Terrible Engine Start Misfiring! Please help :-(

[Bns2000]

My 02 EP3 is having some bad misfiring what I start up the car. But this is only if that car has no run for about 2hrs or so. Also the longer it sits the harder it is to start. Now after I do get it to start and gets past the 1k rpm it runs perfect after that even when it goes under the 1k to idle. So anyone know what might cause such a problem?

Engine Codes
P1166
P1167
P0141
(The top 3 I think are because the last owner of the car removed the Catalytic Converter)
P0300
P0301
P0302
P0303

[FoReVaPmP]

if the car is misfiring, why are you driving it and going over 1k rpm???....


you might want to check the spark plugs / type of "Oil" / gas / ..... it also sounds like "maybe" a bent valve....

[talonXracer]

P1166, P1167 and P0141 have nothing to do with the cat convertor, those codes are for the heater section of the o2 sensors, both primary and secondary. Check fuses and verify the connectors under the car are properly connected.

The majority of the time a misfire is caused by either a vacuum leak or bent valves. A overly rich condition can also cause misfires. You need to grab one of those small propane bottles and start the engine and open the propane and aim it at potential vacuum leak areas and if there is a rpm change you found the leak.

[Bns2000]

Well I have looked at all the fuses and I have looked at the spark plugs and they are all good. Lol now the car won't even start. It tries every one and a while but not all the way.

Sent from my SAMSUNG-SGH-I997 using Tapatalk

[USAF EP3]

Maybe talon was right and you DID bend or had bent valves. That sucks man.

Well, now go swap a K24A1! Lol.

[Ba82Ep3]

Pop the valve cover off... look for a broken valve spring retainer/dropped valve. Also, check your timing while youre in there...

[Bns2000]

I looked at the O2 sensor and it was all pluged in and the wire.all looked good. I think I am just going to take it to the Honda dealer next to me as I can not figure this out for the life of me.

Sent from my SAMSUNG-SGH-I997 using Tapatalk