Rep Power: 0

I had posted a few months back about an issue with our '04 Civic. It was running rough. I pulled the plugs and immediately replaced them all, as they were Bosch Platinums. The #2 plug had a shattered insulator, and of course, we have no idea where those pieces have gone, or what they could have done to the cylinder.

At the time, I did a compression check and we were at 145 psi on #2, and 210 psi on the other three. Once I replaced the plug, the engine ran smoothly again.

On the way to the airport two weeks ago, the engine started running rough again. I figured it might have been another coil, but no. The car was towed home, and is now parked in the driveway. Because I was not home (I drove across the country, and my better half flew out there for a week), I had our neighbor's son stop by to take a look. He did a compression check and #2 is now down to 20 psi, and he noticed that the plug was fouled with oil. When the engine is run for a bit, there is a black discharge on the driveway.

Even if we get a used engine, labor is $900-ish (about 9-10 hours of work). So that's at least $1500 total, with no guarantee the used engine is any good. The car is only worth $2000. We are pretty much ready to just replace the Civic at this point.

But I wonder...what would cause a near total loss of compression, and oil in the cylinder? A valve failure? The oil in the cylinder has me stumped though. A bad valve seal, perhaps? I don't know what condition the cylinder wall is in--it could be lightly scored from the shattered spark plug insulator, but that would not be causing the sudden compression loss. I can get a scope to look inside the cylinder if I need to.

If I don't sell it as a mechanic's special with the bad engine, I am tempted to get a used or rebuilt head cheaply enough, slap it on there myself, and sell the thing as-is, once it is running properly.

I just wonder what exactly went wrong here, and was curious to see if anyone else here had a similar failure.

I have only been home 24 hours, so I haven't had time to look at it. My '97 CR-V had been parked for a while, but it is back into service now. Those old B-series engines...just can't kill 'em, it seems.

As for Bosch...I've read about their poor quality, and to think all of this might have been caused by failure of one of their $5 spark plugs is somewhat sickening.

 
Rep Power: 518

Do a cylinder leakage test to see if it's valves or rings


The 'oil' might be soot/carbon instead of oil

Probably should have checked valve clearances the first time you discovered the compression dropped.....it may be too late to avoid a burned valve now

 
Rep Power: 0

motor swaps on those cars are pretty easy.. drop subframe and pull engine and trans together from underneath.. you can actually do it alone in about 3 hours.

 
Rep Power: 0

Yes, that could be soot rather than oil now that I think about it--it's not like my old '92 Civic that burned oil and had a blue cloud behind it (bad exhaust valve seal there).

I haven't had a chance to do any kind of leakdown test to see if it's rings or valves, but my money's on it being at least one of the valves in #2. I noticed when I ran it recently that it shakes a lot at idle, but smooths out at higher RPMs. The exhaust does make a bit of a popping sound at idle also.

I figure I'll pull the head off anyway--if it is more than the valves being burnt, then I may get an affordable used engine for it (there are a few candidates locally), and find someone to put it in. Doing that myself is beyond my patience level. If it is just the valves, I already have a line on a rebuilt head, and for about $500 I can get this thing back on the road (which would also include the timing belt/water pump/cam seal kit).

My biggest problem is going to be getting off the rusted nuts on the exhaust manifold studs. That and working outside in cloudy, damp 45 degree weather.

I would sell it as-is but we will need a spare car very soon--my daughter's transmission in her V6 Accord is acting up, and we'll need to get it repaired, rebuilt or replaced before the really cold weather hits.