Hello! I recently purchased this car and it was running fine at first, there was a steering pump leak so I replace the power steering pump and serpentine belt. After these repairs I began to get a check engine light flash and then go solid. This light consistently gives code P0300, P0103 etc. for the cylinders. I replaced the spark plugs and coils, still got the error codes. Replace the air filter and 3 motor mounts (they were shot). I am still getting the same codes, I had a compression test run on my car and that was fine. Once the code is cleared the car runs great for about 50 miles or so, then the code comes back. Once he code comes back the car will be sluggish. I am not sure what to check next, I bought the new spark plugs from O'Reillys and I am not sure if they were bad? What can I try next? I am giving the full list of things I have done, even though some of it should not affect the misfires. Any suggestions would be appreciated.

 

P0103 is for the MAF sensor. did you mean to type P0301? that is more common along side P0300 which is why I ask.

if P0103 is accurate, try swapping that out and checking the air intake for leaks or blockages. If that doesn't help, swap the old one back in before continuing to diagnose.

 

Yes you are right I meant P0300, 301,302,303,304. I notice that the car runs fine before the check engine light comes on, then after the light comes on it does not run well anymore, if I clear the code it runs fine again, then after about 49 miles the code comes back, I just purchased the NGK IZFR6K spark plugs, I am hoping these will make a difference, I used some plugs from O'reillys and maybe the car does not like those?

 

Did you by chance drop any of the plugs? I was told many years ago that if you drop a spark plug there's a good chance that its bad and should be thrown out.

 

No I did not drop any of the spark plugs, but I did go ahead and replace the spark plugs. After driving for about 16 miles the check engine light came back on with the same group of codes. I am not sure what is going on. Do you have any suggestions?

 

I did notice that if I engage the clutch when the car is in 5th gear the check engine light comes on immediately. I can keep the car running w/o the check engine light for longer as long as when slowing down I only engage the clutch after 45mph. Is there a fuse/sensor inside the engine that might be bad? What might cause something like this? The car has 158,000 miles on it. Any ideas?

 

I don't think the clutch has anything to do with it. The P03xx codes indicate misfires - 0301 is cylinder 1, 0302 is cylinder 2, etc. This is most likely caused by bad spark plugs, a bad coil, or both. You replaced plugs and coils. Here is my ten cents worth, at least some things you might check:

1) You may have bad coils and/or plugs. I always use name brand parts, as a lot of the stuff you get on Amazon or from local car parts stores is junk, bad right out of the box. NGK/NTG is the best source of plugs and electrical parts in my opinion. Sixty Auto has NGK coil packs and plugs. They will cost you more - a LOT more - but they will work every time and last a lot longer than the typical junk you find all over the place these days.

2) Whenever something goes bad or stops working go back to the last thing you did. You replaced the steering pump and belt: Check that out again. The clearances in a Honda are tiny, you may have disconnected or dislodged something, or even gotten some PS fluid in something. I think this is unlikely but that's the first thing I'd check.

3) Not knocking O'Reillys, I buy stuff from them all the time, but unless you are very specific with them you may (will probably) get cheap parts. That's not their fault, you have to be specific. I get most of my car parts online because I get better quality than the auto parts stores and at a much lower price. Amazon is good, so is Rock Auto. Again the trick is DO NOT BUY CHEAP STUFF!!! Go with name brands or OEM parts. And stay off of FleaBay unless there is no other source.

4) Did you put something weird in the gas tank? Diesel? Some kind of miracle injector cleaner (guaranteed to f--- up your injectors)?

5) Totally ignore warranties on car parts. I cannot convince my nephew of this; he will buy something with a one year warranty and think he's gotten a good deal. The only thing a one year warranty on a car part means is, IF its honored at all you will be replacing that part every six months or so. Buy quality parts and ignore warranties.

Electrical stuff: NGK/NTG;
Belts, hoses, thermostat: Gates;
Pumps: Dorman or OEM
Oil: Mobil-1 or Valvoline
Oil filter: Anything except Fram
Coolant, PS fluid: Honda uses special stuff, just buy that

Good luck!