99 civic? ever tune it up, or run the cam belt fore ever?
you do now, ignoring the bent, ends in bent valves, right?
which engine option, cylinder count and displacment. USA 1.6L? I-4?
misfiring. ever tune it up this decade? or 60k miles? with cam belt.
1399 is misfire (let me guess, the CEL flashes )
do not skip the belt if due, or you will lunch the engine.
420 is: (ID IGNORE THIS, till the MISFIRE ENDS !!!)
- Three way catalyst converter Bank 1
- Exhaust tube
- Intake air leaks
- Fuel injectors may be faulty
- Fuel injector leaks
- Spark plugs may be faulty
- Improper ignition timing
- Engine Control Module (ECM)
(the bar room answer for 420 is, the CAT is weak, )
the autoshop class>? ASE.. if the cat is or was tortured (misfire)
then fix that first and pray the cat bakes dry and passes 42x codes
if bake many dry, and 420s cleared.
what happens is you overload the CAT with raw fuel, ignore it.
the CEL flashing (USA) means you are KILLING THE CAT.
now we cover, misfire
there are huge possibles.
in a big shop we connect 5 gas to tail and start there .
in a lesser shop, plenty. we check closed loop at idle
if not in closed loop at idle, we fix that first. (easy ,car is parked)
(later closed loop at 40mph light flat cruise, steady right foot) no hills.
Bad engine, bent a valve> do to ignoring the belt. got vacuum bounce?
bad injection rates, or injectors clogged ,dead or weak or leaking.
me, i watch pendings to see of P0301 , to P030x (x is cylinder num)
if the scan tools shows any misfire codes, i do a leak down
on the cylinder that misfires, 300s is random.
lots of ways, EGR stuck open
AFR runing lean, scan too sees that...
AFR stuck rich, same.
the best order is this. (no clues with extra DTCS
compression test. and leak down. if smart.
last fueling, rates, (fails closed loop at idle spark good , engine good.
i do the the injector leak down tests. and balance,
i also do the cAT melted test. cat back pressure test
less that 2psi at 2500rpm.
Dec 31, 2013 |
1999 Honda Civic