Dont give me the search crap. I searched and only found 2 articles, neither of which had a definitive solution!


Just did a tune up on my 98 Honda Prelude b/c I am about to drive across the country( I am moving). While driving the other day, I threw a code 71 while sitting at a stop light. My idle went from 800 down to 500. It sits at 500 rpm without any bounce. The misfire only seems to happen at idle, and only after teh engine is warmed up. It is a random condition. Sometimes it does it, sometimes it idles fine.

So far, I have replaced the plugs (twice), wires, cap, rotor, and air filter. I did a valve adjust, compression check, and ran fuel system cleaner.

I am going to change the fuel filter today. I am also going to test injector #1. It is functioning, b/c I hear it clicking but I am afraid it may be internally clogged or flowing insufficiently.

Other than this, I am completely stumped!!! So I am turning to you guys for help. The misfire is in Cylinder #1 only, and the only code being thrown is 71! This is driving me nuts!!

 

So it wasn't throwing the code before you tuned it up?

 

Aftermarket cams?

Using a VAFC or chipped ECU?

Made sure adjusting nuts on the vavles torqued correctly?

Need more info. OBDII VTEC ECUs can be VERY sensitive to "misfire" conditions.

 

Car and engine are completely stock!!! The car is my daily driver.