[Maraz52]

Hi,
I had a problem posted in May, 2008 about engine misfire cylinder 1. We had done the tune up, and unhooked battery to reset the computer. Well, now engine warning light has been flashing a few times when I would drive it and sometimes it ran really rough, I could go 45 mph, then it would straighten out. Dealership said now an error code showed up that the catalytic converter is failing. I don't want to just replace the catalytic converter if something is causing that to fail and have it fail again. Also, are aftermarket converters as good as standard Honda ones? Also, how do I tell what engine is in this Honda EX, standard shift car? Thanks.

[TxGreaseMonkey]

. Engine misfire cylinder 1--consider replacing spark plug (NGK only) and coil.
Constant misfiring could damage a converter by polluting it with unburned fuel.

. I'd buy whatever converter is the best value (price and warranty).

. Engine code is stamped on the engine block, usually just left of the exhaust heat shield.

[Maraz52]

We had a garage replace the converter with an aftermarket one, and they also replaced the oxygen sensor. Wonder if the O2 sensor was the problem in the first place? Thanks for all the advice! I do appreciate all your experience and postings Txgreasemonkey

[this8384]

What year and model is your vehicle? Tx is right; not doing a tune up in a timely fashion could very well have damaged the convertor; however, a plugged converter won't "straighten out" over 45 mph, as you said your vehicle is doing. Also, an O2 sensor won't cause a cylinder misfire. Do you know which codes were present when the computer test was done? Having those help a lot with online diagnosis.

[Maraz52]

Codes 0301, 0302,0303, 0304, 1399

We replaced the ignition coil. Then got code for misfire cylinder 1 only. We replaced the new sparkplug wires and distributor and rotor with Honda parts, and new spark plug for cylinder 1 (NGK). It ran OK for about 250 miles. Then it is running rough after me driving 60 miles, when it was going 25 mph through our little town. Today, it ran rough on turnpike going 65 to 70 mph but not enough to throw error code again. Any more ideas? This is frustrating. Thanks.

[this8384]

The first four codes you listed are all misfire codes, pertinant to each cylinder. However, if you truly have a converter problem it should be throwing a 0420 code, not a 1399. When you say you replaced all the ignition parts(plugs, wires, etc.), did you replace them all within a short period? Or did you do one thing first, drive the vehicle for awhile, and then try something else? If you didn't do it all at once, it could have caused one of the parts to fail prematurely because it was overcompensating for the parts that had yet to be replaced.

You can tell which engine is in your vehicle by a few different ways. You can check the VIN number; the 8th digit is the engine code. If your hood is original, there should be a sticker underneath it with that information printed on it.

[Maraz52]

HI
We replaced the wires, plugs, distributor cap and rotor first when we had the first cylinder 1 misfire. Then we got multiple misfire codes and finally a code for ignitor failing. We replaced ignitor. Continued to misfire. We put Sea Foam motor treatment in gas twice. All this time, intermittent misfire and sometimes engine warning light would flash. Took it to dealership and they said it was cylinder 1 misfire, happened at 500 rpm, which was when I first started car that morning. They suggested replacing sparkplug wires but we didn't at that time. A few days later, another engine warning light. Took back to dealership and they said a code showed up for catalytic converter was bad and that was causing my problems. I said I don't think so.

Took it to a local repair shop after they promised to look into it. They had it 2 days and said it must be the catalytic converter since nothing else showed up. I said go replace it, they did with aftermarket one. And they also replaced the O2 sensor then, one by cat. Converter I assume. Car ran great for 6 weeks. Then it started having subtle misfires while I was driving at highway speeds, then got to doing it at 35 mph also. Finally engine warning light came on. Took it to AutoZone and code read cylinder 1 misfire. I went to Honda dealership and bought their sparkplug wires, distributor cap and rotor, and 1 sparkplug (NGK) from them for cylinder 1. Worked great for a week. Now subtle misfire at 65-70 mph at turnpike speeds, then misfire driving through town at 35 mph but no warning light. This morning engine warning light flashing after starting it in driveway. Hubby drove it to work with it flashing. He didn't notice a misfire while driving but warning light flashed.

Engine is 1.6 liter, 1998 Honda Civic EX with 5 speed manual transmission.

[Maraz52]

Oh I forgot we replaced the ignition coil right before I bought the last plug wires, spark plug and distributor cap/rotor.

[this8384]

This is a stupid question, but I assume you did properly gap the spark plugs before installation? Have you checked the wires to make sure that they weren't routed improperly and are being rubbed through from vibration as you go down the road?

[Maraz52]

Hi
Hubby checked the gap and it was within specification he said. Wires are properly attached, we double checked that already. They are fitting snugly and are in the guide things which come with the wires.
Car works fine for a short time when we do these repairs. Just no real answer. We haven't replaced the distributor yet. Problem seems to come back to misfire cylinder 1 most of the time.

[CaptainRich]

What I'm reading here is you are being told that the problem is the converter and/or sensors, but those have been replaced and the problem comes back.

You didn't mention how many miles you have on your car...
Has anyone at any of the shops you've been to suggested testing/cleaning the injectors? Or perhaps doing a leak-down test on the engine?
Are you burning oil or coolant excessively, etc?

While the converter could be part of the problem, it won't likely cause all of what you're experiencing. I've never seen a failing converter cause a subtle misfire at highway speeds.
You need to get the mechanical part of the engine diagnosed.

[Maraz52]

HI
1998 Honda Civic EX, about 133,000 miles, 1.6 liter engine, 5 spd. Salt corrosion on motor, since it was from snow belt area of Cleveland, Ohio. Not using oil. Gets 36 mph with turnpike driving speeds of 65 to 70 mpg when running good.
Nobody at these garages has really checked anything out, go by computer. I told them something caused the catalytic converter to go bad, probably me driving with engine warning light flashing.
History of car:
I got it from my daughter who bought it used. Car had a subtle occasional misfire when driving at highway speeds, like a hiccup when we first got it from her. Since I have owned it, I had the belts and radiator hoses replaced. There was a squealing screeching noise when car was started in cold weather. They replaced the timing belt at that time also, aftermarket part. Still had occasional strange sound when starting the car. Other unusual sound was a popping sound that happened once as I was driving on a very cold day, about 6 miles from my house. Car didn't overheat or anything so I kept on driving. WE also replaced spark plugs, wires and rotor/distributor cap when we first got it, aftermarket parts.

Car idled strange at times, when I was slowing to pull into parking spot, almost stalling. This happened intermittently. We replaced fuel filter then. Just had occasional idle problem that persisted and occasional misfire when driving but no engine warning lights.

15,000 miles after our tune up, it started running really rough as I was driving at 55 mph. It slowed to 45 mph, missing a lot and I couldn't go any faster, for about 5 miles. No engine warning light. It then started running OK. Engine warning light came on next day. It said misfire cylinder 1. I took it to a shop, where guy was a former Honda mechanic. He said it only needed a tuneup. I took it home, we did the plugs, wires distributor and rotor again.

1 week later, same issues and engine warning light would flash at times. Took it to AutoZone and had random misfires, P0301,0302,0303,0304, 1399. We got some Sea Foam to see if it was bad gas. Worked fine for another week. Same thing, runs rough when driving then straightens up.

Took it back to AutoZone. It said ignitor was failing along with the engine misfire codes.
We replaced the ignitor. Worked fine for about a week again. Same misfire deal

I went to a Honda dealership, had it looked at by them. They said it was misfire cylinder 1 which occurred when I started the car or shortly after. Happened at around 500 rpm. They suggested getting new Honda spark plug wires and hinted the distributor could be the problem.

They reset the error code. I drove home 15 miles no problem. Started towards work, 2 miles from home and engine warning light came back on. Seemed to run OK, not flashing so I drove to work. We tried another can of Sea Foam in gas.

I took it back to Honda dealership since they said they wouldn't charge for the repeat scan if it happened soon. Now it said a code for catalytic converter failing and they were sure that was causing my problem. I said I don't think so, called a local garage and they said they would look into the motor for me. They had it 3 days and said converter sounded likely to them also. So I said replace it, with aftermarket one and they also replaced oxygen sensor I am assuming which was by the converter.

Car ran great for 6 weeks. Then acted up again when driving, getting worse each day at highway speeds and acting up driving 35 mph in town also. We replaced the ignition coil. Ran great for a week, then intermittent problems again. We replaced the spark plug wires, distributor and rotor and spark plug 1 with genuine Honda parts. Car ran great for 1 week. Then 3 days of intermittent problems, engine warning light started flashing right after car was started. Hubby drove it to work with it flashing. Light stayed on when he drove it home but it didn't flash. Haven't checked the codes yet on this one.

:)

[this8384]

Try putting a bottle or two of injector cleaner into your gas tank before filling up.

Like Rich asked, has the car been using coolant and/or overheating?

[twinkiedooter]

Try putting a bottle or two of injector cleaner into your gas tank before filling up.

Like Rich asked, has the car been using coolant and/or overheating?

Excessive use of injector cleaner in a small 4 cylinder engine is NOT good advice. You can only use this type of cleaner just so many times before it can damage your engine, and you have a small 4 cylinder engine to boot and adding several bottles at once to a small gas tank is a sure way of screwing up your engine. You have already added the Sea Foam stuff and that didn't work. Your next step if you think the injectors are clogged would be to have them professionally cleaned right.

Have you looked into your fuel pump being faulty? From re-reading your original problems with the car above, I am really tending towards the faulty fuel pump as my car was doing some strange things just like you described and then the fuel pump finally quit altogether on me and had to be replaced. It would stand to reason that when you were putting along at 55 and then dropped down to 45 your engine had some sort of restriction of your fuel availability caused by a faulty fuel pump. Same thing with your just about stalling out when parking the car. My car did the same thing.

Car codes are wonderful and all but from what the codes exhibited was essentially your engine compensating for the fuel restriction due to a faulty fuel pump.

Also, how far away is your job in that the car does not properly heat up and is shut down. I had a job 2 1/2 miles from my home and the engine would not get to the proper operating temperature before shutting the engine off. That is extremely hard on a car. I had to replace my muffler and exhaust pipes due to this. Now I work 1/2 hour away and my car actually runs much better. The best thing to do if you live so close to your job would be to run your car for at least 1 hour on the weekends if possible. I did this trick but my engine still got "wore out" from all the turn it on and turn it off too soon stuff.

[this8384]

Excessive use of injector cleaner in a small 4 cylinder engine is NOT good advice. You can only use this type of cleaner just so many times before it can damage your engine, and you have a small 4 cylinder engine to boot and adding several bottles at once to a small gas tank is a sure way of screwing up your engine. You have already added the Sea Foam stuff and that didn't work. Your next step if you think the injectors are clogged would be to have them professionally cleaned right.

Have you looked into your fuel pump being faulty? From re-reading your original problems with the car above, I am really tending towards the faulty fuel pump as my car was doing some strange things just like you described and then the fuel pump finally quit altogether on me and had to be replaced. It would stand to reason that when you were putting along at 55 and then dropped down to 45 your engine had some sort of restriction of your fuel availability caused by a faulty fuel pump. Same thing with your just about stalling out when parking the car. My car did the same thing.

First off, nobody suggested "excessive use" of injector cleaner; I said try a bottle or two. Two bottles in one gas tank is not going to damage your engine.

Secondly, if his fuel pump was bad, it's not going to come up with a misfire on only one cylinder. Also, the problem would not rectify itself by performing a tune up. If it was actually a weak pump, it would get worse because now the ignition parts are firing better than before but there would still be a lack of sufficient fuel.

[linlee1]

Don't forget about the O2 Sensor when the engine light comes on or the engine cuts out. Could be the problem.

[Maraz52]

Problem was the fuel injector cylinder 1. Replace that and car has been running fine. Now we have a problem with it cutting out at highway speeds on freeway. Going about 3500 rpm and suddenly it stops down to 2500 or slightly less rpm for a few seconds. Does this off and on and then straightens out. I now have 157,000 miles on it. Last fill up was almost 37 mpg.

I had timing belt replaced about 105,000 miles but guy only replaced the belt. I asked why he did that and he said it didn't need the rest. I said Honda always does. Could my symptoms be timing belt problems. Or is it distributor? I am frustrated, another intermittent problem with no engine warning light at all coming on.

[dwoodsgirl]

I am having Cylinder 1 misfire also. I am wondering if you recently had a timing belt replacement? That is the last service I did before this warning.