b16a misfire help?

[civichatch982]

I'd really appriciate it if you guys could help me I'm on my last thread on this engine. I recently installed a b16a siR-II engine in my 96 hatch and everythings running great except that there's a light misfire in the engine. Its not a heavy one where a single piston is just completely missing but where its just not running quite right, hopefully you can understand what i just said.

Anyway here are the things I can rule out and i know arn't the case. I'm fairly sure its not spark unless overall its just not sparking good enough, but I just replaced the wires, distributer cap and rotor, and I have bosch platnum 4's in there. Timing is on, and the engine is holding compression and is pushing full compression just fine , so that rules out a number of things (bad seals etc.), resistance is fine for the injectores and all 4 are running fine. Fuel pressure is at around 47 psi with the fuel pressure reg. vacuum line off and 38 psi. with it on.

I have intake and full exhaust (headers, high flow cat, and tanabe racing medallion cat back exhaust)

Most people are probably just going ot look at this thread and not have a clue, but say anything please because I need any idea or hint I can get thanks.

[civichatch982]

its not burning oil at all either pretty clean over all, forgot to put that in there

[honda4u]

are u positive that the timing is dead on?

[95whitehb]

it seems like the timing isnt quite right, mite wanna try advancing it some then see how it goes, mite lose a little hp. then retard it slowly as time goes by and see what happens when u do that.
-that was happening to my buddy and he up-ed the octane level and that helped. thou he had a dif. engine set up than u

[civichatch982]

thanks man I'll look into that, maybe its time for some adjustable cam gears haha. yea I have 93 octane in it right now so it will hopefully pass emmissions (however you spell it)

[civichatch982]

I'm pretty sure timings on, we took a timing gun to it and the little red dot and the little white dot are where they should be .. it does sound like a timing problem. I think I'm going to be taking it into honda today or tomorrow and see if they'll do a diagnostics check or possibly track down a buddy witha p30 ecu and swap them to see if my ecu is bad.

Thanks guys I appriciate the feed back let me know if you have any other ideas

[civichatch982]

yea .. so I advanced the timeing .. theres no change .. I'm lost

[civickiller]

could be the coil. check the spark is it strong or weak ?

[sohcfreak97]

if coil is good, try using factor ngk plugs, platinum plugs were originally designed for waste spark coil packs and cop.

[civichatch982]

yea spark is good I already have the factory ngk plugs in there, i think its down to a bad ecu or a valve.

[sohcfreak97]

Compression Test? Get Noid Lights And Check Each Injector

[Schister66]

Did you run a gasoline with too low of an octane rating? Are you sure the timing is correct? How old is the engine? If it is an older engine that used to burn oil, there will be carbon build up on the piston head that will stay incandescent and cause pre-ignition. I would say to re-check the timing...does the engine have a knock sensor built into the computer (resets timing when a cylinder fires too early). I would also suggest running a higher octane gasoline and see where that gets you. Post some results.

[civichatch982]

yea this car injests only 93 octane .. I was thinking around the same lines for the carbon deposits on the piston head .. thats all I could think of .. but the engine doesnt seem to burn alot of oil .. a couple other people have said a bad valve could cause it too but timeing is dead on ... so I'm still at a loss ..

[5gcivic]

Originally Posted by civichatch982

yea this car injests only 93 octane .. I was thinking around the same lines for the carbon deposits on the piston head .. thats all I could think of .. but the engine doesnt seem to burn alot of oil .. a couple other people have said a bad valve could cause it too but timeing is dead on ... so I'm still at a loss ..

Do a compression test, that will tell you in less than 15 min if you have a bad valve or something else going on inside the engine without tearing it apart.