ok. so i have a 93 coupe. with 2001 gsr b18c in it. i am running 7psi. it has run fine the last few weeks since i got the car. today i was driving and the gears got realy sticky, wouldnt wanna go in any gears and i have to force it in. grinds sometimes. and when i hit boost the a/f gauge goes to lean. aka not good. and it boggs out in full throttle boost. i turned the car off let it sit for 45 min or so..in 12 degree temp. start it up. bam runs fine. but once i got back out doing 60 on road. gears got sticky and boost was bogging lean again. could it be a vac line? i have a fmu and vafc2...

also, like when i let the car sit over night or for few hours. ill get in and my clutch peddal will be all the way to the floor. so ill pull it up and it will be fine? its a stage 1 clutch. fluid is full.

any answeres?
thanks

 

Hi man,

i think can be vac line of fmu of fuel pump on holiday....Sticky gear u mean hard to move shifter?
Orings in clutch pump/line can be damaged, without oil leak but with pressure lost in circuit and ur pressure plate does not work perfectly and clutch does not opens.
check for it.
Also change transmission oil and try.

 

I found a vac line from the fmu to the intake mani thats pinched. But it ran fine before. I also found a soft vac line that pinches itself when the car revs up. I think it may be that line

 

ok its a stock b18c not built. running 7psi. has fmu and vafc2. do anyone know what the air/fuel ratio on the vafc2 should be? it only leans out when boost hits. but it was running fine before. i think my bro might have messed with the vafc tho. may have changed the a/f settings. i realy dont know how to work the vafc. if anyone can tell me step by step how to change the a/f or whatever els may need to be changed on it to the correct numbers. that would be great. i dont wanna hurt my new car!

 

anybody?!?!?!? i need to fix this before tonight!

 

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

 

you need a wideband
tune for 12:1

 

also your clutch master might be leaking
look for fluid under by the pedal

 

ok thanks. so i can not fix the problem by settings on my vafc2? because it ran fine last week. boost was smooth, no bogging. then out of nowhere it runs like a turd when boost spools. leans out

 

you really need to get some real engine management you using ten your old technology and expecting it to run perfect.

 

i know, i agree. thats how i got the car. i will probly take the charge piping off and not run boost till i can get it tuned again ( eliminate fmu and vafc2) i was just wondering if i could get it back running right till i got the money for another tune.

 

Ditch the fmu and vafc and get ecu tune and im pretty sure your problem will be solved

 

could it also be the injectors or fuel pump? cuz it was fine before. maybe not getting enough gas to motor=runs lean?

 

could be setting with wide throtle and narow thortle on vafc?

 

do you have a wide band?

 

i have no clue, this is my first boosted car and i dont know much about it. maybe pics could help idk...

 

How many fuel psi are u running. U need wideband to monitor af ratio and to check replace vacum/ boost reference lines. Also as i said check the fuel pump maybe she is going on holiday....
I it goes lean only under boost means not enogh fuel and is due from malfunction pump, not correct map and fmu not working correctly.
Check.

 

why don't u fix directly fpr on fuel rail maybe is the hose that bends...Some problems on it?

 

ok, so when i got the car it had this pinched vac line. it was so short it was pinched. but ran fine so i left it. after it started running like ***, i though maybe its that vac line. so i made it longer so it would not be pinched...(the line runs from fmu to intake mani)....when it is not pinched in runs 40psi fuel pres. when it is pinched (like it was when i got it) it runs a lil over 50psi fuel pres.?? ...so i went out and pinched it with a zip tie, ran it up to 50psi drove it, but it ran the same? so thats not it? i am so lons in this mess =(

 

could my timing have jumped off a bit not letting fuel into the motor under boost? im sorry for all the questions. i just realy want my car to run right again and dont realy have the money to take it anywhere. i just seeing if there anything I can do to fix it. if not i guess ill have to drive it few more weeks and hope it dont mess anything up till i get money for tune......

 

you fix that problem ? if not change your fuel fiulter i read on another thread on honda tech a guy having the same issues with the bogging in boost , try the fuel filter or rev the car with your hand and watch the fuel pressure gauge if its drops then you know there is a plug somewhere and its lacking fuel ? if thats not the issue then you may need to consider aretune on your vafc or maybe consider taking it to a meet and talking to people that have a little more knowledge , hope the best for you bud

 

Like you said earlier...Do you know if someone messed with your VAFC? If they went in there and messed around with the settings that will cause you to run lean. You need to get a wideband to ensure you are able to monitor your a/f. Your best bet would be to remove the turbo and put a header on there because just pulling off a charge pipe will still make the turbo spool but you will end up overspooling the turbo and possibly causing damage to it. Just my .02 cents.