For some time now my engine has been acting a little funny. It will idle fine for the most part but on some days it will idle a little rough and the exhaust will pulsate with a sort of "put put" sound. There is no noticeable loss in performance/power and the problem only exists at idle. When i full throttle it a few times the problem will go away and resurface about a week or so later. It's really strange.. i've changed the plugs, wires, distributor cap, and egr. I was thinking it might have something to do with the fuel system but I'm not completely sure. I also want to take it into honda but the problem is so intermittent that they might not be able to diagnose it. SOMEONE PLEASE HELP ME!!!

 

I would like to ask if you could give a better scenario of the idle time when the problem pops up. What is the weather, temp, humidity like. What do you think may be the same each time this happens, for example, it was rainy, or it idled in traffic for about three minutes or at the store for eight minutes with or without AC. As much info as you can give please. I already think that the O2 sensor is staying rich or lean and scewing te fuel mixture just enough to make it act up and throttling it gets the O2 sensor reading acurately again and it takes another same scenario to get it to act bad again.

Where is the idle fully warmed up and the AC off. Do you have a cheap multimeter you can put on the MAP sensor signal wire that tells the ECM how much vacuum you have at idle, you will need to make a long lead so you can keep the meter in the cabin with you. Maybe you need a valve adjustment, or did you have one recently, when was you last oil change, fuel in oil now????

 

The problem seems to occur sporatically at best and seems to get better once the A/C is turned on. There is no set pattern for it, it just does it out of the blue after driving it for a bit. I changed out the O2 sensor and the MAP sensor already. The oil has also been changed with no sign of gas being in it and a valve adjustment has also been recently done. There is, however, a smell of fuel when the problem occurs. I thought it would have something to do with the catalytic converter but i disconnected it before and the problem still persisted.

 

The O2S and MAP are the #1 and #2 misdiagnosed components on Hondas today, even if you have a code for an O2S, you still can prove that it is in good working order. You need to get scan data during a test drive my friend, quit wasting money on parts you dont need, how did you disconnect the cat, unbolt it and just let the exhaust leak from the gasket area???

 

Yah pretty much. I read somewhere that that's one of the ways to check for a clogged cat. What kind of scan tool should i purchase/use for this kind of situation? I would bring it in to honda but the problem is so on and off that I feel as if they'll be unable to diagnose it. I was running a supercharger sometime before and dumping a good amount of fuel into the engine during that time. I was told that it might be the fuel filter but I don't understand how (if the fuel filter was clogged) the problem would be an on and off sort of thing.