1998 Honda Prelude with a JDM H22A.

Car runs really well. No driveability problems, starts up every time. But the annoying CEL is on. Diagnostic says this:

P0133 O2 sensor circuit slow response Bank 1 Sensor 1

P0301 Cylinder 1 misfire detected

P0303 Cylinder 3 misfire detected

P0304 Cylinder 4 misfire detected

P0302 Cylinder 2 misfire detected

P0300 Random/multiple cylinder misfire detected

I should also probably mention that I'll clear the codes by pulling the 7.5 fuse. The CEL is off from the cluster. Then I'll drive around and once I hit 6000 RPM's, the CEL will start flashing.

Anyone else have/had this problem? Or what the problem could be? Any info will be helpful.

 

https://honda-tech.com/forums/showth...random+misfire
Basically it comes down to either the ignition system, or the EGR, start with the cheap stuff- cap, rotor, plugs, etc. and work your way from there.

 

I've replaced the cap, rotor, dist. wires.... haven't tried the plugs yet though.

 

Unless your plugs are fairly new, i would definately replace them also, and
i recommend NGK plugs.

 

NGK Iridium IX's are the way to go...allllllllllll day!

 

Any other inputs besides the spark plugs?

 

do you have a known good distributor you can test?

 

No I do not.

 

the distributor along with the EGR valve, or clogged EGR ports are both suspect in this case, no real way that I know of to test the distributor without swapping it out for a known good unit.

 

NO .. H22 engines work best when using NGK PZFR6F-11 plugs

 

The car does hesitate a little around 3k RPM's... could the clogged EGR ports be the problem?

 

If you are diagnosing a problem, go with the copper plugs. If everything is solid and you're not built/boosted then the iridiums will last longer with no real performance difference.

 

it is possible, if so then you are lucky and it is a simple fix.

 

clogged egr ports would turn on the 'insufficient egr flow' code. there is no way the egr could set all those codes unless the valve was stuck open all the time. i would guess crank position sensor since thats what detects misfires. is the spark timing adjustable on 5th gens? rotating the distributor too much could cause it, at least on older cars

 

Your first code was sluggish O2, did you replace this? If the o2 is not moving fast enough you could get a lean or very rich which could cause a miss but you might not feel it.. Granted you should look at the other stuff but O2s tell the computer how much fuel to add or subtract. Just curious but are the computers for the jdm the same as the US and which do you have?