Need help diagnosing symptoms

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freak86

New Member
Alright. Here's what's up:
88 crx si
swapped in b16a obd0 pr3
stock b16a

symptoms:
after swap, had o2 sensor "b" code, which is either 2&3, or 1&4 cylinders.
so, I replaced both sensors...figured it couldn't hurt to just do both.
same problem exists now.
problem: after car is warm, usually on long deceleration in-gear, cel comes on for o2 b.
so, then i figured it could have been wiring from the swap.
but now, I have a strange "skipping" sound in my exhuast on cruising, or mostly slight deceleration. it's like it's missing ignition of fuel.
so, i talked to my brother, who's going to wyotech, and he talked to someone, and they said it might be a fuel injector. does this sound legit? i mean, it sounds possible to me, but i'm still somewhat a noob at these things. it makes sense because it's only on one cylinder, which would explain why it's always one o2 cel, "b"....
is there anything else that could cause my symptoms? ie: cat? stock cat with a custom 2.5" exhaust if that is important. the guy that put the exhaust on said that the cat seemed ok at the time.... could a clogged cat do something like this? or is there anything else?
if not, are the fuel injectors serviceable? can i clean them myself?
if not serviceable, what should i look for in injectors if i'm looking at going turbo down the line, and maybe some nitrous. i've already bought a aem fuel rail, so i'm fine with buying new injectors if i NEED them. i just need to know what to look for.
thanks guys.
 
first, check the timing.
second, double and triple check that you ran the o2 wire into the correct ecu pin.
third, get some good fuel injector cleaner (seafoam- pour into gas tank) and run it through, make it a little stronger than can recommends if you want.

no the cat wont have anything to do with it bc the o2's come before it.
 
i'm positive about the o2 wiring.
i didn't think about the timing. that's a good thought.
as for the fuel injector cleaner. i heard that stuff doesn't really work. is there a better way of doing it?
thanks for the input/ideas though. i'll check the timing for sure.
 
some stuff works, some doesnt, thats why i said make it a lil stronger than the can says, run like half a bottle or so with less than a half tank. and then do it the other ways the can says. through a vacuum line. sea foam is good ive used it many times and it fixed my probs.

i think theres a way to take them out and clean them but ive never done it so i couldnt give instructions.
 
update:
if this helps, I took it on a trip to ohio today. here's more details of what's happening:
cruising at 68 mph at 4000 rpm.
slight deceleration, and I do mean slight, causes.....it almost sounds like a semi truck when they use their transmission to slow down. the grinding, instead of smooth, exhaust noise. I really don't know how else to describe it any better. Also, it does bog down the engine at the same time.
the symptoms sometimes show when i slightly decelerate after cruising for a while, and sometimes not immediately into deceleration, but shortly thereafter while still decelerating. so, sometimes, when i'm cruising, i don't notice i'm decelerating, but it happens. and sometimes, it's when i'm intentionally decelerating, and it happens. it stops the symptoms when i fully let off the gas, or when i accelerate. however, if the symptoms are there, and i accelerate slightly, it does not go away. I have to accelerate more intensely, and then it's like a switch flips, and it goes away.
oh, and if i let up all the way on the pedal, and leave it decelerating for too long, it'll throw a cel. but i didn't get one until almost all the way to battle creek, michigan because i never allowed that to happen. but when almost all the way home, i did, and it threw a cel for o2 b again. so, it's pretty consistent. and the other symptoms are as well. i've tried to describe the situation the best i can now. sorry about the long post. my brother and i are going to clean the injectors tommorow. hopefully, that'll fix the problem.
 
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what kind of wire did you use to run the o2 sensor?
some types cant be used bc they get too hot and then you get a burnt wire.
clean the injectors and see what happens,

and damn, used the words "deceleration and acceleration" so much i got lost a couple times.
 
we cleaned the outside of the injectors, and the seals on the intake,etc.... there was some carbon buildup, mainly by the jets on the injectors, and the seals on the intake.
however, the same problem still exists.
my brother seams to think it's a internally shorted injector. does that sound like the most possible problem?
oh, and the o2 wiring is good. i used a guage SLIGHTLY larger than i probably needed to, but that's because i bought the wrong size accidentally. and i don't think that would cause a problem. idk what kind. it's auto wire though.
 
have the coil checked on your dizzy, if you can, dont know if they can do that or not but it could be going bad. try changing the fuel injectors around. take 1 and 4 and swap them to 2 and 3 and vise verse.
then if the injector is to cause, o2a should trip instead of o2b. thats the best way to tell if its that.
try that and see what it does.
 
could the distributor cause the symptoms only when under light decel, and around cruising? my gut's telling me that i should check the plugs/wires, rotor, etc.... i changed the plugs, rotor, cap when i swapped the motor in, but it's a easy check. at the very least, it could also give me a clue also as to what could be causing this.
i'll try looking into the dizzy though too. i didn't realize that could cause my symptoms.
thanks again for the reply.
 
dizzy MAY cause that. im not completly sure.


swap the injectors first and see if you get the same code. thats your best bet.
 
they might be swapped already. when we took them out, we didn't necesarily put them back in the same order. so, if i get the code on "b" again, i'll move them around. thanks though.
 
i swapped 1&4 and 2&3 injectors, and it's still throwing o2b, which is 2&3.
hmmm...
i'm going to pull the spark plugs and see what they look like, and change the valve cover gasket, as i've got some oil up by the plug boots. maybe that'll shed some light on something. could this be caused by fuel pressure, or can i rule that out? thanks for the help man.
*edit* also, could it be a valve?
 
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check your plugs first. see what they look like.
also, check your tps sensor.
it could be something internal, but its best to check all the easy shit first. check ALL of the sensors make sure they read what theyre supposed to. (multimeter)

maybe the gauge wire you used is too big. sometimes the bigger wire is overkill and the signal fades a tiny bit, not much but could be enough to set the light. test the wire right at the o2 sensor and then test it at the ecu. see if you get 2 different readings.
 
I replaced the valve cover gasket/spark plug seals/other seals, and checked the plugs. plugs for 1&4 were significantly covered in carbon on the tips and the immediate threads. 2&3 had significantly less carbon on them. so, there's something behind that obdviously.maybe something triggering the ecu to leaning out the a/f on 2&3. maybe something with the valves/springs, etc.?
checked compression, but the guage was too quick to see, so i'm going to try it again when it's light out
emsmile.gif
. but from what i saw, the compression wasn't extremely off, if at all.
here's another thing. tested the voltage on the o2 sesor wires. o2 for 1&4 is 4.5, and o2 for 2&3 was fluctuating between <1 and 1.6. it was really just all over the place, and i have a auto adjusting multimeter that wouldn't stay anywhere. so, yeah, something's up with the signal from the sensor i would assume. so, it seams it's leaning out on 2&3 for sure.
any ideas? maybe easy ones
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?
i'm gonna check the timing and the tps(once i figure out how, and have the time).
but i honestly don't think it'd be the dizzy. due only to the the fact that it only does it on slight accel/decel/cruising, and not on WOT. it seams something is leaning out 2&3, and that's causing everything. but i'm still open for suggestions, and i'll still try other stuff.
 
What code is coming up on the ECU?? I know you said that something was wrong with the O2 sensor but I'm thinking that it may be due to your vacuum hoses. Poor vacuum pressure can cause a sense of rough running or rough decel or gradual accel.
If your brother goes to Wyotech ask him if you can borrow the sphygmometer for the injectors. Its similar to the thing that doctors use to listen to your heart. This tool can help you identify if there is a clog in any of the injectors.

Maybe there is a short in the 8pin connector on the dizzy. Maybe a bad ECU.
 
you may have a lame o2 sensor. just bc its new dont mean it cant be fucked, take them back and exchange them, then do another reading, if you get the same thing then its obviously something else.
 
Crimson_jay said:
What code is coming up on the ECU?? I know you said that something was wrong with the O2 sensor but I'm thinking that it may be due to your vacuum hoses. Poor vacuum pressure can cause a sense of rough running or rough decel or gradual accel.
If your brother goes to Wyotech ask him if you can borrow the sphygmometer for the injectors. Its similar to the thing that doctors use to listen to your heart. This tool can help you identify if there is a clog in any of the injectors.

Maybe there is a short in the 8pin connector on the dizzy. Maybe a bad ECU.
Click to expand...
code 2 for o2b(2&3 cyl). code only comes on on long decel in gear.
my bro is at wyotech, which is in another state. and he won't be coming home soon.

as for the o2 sensor itself, it did the exact same thing before i replaced it. that's why i replaced it. i guess it's possible that the new o2 is doing the exact same thing, but..... changing those took me a extremely long time, and many scrapes/bruises. they're not exactly in the greatest spot to get a wrench in(had to rent a special o2 socket for it also). if it comes down to being the best option, i'll change it again:(. you've got a point though...
 
guess what.
head gasket.
turns out i'm leaking reasonably small amounts of coolant through the second lower exhaust mani bolt/nut, as well as possibly below the mani on the block. got some exhaust/steam vapors coming out in small amounts. took the heat sheild off(pain), and found a stain from fluid on the mani near the bolt that i mentioned, that ran down the mani. when i started it up, i noticed tiny bubble coming from the slits in the nut on that bolt. also, there was some residual coolant on my block below the mani that i either didn't notice was there before, or wasn't there before.
i'll keep ya posted on if that fixes my problems. i'm putting my money on it, though.
thanks for all your help guys.
 
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