nola000

2002 Honda Civic 260K miles

Problem

1. Wont start.
2. Once in a while when cranking and then letting off, the crankshaft will rotate a couple times on its own and then engine dies.
3. Sounds like its backfiring through the intake after it stops cranking.
4. When it was running it would idle very poorly when cold at first startup but would run great when RPMs were up or after just shutting it down.
5. Had to fill radiator reservoir about once a week. Didnt see it leaking anywhere. Possibly leaking into combustion chamber causing misfire or burning off from overheating? Noticed top radiator hose would get really hard and bottom soft. Maybe sticking thermostat?
6. When it was running it would overheat mostly with the AC on and/or when stopped. Think that is a separate problem as the radiator fan wouldnt come on on its own without AC fan on. Indicates a problem with radiator fan switch. The radiator/overheating issues might all be a separate problem, dont know.

Observations

1. Battery voltage good.
2. Plug on cylinder #1 looks good.
3. Plug on cylinder #2, #3 and #4 soaked in gas.
4. Switched coil packs around, no change.
5. Switched plugs around, no change.
6. Oil color looks normal, noticed some sludge on dipstick I hadnt seen before.
7. Compression checks out, I think. Its really high but it could be the cheap Autozone(Actron) compression tester I have. Should be 135psi with a 28psi variance between cylinders. I got #1=195, #2=190, #3=195, #4=200.

History

1. Had been getting misfire codes for a long time. Mainly cylinder #2 but also sometimes #3 and rarely #4 and more rarely(maybe never) #1.
2. Had been also getting P0420 catalytic converter code. My Honda mechanics manual says to solve the misfire codes first so Im guessing the misfire caused the P0420 and 0420 cant cause misfire or can it?
3. Had an exhaust leak behind catalytic converter where the flange weld broke causing a bad seat from exhaust manifold/cat. converter assembly to exhaust pipe allowing gasses to escape from around connection. Was like this for about 50K miles. Was making terrible ticking/clacking noise under load until I fixed the bad weld.

Parts Replaced

1. PCV valve - 1K miles old
2. Air filter - 1K miles old
3. Valve clearance adjustment - 1K miles old
4. TDC sensor 4K miles old
5. Radiator - 12K miles old
6. Spark plugs(NGK PZFR6F-11) - 17K miles old
7. Catalytic converter - 53K miles old
8. Alternator - 53K miles old
9. O2 sensor(primary upstream) - 68K miles old
10. Timing belt - 83K miles old
11. Water pump - 83K miles old

Any ideas? What should I attack first?

Mad Dog Tannen

Misfire will ruin the catalytic converter. The misfire probably caused the cat code.

It sounds like you have a ignition problem, cam sensors?

nola000

Wouldnt a bad cam sensor set off an OBD code?

I read that one way to diagnose no start/cam sensor is to unplug the cam sensor and try starting it. Does that sound right? Would it even start without a cam sensor signal?

mikey1

i absolutely HATE the term "turn over" as there are a million and one ways this can be taken, are we baking muffins? did you turn them over?

spray some kind of flammible liquid into the throttle body while somebody else cranks it, carb cleaner, throttle body cleaner etc etc......will the engine run while doing this?

ezone

lmfao!

Mad Dog Tannen

He said the pistons are soaked in gasoline, I don't think carb cleaner would do anything, It sounds like bad spark.

ezone

Agree, if the plugs are already wet.

Why would only 3 of them be wet?

mikey1

oh yeah.....sorry, i didnt bother reading that far

Mad Dog Tannen

Just because it is easy, you might want to see if your fuel injectors are cracked or damaged. They could be dumping too much fuel in there and making the sensors freak out. But I still suspect ignition is the real issue.

nola000

Wouldnt that ALSO set off an OBD code?

Fixed "turn over" for the semantically sensitive

ezone

Not necessarily.

nola000

I guess Im only getting spark in cylinder #1. Or at least a hot enough spark. I checked the ignition coil spark in all of them using a Thexton THE458. Saw a faint orange spark in all of them but not sure how accurate that process is. It was getting A spark just maybe not a STRONG enough spark. Dont know.

nola000

Do injectors ever dump too much fuel? It seems they could only get weak or clog over time causing them to not dump enough.

mikey1

a weak spark is just as bad as no spark at all,

you should ear a "snap" noise while it sparks

nola000

Would a weak coil pack throw a code?

ezone

Thexton....Dial-A-Gap? LOL

Spark should be evaluated by testing how wide of an air gap the spark can jump. Maximum gap measurement can then be converted to approximate kV output.


I'd use a simple screwdriver and a helper to crank the engine.
Insert screwdriver in the end of the coil, hold shaft near the valve cover (ground) and while someone is cranking it --slowly pull the screwdriver away from the valve cover to widen the gap while watching sparks. A good coil should be able to make a spark that will jump 3/4" or greater gap.

Only as a misfire code, and it's gotta run first in order to do that.

nola000

Thexton "LOL" has a scale on it. The coils were able to jump a 20kV gap. I dont know if thats good, bad or other. I didnt try to increase the gap but it IS adjustable. .

ezone

20kV should be sufficient.

nola000

So now what?

bsmiley

So spark isn't the issue. Its something else.

ezone

Remove the 4 coils and 4 spark plugs

What is the wetness on the plugs? Gasoline? Antifreeze?
(If it's antifreeze you're in trouble)
Post pictures of the plugs here

Dry the spark plugs.
Crank the engine over for 15 seconds without any spark plugs installed.
Pour one tablespoon of engine oil down each spark plug tube.
Lay a towel over the 4 plug tubes
crank the engine for another 15 seconds
remove towel
reinstall 4 clean dry spark plugs
see if engine will try to fire and run

nola000

I see where youre going with this. Awesome tips!

Im printing this out and taking it to the vehicle. About an hour away stranded at wifes workplace.

ezone

I was thinking maybe it's flooded and that's why the plugs are wet.

If it's flooded, maybe the rings have been washed down, need some oil to build the seal up again and restore compression.

You might want a set of plugs (cheap) just to get it started on if you can't clean and dry the others. A set of NGK ZFR6F-11 would be a cheap equivalent of the correct platinum plugs.

You posted some compression test numbers earlier, were those readings taken now that it doesn't start --- or were those taken sometime in the past?


EDIT: Take jumper cables with you!
And....learn how to work the throttle in response to if the engine fires or not.

nola000

NGK ZFR6F-11 are actually the plugs I use. Thats whats in there now(see my first post).

Those comp numbers were taken after the no start condition.

nola000

*UPDATE*

Replaced all 4 ignition coils. No change. So its not the coil packs.


All four plugs were soaked in gas. Before I only noticed the #1,3 and 4 gassed up.

The plugs I was using were actually NGK PZFR6F-11 not ZFR6F-11 as I stated earlier. The #2 cylinder plug which was the one that most often gave me a misfire code was black as coal and measured 3,790 Ohms. All other plugs looked brand new still and measured 4,000 Ohm.

I sprayed down the cylinders with B-12 carb cleaner.

Im about to pull the injectors to bench test them.

Could this possibly be a weak fuel pump? Yes the plugs are soaked in gas but is it possible there isnt enough gas or injector pressure to fire all four cylinders properly? Car has 260K miles and Ive never had the injectors flushed other than a bottle of BG44K in the tank once or twice years ago.

For years whenever I would get low on fuel (fuel light comes on) the car would be hard to start. Only time the car would ever be hard to start before it broke down completely. Like a weak fuel pump or clogged pickup screen.

nola000

It started. Dont know how or why. Still struggles to start after sitting. The longer it sits the harder it is to start. Im betting after it sits over night its not going to start again in the morning.

The only thing I did was take all the spark plugs out and spray down the combustion chambers with B-12 carb cleaner. Maybe it was flooded? How or why?

Just checked the fuel injector resistances. #1=14.2, #2=14, #3=15, #4=14. I guess thats fine. I was just looking for an outlier since my Honda Service Manual doesnt give specs for injector resistance.

I want to check fuel pressure but Im not going to buy that fancy proprietary gauge adapter that Honda sells for a small fortune. Anyone has or foresees a problem with cutting the rubber fuel line and splicing-in a brass tee with a schrader valve so I can use a standard fuel pressure gauge?

Elciteeve

Easy enough to test, just run a wire from your fuel pump relay to the battery with an in-line fused switch. Hook up the fuel lines that go to the injectors to a pressure gauge. That will tell you if you have sufficient pressure. You will also want to do a volumetric test to make sure you are getting enough fuel, as well as at the correct pressure.

If you are having to add coolant once a week and there are no visible coolant leaks then you possibly have a leaking head gasket or something to that effect, leaking coolant into the combustion chambers. Are you sure the plugs are soaked in gasoline and not coolant?

Elciteeve

I've always just fabricated my own as well. I didn't cut the existing fuel lines though, I added to them to create splits as needed.

nola000

How does one do a "volumetric test"? This isnt a procedure in the service manual nor does it give a fuel supply volume specification. I would imagine something like l/min.

That was my first thought. I would imagine that could be deduced by doing a pressure-hold test on the individual combustion chambers at TDC? Any thoughts on that?

The fuel fittings on the 7th gen are some kind of proprietary BS so I cant add-on. The fuel lines are all hardlines except for a rubber section in the engine bay right before the fuel rail. Im guessing this is the best place to splice in a schrader tee.

Elciteeve

I have a 7th gen civic as well. I know the fitting you are referring to, I added a hose over that section is what I am trying to say. Used a zip tie as a hose clamp so as to not apply too much pressure to that fitting, thus allowing for use of standard pressure gauges. You can't cut that line farther back as it's a line, and not a hose. I suppose if you wanted to get creative with your line splicing you could, but it's not as simple as cutting a rubber hose.

I don't recall the correct quantities (I'd have to look it up) but yes, there is a L / Minute rate of flow you want, while at a certain pressure.

Sounds like your compression is good, So I'm not sure what testing that further would reveal. If there is a leak somewhere then it seems small enough to leave you with good compression, and large enough to allow coolant into the combustion chamber.

You could try removing the fuel pump relay, crank the engine, see if there is additional "wetness" being caused. That would determine whether the liquid you are seeing is fuel or coolant.