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jcs
09-10-2011, 07:37 PM
ok i have a serious misfire and i have done all the trouble shooting i can possibly think of...well to start with after i had the motor built i installed it like i have many times over,started in the break in miles and on the second day the car completely died while driving found out my alternator nut backed off..after fixing and getting a new battery i fired it up and now my problems begin..very noticable misfire only running on 2 cylinders,i have spark pulled the wire first and there is spark, then pulled the plug and made sure there was spark..so after words i think the worst,and do a compression check 180 across...so now the only thing left i can think of is injectors...i pull the rail and swap the injectors to the other side to see if the problem switches cylinders,and it doesnt same thing on cylinder #1 and 2.i replaced injectors and ecu completely and the prob still persists.the only codes im getting on s300 are vtec spool and IAT..if anyone has any input plz feel free to chime in..thanks ahead of time.


S.N is it possible for the main relay to control only 2 injectors from what i know it controls all 4..

1civic
09-10-2011, 07:40 PM
Change the spark plugs... also you can move the plug wires like you did the injector plugs..

Try everything to move the misfire around, once you see it move than you can replace the part..

injector, or plug, plug wire..

You understand?


EDIT: fixed, lol

jcs
09-10-2011, 08:12 PM
ok well i moved the spark plug wires around 1 to 4 and 2 to 3 and the car will not start at all....any ideas?

Go_Fast
09-10-2011, 08:26 PM
ok well i moved the spark plug wires around 1 to 4 and 2 to 3 and the car will not start at all....any ideas?

maybe its the plugs/harness

1civic
09-10-2011, 08:37 PM
ok well i moved the spark plug wires around 1 to 4 and 2 to 3 and the car will not start at all....any ideas?

no... I didn't mean change the fire order, lol..


Keep the factory firing order but move the plug wires where they reach


OR if you have another set to use then try them.. It's only to exclude them from being bad..

Sorry!!

Mis-fire can be a # of things, from a bad plug, plug wire, injector, ignitor, or even a burnt valve!! you have to go threw and exclude each, one at a time!!

jcs
09-10-2011, 09:11 PM
i used the ngk set from my other h22 and its the same thing...i know this may sound noobish but is it even possible for a dizzy to cripple 2 cylinders,i mean if 2 are sparking shouldnt the other 2..if that makes sense...also i know a bent valve will drop compression but will a burnt one?

jcs
09-10-2011, 09:23 PM
also just swapped dizzys and still the same thing??

CaTcH22
09-11-2011, 09:59 AM
Check to see if the vtec pins are stuck engaged on those two cylinders. Sounds like something mechanical since youve swapped so much around and still havethe same issue.

Cynical 1
09-11-2011, 11:00 AM
valve lash/clearance checked and in spec? it will cause a nasty miss if it is way out...

mechanical timing moved?

otherwise verify spark and fuel at all cylinders...

1civic
09-11-2011, 11:21 AM
I'd go back to the injectors first.. You said you had 180 across the board so don't get to deep in it..

Missing something here, what changed?

I've seen loss of fuel pressure cause an injector mis fire, also seen dirty injectors do the same.. Be sure to keep checking, triple check so you don't over look anything..
Check connections on the injector plugs, and also check the wiring just to be sure..

You will find it's something simple just have to check every option..

YoItsCarlie
09-18-2011, 12:47 PM
oxygen sensor can throw low fuel codes,

start with fuel pressure, with a brand name gauge.
low fuel pressure is clogged line, crap in the tank, fuel pump going bad.
as far as the main relay goes, it will cause a misfire on all cylinders, not just 1 or 2. the relay simply turns on the fuel pump and sends signal to the ecu. solder joins can cause auto tansmisions to go crazy a bit.
once you can say that the injectors are getting proper fuel, move to the wiring. make sure the injecotrs are pulsing.
if not, ohm out the injecot wires(both ground and power from ecu)(ohm between the ecu and injector plug its self, then between the shocktower plug and ecu, shocktower plug to injector plug). check the ground plug on the drivers side.
once you are satisfied with fuel, be sure you are getting proer spark.
Spark trouble shooting (http://techauto.awardspace.com/ignition.html)

jcs
09-18-2011, 01:42 PM
thanks for the help guys it was actually out of time.. :facepalm:

CaTcH22
09-18-2011, 05:18 PM
Now get it over here so I can finish the down pipe and tune it.

jcs
09-18-2011, 05:25 PM
its a coming partner...