Another update… Got the car to another mechanic… In 6 minutes (while hot) he had the engine cover, coil, and plug out of the car and was sticking an endoscope into the cylinder… Head gasket is leaking oil from multiple spots around the cylinder wall (unless it pools around the edge and appears to come from multiple spots?)
He quoted me what seems to be a reasonable / competitive price (~$2100); pending what other damage he may find inside (like… Why is my head gasket leaking at 76k miles???)
Any thoughts or ideas of what we might find? Fyi (again) I’m unaware of any overheats, but I did run the oil almost dry a few weeks ago, needed about 3qts to be full … But that was likely due to this excess oil consumption so the problem was there before the oil ran dry. Maybe the running dry just exacerbated the problems and made it worse (causing the loss of compression?)
Also, I don’t think I’m leaking/ mixing any coolant, just the oil; and appears to only be in cylinder 4, other 3 seem ok (well, they hold pressure anyway, well see what they look like when the engine comes apart).
Valves were in the open position so we could easily see into them, but couldn’t see how they seat when shut (would need to turn the can shaft for that).
I seem to remember Honda recommending changing the running chain ~100k? (I’m getting close) is it worth changing it or??? I always thought timing chains last much longer than that. Or maybe just replace the tensioner and/or guides? I don’t plan on opening this for a long time, but I do expect it to keep working throughout this long time! Any other recommended services to do while it’s opened up?
I just got through this with my '13 Accord… Note I am not sure but your year car might have a recall or extended warranty to cover certain issues that might cause this issue, find that out first!
The flashing service engine light is called “limp mode” and basically is letting you drive the car to a safe place but not making it nice to drive any further, as the problem can cause more problems if you keep driving (more below).
The primary reason for this is an engine misfire. You can get a code reader and see what engine codes come up, but they will basically point you to which cylinder(s) are misfiring, and they might also point to a coil problem (ie the coils above each spark plug).
The other warning lights are likely being triggered from this problem, and once you fix them main problem is the middle. Your other new issues will disappear once the car is running right again.
A misfire can be caused by any of the following possible problems (and the following causes of said problems:
no spark (spark plug, coil, or unlikely but possibly a bad wire in the harness that connects the coil to the ECU);
No fuel (fuel injectors, fuel pump, fuel filter)
No compression (leak in cylinder from valves, head gasket, cylinder wall damage, etc).
My car started “drinking” oil (burning) about a week or so before I went into limp mode. I didn’t see the oil but it wasn’t leaking out anywhere, just disappeared. My problem ended up being a very slight seal problem in cylinder #4 that was letting oil into the cylinder and pressure/ combustion out. I found a mechanic that diagnosed it quick and for free (I already did allot of pre-diagnosis myself and from another mechanic that decided not to take the job because he didn’t want to open the engine!) Using an endoscope camera that he stuck into the cylinder through the spark plug hole- you could literally see the oil dripping down the cylinder wall! He charged me $2100 to get me back on the road. He also threw in a timing chain tensioner for free… But I think I got a slightly good deal, if you have head gasket or valve damage then plan on spending somewhere between 2000-3000 for the repair!.
If you have a 4 cylinder car, you can easily remove the spark plugs (6cyl will probably be hard to reach the 2nd bank of 3). You can buy a Bluetooth code reader for under $20 and use torque lite (or similar) free app on Android to see/clear codes. (iPhones didn’t used to work with the bt adapter, you would need a wifi adapter unless they changed it) After seeing which cylinder(s) have problems, swap coils between bad cylinder and a good cylinder to rule out that possibility, and you can also try swapping spark plugs (or just buy new ones- the “right” ones run about $30each).
If a coil, it’ll probably cost you about 120 give or take for a new one and depending on the cylinder (6) is super easy to put a new one in yourself.
Otherwise it’ll be much harder / costlier to fix; compression test will help diagnose it but you want a mechanic with the endoscope camera or they won’t know anything until they open the engine which is an hours long job!
Oh one more thing- driving in limo mode is putting unburned fuel and possibly oil through your exhaust which will eventually kill the catalytic converter, and that is a super expensive replacement if you and up needing to replace that, too! Good luck!