hey.
so here is my list of problems. hope someone can help. i tried looking some of them up. heres my story

I have a 91 ef si. and in around august i realize i blew a head gasket. It had a stock d16a6 in it. so while changing the head gasket i put in some arp head bolts, new head gasket a gude camshaft(not really sure which one) a new d16a6 head with a port and valve job. I snapped the stock harmonic balancer by taking a cheater bar and using a stud to stop the harmonic balancer from moving on the frame(bad idea haha). so i just took my car to my friends mechanic and he put a unorthodox harmonic balancer on it and a skunk 2 cam gear.

so here are my problems.
My car is running super rich (i think) I can put my hand to the exhaust and my hand will be covered with black stuff (not sure if its oil or gas). My car wants to die when not given gas( i think it may just be an idle problem which ill try and fix tommorow) and its harder to start

so here are my questions
I have a pretty new ngk o2 sensor. so im not sure if its my sensor, Should I buy a new one?(to prevent it from running rich)
how should i adjust my cam, i am getting a lot of power at the very end of my tac, so im not sure if its adjusted right.
and when i first start it, it seems to be quite bogged down

thanks.
try not to super flame im kinda new to the car scene

 

So your question is? and I'm from tacoma too=]

 

sorry i accidently pressed enter before i was done its edited now.

 

Since you got new cams, I'm guessing thats why your idling kinda rough. If the cams are somewhere equivalent to skunk2 stage 2's and thats your daily driver then I suggest you take it out and replace them with the stock ones because the skunk2 stage 2 will cause too much of an overlap(not sure if thats the right word) during the lower rpms. Overlap is point when the exhaust valve and the intake valve are both opened at the same time, this makes your motor idle rough during the lower rpms, but gives you a good power band at higher rpms.


First try to find out which cams you have exactly, if you can't find out switch the cams back to the stock ones and see if that fixes your running rich problem, idle problem, and the bogged down problem. Remember to torque everything down to specs.

Does the engine sound smooth? Or does it sound like lots of boom boom boom explosions?

 

it is my daily driver sorta. more like my weekend power so i dont really mind the idle problem. the engine seems to be running pretty smooth it sounds really nice no clanks or sputters or nething. my clutch is really messed up, has ~230xxx miles on it. learned how to drive a clutch on it. do you think that might have nething to do with it? thanks man

 

Skunk2 stage2 cams do more than give you a rough idle, it's harsh on an engine, at least an untuned engine. To me it explains most of your problems. If you like going to kent on the weekends, and you use the car as your DD then maybe something equivalent to a skunk2 stage 1 camshaft would be more "right" for you. The clutch has nothing to do with your car running rich, a video or sound of your engine would help some, and would help determine how aggressive your cams are. What did your hand smell like after you took it out?

 

yeah i meant mentioning the clutch towards the idle problem. uhm. im poor and dont have a video or nething haha. but ill see what my car smells like tommorow. ill keep u posted. it really didnt smell like gasoline thomore like a bland smell i believe.

 

do you have the stock cams still?

 

unfortunately the mechanic kept it i think. i heard it might be the piston seals tho?

 

It's the cams, I'm almost 100% sure it is, because these problems came after you changed the gasket, and the cams and a cam thats too aggressive can cause these problems. At least try to trade your cams for something less aggressive with some cash on top on their end.Go ask the mechanic for the stock cams back, if he doesn't want to give it to you then just craigslist or nwsr some.

 

alright is it doing this because its a stock block and its too aggressive for it. because it is a d16 cam. like if i built up the block would it still be running super rich. and if it is too aggrressive cant i just retard the timing?

 

It's doing this because your cams make your engine not like lower rpms.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">because it is a d16 cam.</TD></TR></TABLE>

What are you talking about? are you talking about the cam was made for the d16 or are you talking about its the stock d16 cam...

Heres my little explanation of what the cams do and how it works.

As you should know your cam has lobes which controls how long the valves are opened for the intake and exhaust flow. Since I have no idea what your cams are, I'm just going to call them skunk2 stage 2's, since yours are very aggressive and so are theirs. As you know, or should know, skunk2 stage 2 has a very high powerband, which means the lobes are bigger, which means the valves are opened longer than normal(theres your reason why your getting a lot of high end power). At lower rpms the valves are opened too long thus making it idle roughly(there goes your idle problem), and since I'm pretty sure no one was revving the car up to 5k when you had your hand in the exhaust that some gas may not have ignited which means some gas might flow back to the tailpipe(not 100% sure on the gas info but I'm pretty confident about it), there goes your "running super rich" problem.

I'm not sure about your bogging problem, but it can also be because the cams are too aggressive, and your not getting enough power from the combustion step.

Hope you learned something.

If anything is wrong, please correct me. I don't want to go around thinking my answer is right when it's not.

 

hey man
i really do appreciate your help. were you at the nwsr meet? neways. your answer does make sense to me. i realize they are very aggressive cams (the box just said d16 skunk 2 cam) i dont really mind the idle issue as i think i may pick up another ef as a daily driver. and i think i want to build up this engine. will running really rich affect my engine life besides like destroying the cat? because i plan on running a turbo in the near future and would like to build this engine. thanks for you help again. you really are informing me

 

I say switch the cams back to stock ones when you gotta take emissions, and take the cat off after your done with emissions. No I didn't go to any of the nwsr meets, I'm also pretty new to the honda scene. If you pick up another ef for a dd and want to keep this car as your weekend power thats good. Running on lower rpms with those cams will waste power because not all of the combustion force is being used to push the piston back down but at higher rpms, the valves are overlapped for a shorter time, therefore your getting more air in the cylinder and your not losing as much as what you would lose at lower rpms, but you gain more power than stock cams.




Modified by Hanmin at 4:20 PM 10/24/2007