I’m going to try pulling that vacuum house off and see what happens. How does it effect the mpg?
I had that code on my civic and it was the 02 sensor. Its probably not a vacuum leak.
lean means not enough fuel for the air coming in, you need to add fuel to make it run right. adding fuel logicly will reduce mpg… albeit adding enough fuel to keep the trims in check to not toss a code will be marginal at best… so its not like your going to go from 31mph to 13 mpg… but never the less fueling it properly is a nessesity not an option for mpg expectiations.
Pulling the vac line off the regulator is just allowing the regulator to NOT open up and relieve fuel pressure at low engine load (high vac conditions) as in idle or partial throttle… therefore all its doing is making (for example) the fuel pressure at the injectors go from 20psi under low load/idle to say 43psi (3bar which most regulators are)… staticly across the entire rev/load range severly riching up the afr when the ecu/motor doesnt really want/need it. Unless the ecu is expecting a static 43psi or whatever durring all engine conditions this should not be done. (that regulator is just a simple spring and diaphram. the vac signal sucks against the spring pressure to unseat the diaphram to piss fuel past it and into the return line back to the tank. aka thats how fuel pressure is regulated)
The bottom line is you need to find out the “why” its tripping the lean condition. then work backwards to find the cause of that “why”. For all you know you could have one lazy injector thats leaning out one cylinder enough to throw off the ARF signal out the exhaust manifold to throw the cel. To check that pull all 4 plugs and read the electrode’s color to figure that example out.
exactly. the signal for the ecu is coming from that o2. the motor could be running 100% perfect AFR wise but if the sensor is getting/sending a shitty signal its falsely kicking a code. which is why another known good wide band should be used to verify it, why pulling a data stream from the ecu is needed, etc.
Kk your a knowledgeable dude. Thanks for all the input. I have been poking around and I’m not coming up with much. I found a random plug that I can’t seem to find where it should plug into. Not sure if it’s swap related. I have another o2 sensor I’m going to put in and see if that solves the problem. I also have a96 full running Integra in my driveway so I guess I can use that to find where that plug should go
look up a wiring diagram for it. The engine harness diagram should lable the wire colors and show you what it goes to. Good diagrams like ones out of all data have a legend with the plug faces too that can help. I would look for you but i no longer have my subscription to all data becasue I dont do repair work anymore.
I wasnt trying to be a dick or a know it all up there btw, infact i will admit i know very little about the honda platforms specificly, but the troubleshooting and such is a universal skill to an extent. I def dont know everything and i make mistakes sometimes like everyone, im just being blunt so you dont waste a ton of time thats all.
If you dont already know how, google spark plug reading. Basicly you pull a plug and look at the end, if its black sooty its rich, if its white as a ghost its lean, if its brown/tan its right where it should be. thats a ball park, some people can read a plug and tell you all kinds of info even if your headgasket is starting to blow by, pinging, etc. Its a very usefull skill. My point is, I would pull all 4 plugs, they should look the same. If you have an odd ball you can troubleshoot that cylinder itself (plug, coil, wire, injector, compression, valves, intake port, exhaust port, etc). But atleast pull the plugs and see what they look like.
Honda guys, whats the swing on those ecu’s +/- for fuel correction before it pops a lean/rich condition code?
I haven’t had time to look at the car yet but it’s getting terrible gas mileage. I’m at 100 miles and I have used a half of a tank with no hammering at all
This sounds like an awful setup. I’m sorry , just feel like you just got fucked over bad. Any way to contact the original owner to figure out more about the car ? Or at least the person that did the work ?
Why the hell is this under projects?
Should of been under tech.
Speaking from experience? :crackup
haha exactly !
I still like the car. And the bad gas mileage May be because of the vacuum house I pulled off the regulator
or its from a bad o2… if your o2 is telling the ecu to add fuel when it doesnt need it bang thats your bad mpg problem.
then if you cel is on for a lean condition that could be fixed by the same o2 sensor. once the o2 craps out it will not read correctly. so a bad sensor could have your engine throwing in too much fuel and it will still think its running lean.
newer cars use the o2 to fatten the tables or lean them out. depends on the reading the o2 sends to the ecu
Just to let you know you cant socket obd2 ecus and have them pass inspection and they are also not flash tune-able SDP is right for right now a quick fix unplug the vac hose to the fpr just to see if it maintains the cel or clears it if it goes away buy an adjustable fuel pressure regulator that will be your fix if the cel continues look closer at bank 1 O2 sensor 1 thats the one closest to the motor its the one that controls the fuel table it maybe malfunctioning to where it wont throw a code but the voltage values are close to out of range other things that influence fuel air intake temp sensor check for vac leak or broken wires thats just a couple ideas to help
Thanks guys. I’m going to try the o2 sensor. I have a spare from a teg I had a few years ago.
use a . in between and some spaces and i will read this
tell my friends in cali with a aem fic obd2 turbo civic that passes inspection and smog.
i know a guy in ny that modified a k pro to work on a b series obd2 turbo. passes everytime
I don’t need to tell your friends in California anything.This is New York and our inspections don’t involve 5 gas analyzers and dyno time. They are based on factory pcm readiness to pre-test and post-test emission components on vehicles.
“Just to let you know you cant socket obd2 ecus and have them pass inspection”
thats what you said. i know you can do this. just takes more time and money than switching to obd1.
i have tuned obd0, obd1 and obd2 hondas