STP

OK-this one has me. Started the car this morning and CEL comes on. (never happened before) Driving home from work and it starts blinking and I can feel the rough idle. Went straight to Autozone for the OBDII and got:
P1298 - Manufacturer Control Fuel Air Metering
P0303 - Cyl #3 misfire
P0304 - Cyl #4 misfire
P0300 - Random Misfire
P1399 - Manufacturer Control Ignition System or Misfire
I have 40k on new timing belt, plugs, wire the works. Just wondering if anyone else has seen this and if they can help.
It sure would be appreciated.

lazlong

Sound like the distributor.

STP

Nope - not the distributor.
Compression checks are good.
New distributor, new plugs, new wires.
Valves have been adjusted - but a couple are a little tight but should be OK.
Replaced the ELD sensor.
Anyone have any ideas - I hate wasting money this way.

eghatch4sale

Usualy those codes EQUAL bad valve

STP

Is there a way to verify that before spending the money for a valve job?
I would have thought it would have failed the compression test.

fast2camciv

i would think it should show up on a compression test (it did on mine...burnt valve = 30psi)
a leak down test will give you confirmation on the health of the valves.

sounds like a burnt valve to me. i had all the same symptoms. but could be distributor related as well. and ignition spark tester should clue you in to any dizzy related issues.

honda fossil

when it comes to valve lash tight is never good as it can change the profile of the cam make the valves open and close sooner or later then normal

DumpdEJ6

This is happening to my friends CRV as well. I replaced his timing belt after it broke, we thought we were up sh*t creek but everything looked fine, there was slight carbon buildup on his pistons and it was undisturbed, meaning the valve must never have contacted the piston.

It ran just fine for a few months, then the CEL came on and started blinking. Cylinder #4 is misfiring and engine speed isn't effected by removing the #4 spark plug wire.

I have spark at the plug, injector tested fine, timing is spot on. Any clues as to what this is? I don't see how it could be a bent valve since there was never any contact.

fast2camciv

THIS.

mine did the same thing. did a compression test and cylinder had 30psi...cyl 3 had a pencil eraser sized hole in the valve. but yea, same symptoms...misfire codes, and pulling #3 wire made no difference in RPM's. <--- classic sign of a dead hole.

DumpdEJ6

I just did a compression test as well, 0 psi in cylinder #4. Is that bad? lol

Pulling the head off now. Can't wait to see what this valve looks like haha.

DumpdEJ6

Ok, just to follow up, pulled the head and sure enough, one valve has a piece broken off. I'll put pics up tomorrow just for laughs. I didn't adjust the valve lash after putting the engine back together from the timing belt job. Why do I always have to learn the hard way? lol