Rough idle/misfire problems

[firejackal]

First off I already have checked the forums and they are not as specific as the misfire issues I'm having, and they never seem to get solved (at least updated with results) so I'm posting this here as a refresh and hope someone had this issue fixed and can help me out.

I have a '99 Civic SI ... stock engine/head as far as I know.
I've had misfire issues in the past with this car, haven't owned it for that long, starting to think I bought a bad car ... but before I had misfire issues to the fact you could feel it, so read about the car having a weak ignition coil I went and bought a MSD ignition cap, rotor, and external coil ... after those changes the car was fine for a few months then it came back, bought new spark plugs and spark plug wires, problem went away again. Now it's back again and with a vengeance, this time it's a lot different.

Here are the current symptoms that started as of three weeks ago: rough idle, while idling the CEL will flash, the code reader device says its a misfire, and each time checked and cleared its in a different cylinder.
I cannot feel a misfire, but I can feel the rough idle. But the CEL will only flash after the car has warmed up when idling, during this time the RPMs will stay around 800, it will sometimes drop and raise a little bit. Turning on/off headlights will cause the RPMs to drop a bit before going back up, almost to the point of it stalling out (the car starts to shake when the RPMs get too low during this time)

The fuel filter has been changed, and it has pressure going through it.
The spark plug wires have been checked one by one, and keep checking them just in case, I forget which brand I bought but they are much thicker compared to the previous ones in the car.

Because there is a spark I'm to the conclusion that this isn't an ignition problem. I even bought a ignition module a few days ago and replaced it today and it made no difference.
Today also the car wouldn't start, it was acting like it was flooding, had to give it gas while turning on the car to get it to start. Also today cleaned out the throttle body, no luck.

So I'm at a dead end, I'm trying to do everything I can before taking it to an mechanic (don't trust the local or big business ones around here), so does anyone have any clue? I've read posts on here talking about cleaning out the valves, which have been done, or checking the spark plugs, which are still new. Any help is appreciated, and I will keep this post up to date if anything happens.

UPDATE:
After changing the distributor the problem has been fixed.

UPDATE 2 (2011/3/4):
Everything is back, refer to my post at the end of this thread to see.

 

[Sifreak23]

You distributer is probably bad. CKP sensor is built into there and it could be faulty. how many miles on the car? d16y8 engine correct? should be for that year...

 

[firejackal]

@Sifreak23:
Thanks for the reply, researching the CKP sensor comes up with "Crankshaft Position Sensor" I don't know if this is the same thing your talking about but it looks like I can replace it if it's bad and there are instructions how to. So I'll look into that, thanks for mentioning it. If it doesn't work then I'll replace the actual distributor, but that's a bit too expensive right now.

Also since it's the SI model of the car the engine is the B16A2. The car right now has 116k miles on it. I bought it at 112k miles if the dude wasn't lying about it. But I wonder because I've found the engine mounts bad, had to replace them, and now as of last week I found that the wheel control arm bushings are cracked. This is my daily car at the moment so I don't plan on abusing it.

 

[jessye08]

had similar problem in my wifes car swapped injectors out and it ran great and that sensor could cause that also you should be able to test it. but the sensor in the distrubuter is the camshaft position sensor atleast im pretty sure it is but it could also cause that problem. any other codes than the missfire?

 

[firejackal]

Alright update on this, first off the Crankshaft Position Sensor is not on the distributor, it is on the bottom next to the timing belt.

Did a test on the sensors on the distributor and the CYP (cylinder position) sensor is reading as bad, it has a reading of around 390 when the sensor is cold, but after heating up then it reads as opened.
So went and ordered a rebuilt distributor and I will keep this forum updated with results after getting the part, too bad I can't find just the sensor and rebuild the distributor myself.

 

[Sifreak23]

Hey bro sorry about the mix up on car, when i cheked on techline for honda i was thinking you had a 99 ex, my bad. The CKP is in the distributer though, it sits on the left side when you take cap off, couldnt tell you what color it would be but its in there. CKF (crankshaft speed flucuation) sensor is the one that sits in the timing cover. Hope the rebuild distributer works man

 

[firejackal]

Installed the rebuilt distributor today and it seems to fix the problem, so that's good. I should update this thread now. Thanks for the help Sifreak23.

 

[Sifreak23]

hey not a prob bro good luck!

 

[firejackal]

well I hate to say this but now there is more problems, the new distributor fixed that certain issue but now its introduced something else.
after letting the engine heat up the car will start to run really bad, the rpms go up and down, it is hard to accelerate, releasing the gas paddle will cause the car to really slow down. a new cel is being raised "P0511: Idle Air Control (IAC) Valve Circuit Malfunction" but the IAC has been checked and it's fine. I'm honestly really done with this thing, I'm about to take it to a local honda dealer to have them look at it but I really don't have that much cash (college student) and I'm almost to the point I don't want to see another civic lol.

 

[Sifreak23]

What did you or other person check for on the IACV?

 

[jdmEK433]

I had a similar problem with my old 2001 Honda Prelude (different engine i know). Does your idle bounce up and down between 1k and 1500rpm? Also, are you throwing any random misfire codes? I had bouncing idle and random misfires in all cylinders, and no matter what I did nothing would fix it (I even put a whole new engine in)... If a code is being thrown for your IACV like you said, just pull it off and clean it out with some carb cleaner and see if that works. If it looks really dirty and clogged, then that could be causing your rough idle. This is just a cheap and simple suggestion, might not fix your problem, but who knows.

 

[firejackal]

jdmEK433: yeah the idle does bounce up and down, it use to fire random misfire codes a while ago but it is no longer, and the iacv has been cleaned several times now.

 

[RonJ]

1) Get rid of the external coil and install a new OEM distributor, if you have not already done so.

2) The crank position sensor is located inside the distributor. It's the crank fluctuation sensor that is located near the crank gear behind the lower timing belt cover.

Idle problem:
3) Thoroughly clean the IACV and then bleed the cooling system.

4) If (3) does not help the idle and eliminate code P0505, check the resistance of the ECT sensor and the output voltages from the TPS sensor.

5) Ask JohnS about code P0505. He's an expert in troubleshooting this code.

 

[firejackal]

Alright so everything is back.
So here is a quick description of since last time I posted:
1) Changing distributor fixed the original rough idle/misfire problems.
2) But this made the IACV go all funky a few weeks later and produce an P0505.
3) Checked the timing and adjusted it, and then adjusted the idle to the original specs, made the P0505 problem go away.
4) After I don't know how long, maybe just a month, now the original rough idle/misfire issues come back, with two codes: P0302 and P1399.

Just a recap on what the car does ... after the car has warmed up a little bit, a drive maybe, and then sitting at idle (like at a traffic light) the car's rpm's will drop to 500rpm or below, when it stays there for a few seconds, the car's check engine light will start flashing (Real-time misfire), before this happens you can hear the misfires. they are not as bad as misfires as I've had in the past before I changed my coil, spark plugs, spark plug wires. but it's still troublesome.
it seems the longer the car is driven the more the rpm's will drop. I haven't drove the car for more then 30 minutes at a time yet so I don't know how it will fare with an hour drive.
when the car is misfiring and the bad idle the car will start shaking including the steering wheel really bad.

There seems to be a decrease in power at lower rpm's.

Also ever since I got the car I've had terrible mpg (23mpg) which when I look at other people's mpg on their civic it makes me jealous. haha.

The spark plug for the 2nd cylinder does in fact look different then the others with a dirty white-ish substance on it.

I've already said this before probably, but this daily driver is about to get kicked cause I'm getting tired of this.
For those who may not want to go back to the top of the thread, this is a 99' Civic SI, its the model that has the b16a2 engine in it. the spark plugs are ngk iridium, and the spark plug wires are ngk as well I believe.

I've done a compression test, but I've done it wrong so it needs to be redone on my next day off, which is next weekend. when I did it I didn't do the instructions correct on having gas pump fuse out and throttle down, so my readings was 50/40/50/50 so I was like wtf, before realizing "oh, did something wrong".

 

[firejackal]

Also want to note that after the IACV problem went away the engine has been getting more noisy.
Another forum was talking about how valves need adjusted every 105k miles, and since I have no previous record of what's been done to the car I have no idea. the car has 118k miles on it now, I bought it at 112k.
the car was bought back in last august I believe, the spark plugs was changed shortly after, the spark plug wires changed maybe around december.

 

[firejackal]

from the first two weeks this has been going on it's been cylinder 2 misfiring (P0302) with sometimes a random misfire code happening (P1399) but now this week now every cylinder is misfiring while idling. It only happens after the engine heats up (usually like 10 minutes), when giving it gas you can hear it sputter. also a note, when it was doing this, the idle was dropping a lot... so last night I reset the computer, and after doing that the idle is keeping at the right rpms but still is misfiring so it is making me wonder again if it is ecu related, if I had the money to replace it or go odb1 I would.

 

[firejackal]

alright an update on this, did a proper compression test (took out fuel pump fuse, applied throttle) on each cylinder and the results is horrible. First all, the psi is horrible: 60/35/60/60 ... very bad for a car that is suppose to be around 210. so someone must of rebuilt the b16a2 engine with low compression pistons because the car is still able to run... next the cylinder 2 piston is shot, its not in good shape, rings are bad and the actual piston has rough grooves on it with some kind of white substance on it that looks like its eating away at it (you can tell how familiar I am with cars right? haha) so it doesn't look to be an ecu problem like I originally thought, I'm a computer/electronics guy, not a mechanic.