Hello all,

I have a 2005 AP2, with 71k miles on it.

Recently a CEL started popping up so I took it to my mechanic. These are his notes:

NOTE: Valve adjustment was done ~2 years ago at ~60k miles

My mechanic wants to go all the way to dismantling the engine in order to see if it will require rebuilding because he cant' find out what exactly is wrong. Does this seem reasonable?

Thanks for any responses.

 

Maybe do a cylinder leakdown test?

 

Tearing it down is unreasonable. Do not allow him to do that! Have him test your injectors. Cylinder 2's injector might be sticking and about to stay stuck either open or closed.

 

I can ask him to do a cylinder leakdown test and to test the injectors.

Do you guys find it likely that my valve adjustment was done poorly? I had no check engine light come up for at least a year after it was done. Would it make it sense for an issue with that to rear its head later?

 

Do you have access to another set of coil packs that you know are good? If so ,swap them first and see if the issue persists. I know it sounds crazy, but people having multiple, or all coil packs failing close together is not all that uncommon. Your mileage is a bit low for that but an easy thing to check if you can borrow some coil packs from someone.

I would check fuel pressure next. It sucks on this car because it does not have a port that fits a standard gauge adaptor like most cars do, so you have to buy the adaptor parts from Honda. Or you can drill and tap the rail and just install a gauge there. But in any case, need to make sure you have good fuel pressure.

If fuel pressure is good, yes I would have your injectors checked and cleaned to make sure that is not part of the issue. And replace the seals on them when you pull them and have them tested. They are prone to leak sometimes if you try reusing them (and the seal kit is cheap).

Not a bad idea to check valve adjustment as it is easy to do. May not be the cause of this unless it is way off and unless you have recently adjusted them (but it has been a year), should not have gotten way off on all cylinders but worth checking.

I would also have a leakdown test performed.

 

So the mechanic said he tried new coil packs and tried swapping them around the cylinders but cylinders 2 and 3 remained weak (especially 2). I'll write down what you said about the fuel pressure test though and let him know.

 

Valve adjustment needs to be done on a cold engine and set to the loosest setting as they tighten in use. Intake 0.010" (0.25mm), Exhaust 0.011" (0.29mm). AP2 DBW engines (2006+) benefit by setting the exhaust 0.001" over-loose to 0.012" (0.30mm) (sorry, I can't think of a better term than "over-loose" this morning on my first cup of coffee) and none suffer this loose.

"Rebuilding" this engine rarely succeeds especially when the rebuilder seems to know little about them as your mechanic seems to know by even suggesting this. Valve clearance check would be my next step. Engine no warmer than 100°F and just bringing it into the garage will exceed that.

-- Chuck

 

Any mechanic that wants to tear into engine w low compression, yet hasn't done a leakdown first, shouldn't be allowed to work on your car.

As stated, rebuilding this engine is not likely to succeed. An exploratory disassemble is not going to be very useful.

 

if your showing low compression i dont think plugs or coils are going to do much so I would move on from there. i would check the old plugs for damage though. there was a mention earlier about an injector possibly sticking and that could have washed down the cylinder causing maybe a lower number but i think you could be seeing some additional smoke out the tail pipe maybe even a catalyst code pop up in addition to a misfire. There are a number of things they could do without tearing down to possible better diagnose the situation first. If i were working on it, i would throw a camera in the sparkplug hole and get a good look at the condition of valves, the bore etc. if im not seeing something from that a leak down is next up. maybe even rotate the motor to close the valves and throw some smoke at the intake side to see if i see anything coming up the sparkplug hole. Hopefully its a little bit of carbon build up on a valve. best of luck.