CarTalk.com Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

Misfire 2.3 vtec

Hi,I recently purchased a 2002 Honda accord ex 2.3 vtec,I have replaced cap,rotor,plugs,wires,plugs and wires are ngk,it still has a misfire,or random misfire,the cel flashes until you hold it at one speed,then cel is solid,until you give or take fuel,I also replaced pcv valve,just looking for a direction

First. don’t drive the car with a flashing Check Engine light. Damage to the engine/catalytic converter(s) can occur.

Other things that cause a misfire are, a bad fuel injector or valves out of adjustment.

Tester

Has anything changed, better or worse, with the things you have done so far?

What do you know about the timing belt replacement? The crankshaft and camshaft can be out of synch if that is not done right. I would remove the top of the timing belt cover and have a look.

1 Like

On second thought: remove the valve cover to see about crankshaft/camshaft in synch. Once that is OK, check valve adjustment. Every time I’ve done that on my 1999 Civic some had gone a bit of adjustment.

Everything you all have mentioned is ok,misses at idle,cel flashes unless I can get the rpms steady,then cel stays solid,the only code I get is random misfire,could a plugged vvt solenoid cause it ? It is running a wee bit better

The misfire being worse at idle than at a higher speed might be a clue. For example if there was an air leak allowing unmetered air into the engine, that would produce more grief to the engine at idle than at speed. At speed there’s already a lot of air going into the engine, so a small add’l leak isn’t noticed as much.

Does it feel like it is actually misfiring when you drive it? Isn’t running smoothly? Sort of stutters on acceleration? If so I’d probably start off w/a fuel trim measurement to see if there’s any indication of a air/fuel mixture problem going on.

Common causes of misfires occurring across all the cylinders rather than just one or two

  • MAF sensor
  • air/fuel mixture problem
  • fuel pressure not to spec
  • bad gasoline
  • worn engine, poor compression
  • battery/igniter problem
  • crank/cam position sensor problem
  • plugged exhaust system

Could be a vvt solenoid, but that’s usually accompanied with a diagnostic code. The computer can usually tell if the vvt solenoid isn’t doing its thing.

1 Like

Ok,I will check them out, I will respond back in a few days,its January in maine,need garage with heat lol

Checked compression #1 is 0,the rest are within specs,leaning toward blown headgasket

Actually, that sounds more like a valvetrain problem

Perhaps a burnt valve

Have you had the codes read? 0 psi in #1 is a BAD sign.

Codes are p0300,p0301 and p0303

Concur w/ @db4690 … more likely some sort of valve problem. OP should give themselves a chance to be lucky by having a shop remove the valve cover and doing a visual inspection of the valve train. Could be a broken valve spring for example, which can possibly be replaced w/out removing the head.

1 Like

Ok george,I will check it out,I’m a shade tree mechanic,cant afford a real one lol,I will get back,thanks for all your help