90si-rex

Hey all....I'm having a problem with my 2000 Civic EX misfiring. It started last week while I was driving on the highway. I pulled the codes and had a P0304 and P1399. I changed the plugs with NGK plugs, reset the ECU, and it came back with P0300, P0302, P0304, and P1399. I changed the plug wires and it came back with P0304 again and P1399. Then I changed the cap and rotor, and air filter, and I'm still getting the P0304 and P1399. I had also read on several sites that the valve adjustment being out of spec could cause a misfire, and since I wanted to change the valve cover gasket anyway, I did a valve adjustment. A few of the valves were out of spec. A couple were really tight and some of them were loose (not sure if that's the right term) but it didn't seem to make any difference. I'm kind of at a loss as to what to look at next. In my reading, I've come across some stuff that says clean the EGR valve/ports, and other stuff that says the D16Y8 doesn't have an EGR, so that's got me a little confused. I haven't done a compression or leak down test yet, and honestly, I'm not even sure how to do either of those. What am I missing? I've come across so much conflicting information that I'm really not sure what to look at next.

I should also mention that the CEL isn't on steadily. It's blinking, which I'm assuming is worse than if it was just on steady all the time.

Former User

Compression test the cylinders.

Check whether injector 4 sprays fuel.

90si-rex

Will do. I've never done a compression test, so I'm not 100% sure how to do one. Is this something I should be able to do relatively easily on my own?

I also forgot to mention that the #4 spark plug did have a bit of oil on it when I pulled it, but not what I would call excessive.

Former User

Start with the compression test. The test is not hard, but you need to buy or rent the gauge kit.

http://www.popularmechanics.com/cars...test-14912158/

90si-rex

Awesome! Thanks. I'll have to check that this weekend when I have some time. I'll post my numbers once I do.

mk378

Take all 4 spark plugs out and leave them out while you test one cylinder at a time.

If compression is OK, swap the #4 fuel injector with #1 and see if the problem moves with it.

90si-rex

Thanks. I'll give that a try as well.

One thing I'm still confused about is the EGR. Some of the stuff I've read says the Y8 has an EGR and that it may need to be cleaned, and other stuff says it doesn't have an EGR. So does it or doesn't it? I found a video on how to clean it, but about halfway through the guy said it was a different engine (Y5 I think) so I'm not sure what he did would apply to my car. It looked easy enough, so if it does apply it's probably worth doing even if that's not my current issue, but if it doesn't apply then I don't want to waste time trying to do something that doesn't even apply to my vehicle.

Former User

No EGR system.

90si-rex

Thanks. Now I know not to waste my time trying to figure that out.

90si-rex

Just did a compression test. This may have been a little overkill, but I did each cylinder 4 times. Numbers are below:

Cyl 1 - 165, 165, 170, 175

Cyl 2 - 185, 185, 190, 180

Cyl 3 - 120, 120, 125, 125

Cyl 4 - 0, 0, 0, 0

So obviously cyl 4 is dead, and now I really don't know what to do. Any help is appreciated.

mk378

It could be a valve that is too tight. Take the valve cover off and turn the crank by hand until the cam is not pressing any of the valves on #4 (to be precise about it, TDC #4, which is 180 cam degrees from TDC1, so the "up" mark on the cam pulley should be down instead of up).

With the valves closed, grab the end of the rocker arm with your fingers and try to move it up and down. The rocker arm should be able to move up and down with a little slack, with the screw tapping on the top of the valve stem. If they don't get slack, go through the valve adjustment procedure.

Edit, #3 not looking too hot either. May be time to replace engine.

90si-rex

I did a valve adjustment last weekend and everything seemed ok. Thinking it might be time to start planning a swap...

mk378

If you have an air compressor you could do a leak-down test. But at this point simply replacing the whole engine is usually the most practical thing to do.

90si-rex

I may be able to get a cylinder head from a guy I know. Would it be worth it to just replace the head and call it a day?

eghatch9295

iTrader: (1)

possibly, it is rare to see a cylinder throw zero compression from only bottom end problems. try a wet compression test on that cylinder.

90si-rex

I think I'm done with all the testing I'm going to do. The hunt for a replacement begins.

On a side note, if you know anyone in the Maryland/Delaware/DC/Southern Pennsylvania area selling a D16Y8 please let me know.