The O-rings at the injector won't fix the leaky-injector situation. Each injector has 2 O-rings, as follows:
- Top one seals the injector into the fuel rail. That one would result in fuel leaking out between the rail and the injector, where you would smell gasoline in the engine compartment.
- Lower one seals the injector where it's inserted into the intake manifold. That one would result in a vacuum leak, where air is being sucked into the manifold alongside the injector. Maybe that's your hissing sound, but it doesn't really explain why it only has a problem on warm starts.
You could use a scrap piece of garden hose as a poor-man's stethoscope, and try to pinpoint the location of the hissing sound. If it IS the injector lower O-ring, then I'd replace all 4 uppers & all 4 lowers.

Cleaning the injectors is a possibility, but you may see improvement by putting some "fuel injector cleaner" stuff in the fuel tank. I like Chevron Techron, but others may argue brands. I don't really have data to back up my choice. If that helps, but doesn't fully resolve it, you could use more in the next fuel fillup, or you can check out having them cleaned ($$).

 

Nothing that I can recall. Will get the codes read. I do have OBD reader installed (as part of metromile per-mile insurance, they've been sending the P1486 notifications all this time).

 

Thanks for explaining. I'll try the fuel injector cleaner before anything.

 

I'd also keep looking for the location of the hissing sound. I don't quite know how, but maybe the leak is somehow happening when the engine compartment is warm. In any case, if there's a vacuum leak you should fix it.

 

Sorry I may've not been clear earlier - hissing sound is when I start the car independent of whether engine is warm, cold or hot and it goes away after a minute or two, struggle to start is only when engine is warm. Just wanted to clarify in case it gives any clues to engine start issue.

 

OK, fair enough. I used to have a 1998 4-cyl Accord and never noticed a hissing sound like that so I assumed(?) it might have something to do with it.

 

Some updates - showed car to 2 diff mechanics locally. No clear diagnostics but wanted to share their comments & get your feedbacks.

There is small oil leak from distributor cap rotor assembly (they didn't if that'd cause any of my issues). Regd engine struggle when warm he said it is because of dirty spark plugs since I haven't changed them in all these years (not sure if that was the problem why I'd face that only when engine is warm and not always). Anyways, regardless of problem he recommended I change cap/rotor plugs ($400) and valve cover (+ $150) as required maintenance item.

He read out check engine light code and thermostat/cooling system malfunction is what came out. Coolant was low. He said that attempted fix sequence is thermostat+sensor then water pump then radiator itself may have a leak and since I have already done thermostat/sensor and given coolant was low may be there is a leak and I may need to change radiator if water pump change doesn't fix it. He also said that given I drive the car so little distance and so infrequently the cap gasket may also be not in good shape and he'd suggest I get cooling system issue fixed first. He also mentioned I could try pouring down some sort of liquid (I forget exact name) that goes down in radiator and can plug small leaks if there are any.

He said I could push out timing belt/water pump further out as belts can last up to 150k miles (even though he earlier said and I also saw that current one has started to crack). I guess he said I could push out coz of cost as timing belt/water pump is $750 and worst case engine goes down and I could put new engine for ~$1200. I am thinking of going ahead with getting timing belt _ water pump changed given belt looked like starting to crack at edges and deal with cooling system malfunction indicator later (next year when I need to clear smog check again) as car has been working fine for 4 years without any problem. What do you all suggest?

Regarding hissing sound, he said it is probably from air filter and nothing to worry about (he didn't hear it, with windows down and door open he probably couldn't even if he tried).

Second guy said valve cover gasket doesn't seem necessary but he can do if I want. What would you all suggest regarding changing valve cover gasket?

I asked this second guy about transmission fluid change. He said yes it'll take 3 rounds of changes to flush out but that he just needs to drive around for 5-10 minutes after each change for transmission fluid to circulate so he can drain & fill again. From what I had read one has to drive around few weeks before doing next round of drain/fill. Is it true that drain/refill is ok after few miles of driving?

 

I'd recommend getting the timing belt & water pump replaced. The valve cover gasket can be replaced, because the valve cover is removed during this process.

Since you were missing coolant, you should get a loaner radiator pressure tester kit as a loaner tool from a parts store. You put down a deposit, then get a full refund when you return the tool. Pressure test the radiator to 1.1 atm (16 psi) and see if the cooling system can hold the pressure. Also test the radiator cap to see if it holds pressure. The cooling system should hold pressure up to 16 psi, then release the pressure. This is a simple test that you can do. Make sure the engine is cold when doing this.

Do not add any kind of sealer to your radiator, because the fix is not effective. Better to just fix the problem.

There should be no oil inside the distributor. You may need to replace the o-ring on the distributor, which is very easy to do. The grommet in the housing could be leaking. Replacing is possible, but it is more difficult. It is much easier to get a used distributor and install with a new o-ring.

Replacing the cap, rotor, and the spark plugs is a pretty simple to do yourself, but certainly won't hurt. Address the oil leak in the distributor first, before doing the cap and rotor.

 

Oil leaking from the distributor cap means oil is getting in there through the distributor shaft seal. That's possibly a new distributor (not just cap & rotor) which explains why the cost is so high.

If the valve cover gasket isn't leaking I'd leave it. The gasket gets hardened with age & heat, but that's only a problem when you open the valve cover & expect it to re-seal.

I don't like the sealant goo that you pour in the radiator. Maybe it's just me, but I'm afraid of that stuff causing other problems.

If the timing belt is starting to crack, I wouldn't put that off. If it jumps time & bends some valves, then you're stuck on the side of the road - somewhere...

In between drain/fill of ATF, you really only need to get the fluid mixed up. Driving around for 10 minutes is far better than simply leaving it up on the lift, starting the engine, and shifting through the gears (which some people do). Other people wait a few days in between simply because that might be more convenient for their schedule.

Once the ATF is clean, you can establish a 1x drain/fill interval that's good enough to prevent it getting very dirty to begin with.

 

I agree 100% with both PA and Jim. Do the timing belt AND the water pump together (Honda recommends doing both at the same time), as the timing belt runs the water pump.Get a valve cover cover gasket, since you have to remove it anyway to get the timing cover off. I'd also get a balance shaft retainer kit and have it installed while I have the timing cover off. It's a good idea to have one, it's cheap to do, and it's the perfect time to install it. I'd do plugs for sure. Like Jim mentioned the seal inside the distributor might be starting to get worn, hence you oil mist inside. It's really your call on replacing it or letting it go for a while. It really depends on how much oil mist is inside it.
I should add I don't like dumping stuff into the radiator. I prefer to fix it correctly.