Hello Everyone,


Recently my car started to throw CEL codes P0300, P0301, P0302, P0304, basically misfires on cylinder 1,2,4 and random multiple misfires.

To remedy the problem, bought new plugs, and coil packs for all four cylinders. The problem went away for a couple hundred miles or so.

The problem came back, at this point I figured it was the injectors. So I added some fuel cleaner (techron) and the problem seemed to go away for 200 miles or so.

The codes came back but now only for cylinders 1 and 3. At this point, I took out all the injectors and DIY cleaned them and put in new gaskets. The codes went away for a good 300 miles.

The codes came back AGIAN! I did a compression test today and the numbers that came back were: 115, 215, 225, 225, cylinder 1,2,3,4 respectively.

Lately I have been noticing much more oil consumption and a lot of soot on the exhaust pipes and rear bumper.

I am soon to do a leak down test, but judging from what I am seeing I am thinking its either the an issue with the exhaust valves, piston ring, head gasket, or any combination of those related to cylinder one. The car is an MY00 with 208K miles on it.

Should I just be prepared to get a new motor instead of spending more time on this?

Just on a side note: I recently have done a valve job on the car replacing the valve retainers, valve stem seals, and did a lash adjustment.

I am thinking maybe to recheck the lash clearances, but something is telling me this is gonna be bad news.



What do you guys think??

 

Did you ever go back and re-check the installation of the spark plugs? What torque did you use? Honda increased the torque from 14 to 18 #ft but I recall Billman says 22#ft is the way to go. He did a test to see how far he could go (on an extra block) and I think he went over 50 without any damage.

 

Start with the leakdown test and go from there.

Could be something simple enough to just fix.

 

Valve adjustment and get the injectors flow bench tested

 

These don't exist. Cylinder head perhaps. Valve job?

-- Chuck

 

Without knowing what the root of the issue is, this is irresponsible ‘advice.’

 

Huh?

-- Chuck

 

Seems to be some confusion. I think op meant get a used motor, not a brand new one ('new' meaning different). Yes, new motors don't exist.

Valve adjust do over seems like step one. Maybe something was done wrong, or an adjustment came loose, etc.

Top tip, always make sure valve you're adjusting has its cam lobe pointed up, 180 away from follower. Otherwise you messed up timing marks or counting degrees of crank turn.

In fact, just ignore timing marks and counting crank degrees, and just use 180 away method. Turn crank while watching cam lobes. When a lobe is pointed up 180 away, adjust. Repeat until all have been adjusted. Much faster and easier and way less chance of error.

 

Thanks for the replies. Yes, I meant a used good conditioned motor.

Here are my leak-down numbers: 75%, 2%, 5%, 20% on cylinders 1,2,3,4 respectively.

Coolant level didn't get affected, and didn't try the dip stick method cause my valve cover is off, and I hear some faint noise coming from the tail pipe, but I do not know it is an abnormal amount of noise.

I peeped thru the spark plug hole with a borescope cam but I am not able to get a good look at the walls because of how the camera is point straight, but from what I see looks like there is nothing abnormal or scored.

Some of the lash clearances are a bit off but not by much; would this have a big effect on a leak-down or compression test, as well as misfiring?

 

I don't think that high of leakdown can possibly just be a valve adjustment unless it has absolute zero clearance and is remaining partially open at all times. The high leakdown may actually be really good news.

Was the car misfiring before the head work was done? Why was the head work done to begin with? What parts were used? I'm assuming that they at least looked at the cylinders while the head was off? Did they check to make sure the head was flat? What kind of shop was this?

I'm betting the valve seals were installed incorrectly. I don't know head work very well and hopefully someone can point you in the right direction but given the leakdown and oil burning, it sounds like the oil and air are passing through the valve seals. I think you're going to need to take the head off no matter what and can inspect the cylinders/pistons while it's off. I'd be a bit skeptical of going back to a shop that did this work. If they have a good reputation otherwise, maybe give them a chance to fix their mistake? If it's a shop that had no business taking apart an engine to begin with, you may be better off cutting your losses and taking it elsewhere.