you from giving horrendous advice in tech threads. You don't understand how Hondas work. I've mentioned this to you previously, and I'm mentioning it to you again now. Please stop posting BS information in tech threads. If you don't, I will continue to call you out for bad advice.

Again --> Read more, post much less.

 

Sounds Familiar...

Lmao continue all you want son! cause you just sound like a hater! Lol

 

Lol man, I didn't know I would be getting advice and entertainment from this thread. Didn't get a chance to check compression yesterday cuz of work but I think I will check the valves with a feeler gauge since that is essentially free and pretty quick. I'm hoping maybe just a valve adjustment will fix my issue

 

A compression test will tell you more than the feeler gauges

Were all thinking blown head gasket so thats why we say compression test


Any check engine lights?

Engine needs air fuel and spark. You've checked 2 out of 3 so far and the best way to check air is by a simple compression test