Alright so I’ve always been the Mr.Fixit guy for all things cars, computers, phones, etc. This particular problem seriously has me stumped and I’m wondering what I may be overlooking and If one of you can help me out.

I have a 2000 Honda CR-V with about 143k miles on her. About 2 weeks ago, CEL pops on and I’m noticing the engine shake, rough idle, and gets bogged down in lower gears so I have to floor it for it to go and it corrects itself.
popped BlueDriver scanner on and it’s pulling a P0303 engine misfire code.

My first instinct was to check electrical, so I went to the spark plugs to see what’s up. Changed them up and they seemed fine. No oil in spark plug well, no excess corrosion on any singular one, etc. Then thought, maybe distributer cap. Pull each spark plug wire out and engine performance downgraded as expected. Next up was a compression test. Pulled 65psi across all of them. Thought that was quite low so I thought to myself that maybe the timing belt slipped a tooth or two so I changed the timing belt and also did the valve cover gasket while I was at it. STILL nothing changed.

I did an intake and exhaust valve adjustment making sure each were gapped appropriately and even pulled each stem up to make sure they weren’t bent. Valve cover back on and still nothing changes. Got to thinking that since it’s getting bogged down, maybe it’s a problem on the fuel side so I changed over the fuel rail and all four fuel injectors. Ran great at start with higher rpms, then once settled, the misfire started up again and in the same way. I checked with a long stem flat head to see if the injectors were all going off in accordance and no problems there either. Seriously don’t know what else to do besides a kerosene soaked rag in the gas cap at this point. Any suggestions would be greatly appreciated.

Also to note, the previous owner did a cat delete and the place where flex pipe and cat converter would be is a piece of pipe welded in...idk if that would pertain to this particular issue, but I felt it necessary to mention since I’m not sure that if without the flex pipe “give” it could jostle something loose on exhaust side.

Thanks,
Matt

 

Also, no blue or white smoke indicating head gasket and when I do floor it to get past that bog down session in lower rpm, CEL is flashing a “Danger Will Robinson!”..yeah I’m at a loss here

 

CRV / B20's are finicky regarding valve lash adjustment. The design has weaknesses, which allows for continued pressure on the valves to be "pushed" into their seats over time, making it difficult to maintain the proper gap on lash. One solution for extreme cases is to remove the rockers unscrew and remove and ball/thread shaft, and file a mm or two off the back side of the rocker, allowing for it to drop down slightly farther to maintain lash gap.

If there is not enough lash gap allowance, particularly with the exhaust, can end up causing burned valves. This usually manifests with poor idle, lack of power, missing, and multiple codes, mainly 300's or 1399 which is Honda's all purpose code for multiple cyl. missfiring. In this case a valve replacement / grind is the remedy.

 

Are the internal leads in the distributor cap made of aluminum or brass?
If they are aluminum, then it oxidizes from being blasted with the spark under high temperature, whereas Al2O3 aluminum oxide is one of the best insulators. It causes rough idle and misfires.
I do not know what design of the distributor rotor Honda used, but if it is anything like Nissan's rotor where the contact with the cap leads is made via a carbon fiber PCB, then the metal layer in the PCB also oxidizes and burns into the carbon fiber, increasing the gap from the rotor to the cap. Check that out.

 

Honda, being a great engine maker, has had its moments of stupidness...perfect example, the older dizzy caps..No.1 culprit for sluggish performance etc. the Cap. not the internal leads, but the weak crappy spring under the center pin, which corrodes, and weakens to the point where it doesn't put enough pressure on the carbon pin to contact the rotor center. In the past, i've actually taken a bic ball point pen spring and used it, ended up working far better. Also the coil spring can do the same. No.2 culprit: poor grounding due to crappy bolt steel that corrodes in aluminum. The 96 & new civics are a perfect example. the entire electrical ground system relys on 1 10mm bolt connecting battery ground to body. I always double ground the engine / ecu with german made bolts etc. No.3 Culprit crappy main relay ..which usually needs resoldering.

 

Cel still pertaining to cyl 3?
try testing the plug wires?
bent or burnt valves? How can you verify this from above?

 

three ways to know for sure if you have a burnt valve. (bent valves only happen if your timing belt breaks).
1. Compression test
2. Use mini cam down plug hole to look inside.
3. remove exhaust manifold and you can see the back side of the exhaust valves, and you should be able to see if one if missing a chunk .

good luck!