CEL light and misfire codes problem
12-19-2003, 09:36 PM
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CEL light and misfire codes problem
About a week ago I got my battery replaced. Two days later the Check Engine Light came on. I brought it in to the dealership and they pulled the codes from it, it was codes P0301 through P0304, meaning that the car had misfired all four cylinders. They cleared the light and it did not come back on during their 9-mile test drive, so I took the car back. Later that day, sure enough, the light came back on.
So the next morning I brought it back. This time they did a much more thorough diagnostic. This time they were able to get the information on when the misfire code was triggered. Apparantly it happened at 13mph and at 933rpm. The only time the RPMs are that low at that speed (unless the test driver ran it in 6th at that speed for some reason) is with the clutch in, when braking for a stop (which causes the car to go to idle).
They called into the west coast Honda branch (not sure what that is, it's the hotline when the service dept. need help), and they suggested a possible bent valve. They ran a compression test, one cylinder read 10%, two more at 12% and one more at 13% (the engine is supposed to run at 10% or less).
The engine runs great, at least to my ears (after 62,000 miles of driving it), and they said so too. A bent valve is unlikely to cause all four cylinders to be off, unless all four cylinders had bent valves, which would imply damage rather than a manufacturing defect (such as overreving the engine). However, I have never misshifted from redline, and the only misshifts were from 6k or so and all were caught. Thus, if the car was misshifted, it was misshifted when not in my control (joyride during a service? joyride before I bought it?). In either case, a bent valve should cause the engine to run rough, and consistently cause a misfire, if I understand my engine physics correctly. At any case, a bent valve should be a consistent problem, shouldn't it?
I'm hoping the compression issue can be resolved with a simple valve adjustment, as the valves have not been adjusted in at least 62,000 miles.
Researching on this forum yielded two examples of people with similar problems:
http://forums.s2ki.com/forums/showthread.p...threadid=114971
http://forums.s2ki.com/forums/showthread.p...threadid=118958
In both cases the problem appeared to be bad injectors. Tonight, after the CEL light lit up again, I parked the car and left the engine running. I popped the hood and listened to the engine. The engine sounded normal, just like every other time I listened to it over the last 62,000 miles. However, when I went to the exhaust, I heard an intermittent puffing/popping sound. It's kind of like if you clamp your lips, blow, then relax the lips, that kind of sound. Very soft, and very random. It'd go for several seconds, make the nouse, then half a second, noise, etc, no noticable pattern. If a bent valve was causing this, wouldn't it have a regular pattern?
So what could be causing the puff noise at idle? The car runs fine when driving. I haven't pushed the car (and won't until I diagnose the real cause), but I notice no power loss, and the engine runs as smooth as it ever did (when not at idle).
I'm definitely hoping it's not a valve problem, because that's a $5000+ repair job (involving replacing the top part of the engine). The car is out of warranty, so any repairs are at my expense. If it is that serious, I'll be forced to drop out of graduate school and go back to work so that I can afford that bill. I doubt the battery repair had anything to do with it. The only change I can think of that might matter is the fact that I switched from Texaco/Chevron 93 octane gas to Exxon 93 octane gas (about 10 cents cheaper/gallon around here). Could the new gas be poorer quality gas, and be accentuating an existing fuel supply problem?
Anyway, I wanted to post this to add to the knowledgebase of S2k problems. I'll post follow-ups as more information is available.
If anyone knows what could cause the puffing noise, please let me know. Also does anyone know if misadjusted valves can cause excessive compression test leakage? Thanks!
So the next morning I brought it back. This time they did a much more thorough diagnostic. This time they were able to get the information on when the misfire code was triggered. Apparantly it happened at 13mph and at 933rpm. The only time the RPMs are that low at that speed (unless the test driver ran it in 6th at that speed for some reason) is with the clutch in, when braking for a stop (which causes the car to go to idle).
They called into the west coast Honda branch (not sure what that is, it's the hotline when the service dept. need help), and they suggested a possible bent valve. They ran a compression test, one cylinder read 10%, two more at 12% and one more at 13% (the engine is supposed to run at 10% or less).
The engine runs great, at least to my ears (after 62,000 miles of driving it), and they said so too. A bent valve is unlikely to cause all four cylinders to be off, unless all four cylinders had bent valves, which would imply damage rather than a manufacturing defect (such as overreving the engine). However, I have never misshifted from redline, and the only misshifts were from 6k or so and all were caught. Thus, if the car was misshifted, it was misshifted when not in my control (joyride during a service? joyride before I bought it?). In either case, a bent valve should cause the engine to run rough, and consistently cause a misfire, if I understand my engine physics correctly. At any case, a bent valve should be a consistent problem, shouldn't it?
I'm hoping the compression issue can be resolved with a simple valve adjustment, as the valves have not been adjusted in at least 62,000 miles.
Researching on this forum yielded two examples of people with similar problems:
http://forums.s2ki.com/forums/showthread.p...threadid=114971
http://forums.s2ki.com/forums/showthread.p...threadid=118958
In both cases the problem appeared to be bad injectors. Tonight, after the CEL light lit up again, I parked the car and left the engine running. I popped the hood and listened to the engine. The engine sounded normal, just like every other time I listened to it over the last 62,000 miles. However, when I went to the exhaust, I heard an intermittent puffing/popping sound. It's kind of like if you clamp your lips, blow, then relax the lips, that kind of sound. Very soft, and very random. It'd go for several seconds, make the nouse, then half a second, noise, etc, no noticable pattern. If a bent valve was causing this, wouldn't it have a regular pattern?
So what could be causing the puff noise at idle? The car runs fine when driving. I haven't pushed the car (and won't until I diagnose the real cause), but I notice no power loss, and the engine runs as smooth as it ever did (when not at idle).
I'm definitely hoping it's not a valve problem, because that's a $5000+ repair job (involving replacing the top part of the engine). The car is out of warranty, so any repairs are at my expense. If it is that serious, I'll be forced to drop out of graduate school and go back to work so that I can afford that bill. I doubt the battery repair had anything to do with it. The only change I can think of that might matter is the fact that I switched from Texaco/Chevron 93 octane gas to Exxon 93 octane gas (about 10 cents cheaper/gallon around here). Could the new gas be poorer quality gas, and be accentuating an existing fuel supply problem?
Anyway, I wanted to post this to add to the knowledgebase of S2k problems. I'll post follow-ups as more information is available.
If anyone knows what could cause the puffing noise, please let me know. Also does anyone know if misadjusted valves can cause excessive compression test leakage? Thanks!
12-19-2003, 10:08 PM
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has the car ever set long in the cold without drivetime. many times, misfire codes come from the car being too loaded with fuel. if this happens, misfie codes usually showup on cylinder#1 or #4, not on all four. just for kicks, put new plugs in, hot gas and run the hell out of it......
12-19-2003, 10:30 PM
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The car hasn't sat for more than a day in the last six months. It's my daily driver and only car, so it sees a lot of use.
I do recall the last tank of fuel filling the tank completely (saw gas bubbling up just as the shutoff on the pump kicked in). And the car is always parked on a hill. The first time the CEL turned on I was 80 miles into that tank. That tank is almost empty, so I'm going to switch back to my regular gas station tomorrow and see if that has any effect.
I do recall the last tank of fuel filling the tank completely (saw gas bubbling up just as the shutoff on the pump kicked in). And the car is always parked on a hill. The first time the CEL turned on I was 80 miles into that tank. That tank is almost empty, so I'm going to switch back to my regular gas station tomorrow and see if that has any effect.
12-19-2003, 10:37 PM
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Some car details, for the record:
62,500 miles on the odo a few days ago.
White/Red '01, last 4 digits: 0401. If I remember, I'll go out and get the serial number of the engine.
Bought car at 350ish. Car was delivered to a dealership in Oklahoma, dealer transfered to Ft Worth, Texas, where I bought it.
The car is completely stock, except for the Titanium Shift Knob, a Muz Mat, a Honda alarm system, and some netting in the trunk.
Hit the rev limiter 3 times (accelerating the car, the upshifts were normal), redlined the car many times. No track days. Fastest speed I've driven it: 110mph.
History of problems and TSB fixes:
TSB 54 (Clutch Rattle) done at ~30k
Driver side window auto-down failed and replaced at ~36k
Spark Plug Recall completed at ~40k
Rear Plastic Window cracked when lowering top at ~60k
Maintenance followed to the letter, oil changes every 3,750 miles.
Man I miss VTEC!
62,500 miles on the odo a few days ago.
White/Red '01, last 4 digits: 0401. If I remember, I'll go out and get the serial number of the engine.
Bought car at 350ish. Car was delivered to a dealership in Oklahoma, dealer transfered to Ft Worth, Texas, where I bought it.
The car is completely stock, except for the Titanium Shift Knob, a Muz Mat, a Honda alarm system, and some netting in the trunk.
Hit the rev limiter 3 times (accelerating the car, the upshifts were normal), redlined the car many times. No track days. Fastest speed I've driven it: 110mph.
History of problems and TSB fixes:
TSB 54 (Clutch Rattle) done at ~30k
Driver side window auto-down failed and replaced at ~36k
Spark Plug Recall completed at ~40k
Rear Plastic Window cracked when lowering top at ~60k
Maintenance followed to the letter, oil changes every 3,750 miles.
Man I miss VTEC!
12-20-2003, 03:36 AM
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im asuming youve had the fuel filter changed. the next thing id do is try an injector cleaning. not a bottle of stuff you get from a parts store, but a good cleaning from the dealership. you have a problem that affects all cylinders. i dont believe you have a bent valve, because it would be audible at all speeds of the engine.
also, i have a question for you. you had your back window replaced due to cracking? my window EXPLODED the other day when i lowered the top. im kinda pissed. did they give you any guff?
also, i have a question for you. you had your back window replaced due to cracking? my window EXPLODED the other day when i lowered the top. im kinda pissed. did they give you any guff?
12-20-2003, 09:23 AM
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Hoof,
The data you give (933 rpm and 13 mph) only states when the actual light came on (this is an OBD requirment). However, it does not specifically mean that the problem also only occured during these conditions!! The OBD system has already started logging the problem internally well before the light came on. It's the way the system works. It's looking at varying crankshaft rotation speeds, which are not normal and regular. So don't pay too much attention to that information i.m.o.
I would first focus on the valve adjustment. I've heard some comments by my dealer that over 40k miles the valves could be out of spec already. Since mine is not even near that kind of milage, I'm assuming he isn't talking BS. Another Dutch member here already had his valves adjusted after they discovered they were a pretty amount off.
Secondly, I would check the spark plugs as well, as I would normally focus on an ignition problem.
Good luck and keep us posted!!!
Siepel
The data you give (933 rpm and 13 mph) only states when the actual light came on (this is an OBD requirment). However, it does not specifically mean that the problem also only occured during these conditions!! The OBD system has already started logging the problem internally well before the light came on. It's the way the system works. It's looking at varying crankshaft rotation speeds, which are not normal and regular. So don't pay too much attention to that information i.m.o.
I would first focus on the valve adjustment. I've heard some comments by my dealer that over 40k miles the valves could be out of spec already. Since mine is not even near that kind of milage, I'm assuming he isn't talking BS. Another Dutch member here already had his valves adjusted after they discovered they were a pretty amount off.
Secondly, I would check the spark plugs as well, as I would normally focus on an ignition problem.
Good luck and keep us posted!!!
Siepel
12-20-2003, 10:18 AM
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Sorry to hear about your window exploding solar.
No I haven't replaced the back window yet. The upolstery shop the Honda dealership pointed me towards said it would be at least $800 to replace the window. I doubt that number is accurate since they assume that the entire top had to be removed (about 16 hours of work).
From looking at the window, it seems that the top shouldn't have to be removed, but the interior would have to be disassembled somewhat to get to the lower connection point of the window. The upper portion is connected via a zipper, however I do not know whether that zipper would help in replacing it or if it a car construction convenience.
Currently I'm using some transparant packing tape applied to both sides of the two cracks. That's been holding the rain out, and as long as I'm careful lowering the top (making sure it doesn't kink), it should hold me out until I'm finished with grad school and can afford to fix it.
No, the fuel filter hasn't been changed yet. It's on the list of things I'm going to ask the dealer shop to do on Monday. I'm hoping to get the following done on Monday:
1) fuel filter replaced
2) spark plugs checked (correct clearance, whether they're clean or not)
3) valves adjusted
4) injectors inspected/replaced
Hopefully that won't be too expensive and I can resolve this issue once and for all.
No I haven't replaced the back window yet. The upolstery shop the Honda dealership pointed me towards said it would be at least $800 to replace the window. I doubt that number is accurate since they assume that the entire top had to be removed (about 16 hours of work).
From looking at the window, it seems that the top shouldn't have to be removed, but the interior would have to be disassembled somewhat to get to the lower connection point of the window. The upper portion is connected via a zipper, however I do not know whether that zipper would help in replacing it or if it a car construction convenience.
Currently I'm using some transparant packing tape applied to both sides of the two cracks. That's been holding the rain out, and as long as I'm careful lowering the top (making sure it doesn't kink), it should hold me out until I'm finished with grad school and can afford to fix it.
No, the fuel filter hasn't been changed yet. It's on the list of things I'm going to ask the dealer shop to do on Monday. I'm hoping to get the following done on Monday:
1) fuel filter replaced
2) spark plugs checked (correct clearance, whether they're clean or not)
3) valves adjusted
4) injectors inspected/replaced
Hopefully that won't be too expensive and I can resolve this issue once and for all.
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01-05-2004, 02:39 PM
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Now that the holidays are over and I'm back in town, I've been able to work this problem some more. Today I had the valves adjusted. A compression check afterwards indicated that the compression readings reported earlier were due to the valves. Now the cylinders are reading no leak (vs 10-13% before the adjustment). So much for the bent valves theory. However, when I parked the car after driving home, I could still hear the intermittent "puff" noise at idle. I'm hoping the valves were the problem with the CEL light, but I won't be surprised if that light comes back on. I'll report back in a few days as to whether it comes back on again. If it comes back on, then I'm guessing it's the injectors.
01-06-2004, 07:35 AM
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hoof, when the light came is it blinking or did it stay solid? I have heard of the check engine lights blinking when it is a misfire, is this correct or not? If it did blink did it ever turn solid or does it continue to blink while it stays on?
