Odd Missfire

[monkeydude3]

Okay... so I will describe this in the best way I can. 1990 LX automatic

Starting with a cold startup, lets say I let it run a few mins and then go right away. Drives fine, runs smooth. As it warms up, it developes a misfire. This is the only time it comes... 1500 rpm-2000 rpm on very light throttle while under load. Most noticeable is off idle in 1st gear, or cruising at about 35-45mph in 4th gear... THe hotter/more warmed up the car is, the more noticable this misfire. If I brake torque it, I totally feel it from 1500-2000 rpm.

The idle is at 900 rpm in gear, fully warmed up.

Any ideas? I'm thinking a vacuum line is a problem somewhere...

Thanks

George

[monkeydude3]

Any ideas? I'd like to get it fixed, because under normal sensible driving it's the most commonly used rpm range for me and the car shakes from it once it's hot... oye

[NAiL05]

Have you tried replacing your plugs and wires first to see if that solves the proble. Might as well do a lil tune up on it while your at it.

[monkeydude3]

well... when I did the timing belt, I did plugs, wires, cap, rotor. Loved it!

I mean if it wasn't for this peticular rpm range misfire under a load with light throttle, it runs perfetly fine otherwise. Could I need to adjust my valve lash? They are kinda rattly but no real bad noises.


Thanks!!!

[monkeydude3]

Well I am at a loss right now. Had a good look at all my vacuum lines and none seem to be leaking. What could be the cause? Car is warmed up, misfire under light throttle under load...

Maybe something with the ignition? Or still could I have overlooked a vaccuum issue.

Is this a problem anyone has heard of on our cars?

Thanks


George

[93EXaesthetic]

im having the same problem... cept when the CEL comes on .. it runs better.. i guess cuz the ecu dumps more fuel engine

[Ilikebigbutts]

in any missfire problem i get the first thing i look at is plugs and wires...pull the plugs and see if there is any arching on the white part from the wire...then i would move on to cap and rotor...

ILBB

[jhondayaaj]

you may want to clean out your egr ports. start with that.

[HondaFan81]

This start happening after the timing belt job? It seems like you're ignition components are working fine. Did you double check you're ignition timing and physical cam timing? Don't be stubborn, recheck them both and make sure.

[monkeydude3]

Believe me, timing belt timing was dead on. I marked the belts, the pullies, and all the lines were dead on. It's not that.

How would I go about cleaning the EGR ports? Is this overly complex, because I've been doing some reading and I think I need to check those too.

Plugs/wires are new... cap rotor I believe are new, I'm gonna pull off the cap sometime and see what we got under there.

Dang I just need time to do this crap

[Mealsy]

Found a Honda Service Bulletin for EGR Cleaning.
http://www.driveaccord.net/forums/at...p?postid=13440
(PDF File) This sounds exactly like your problem!

Also try your IAC Valve. Heres a thread (thanks to arrozburner) which is helpful. http://www.cb7tuner.com/vbb/showthread.php?t=30229

Good Luck!

[monkeydude3]

thanks guys. i've read that one, I'm in no mood to do all that to my beater. I may pull off the EGR valve and clean it and see what's goin on there, because knowing how EGRs work as I do it feels as if the EGR is stuck slightly open. But then again I have no idea... I may try that but it's a lot of labor on a 220,000 mile car that can die at any moment. I may just deal wit it


Thanks