Replaced Intake Pipe

[R-SPEC]

i replaced the stock intake pipe on my r34 gtt today with a metal one (non stainless steel)

now before you ask, yes my bov is blocked.

now there were 2 vacuum hoses going into the intake pipe, 1 was the bov plumback and the other goes to the engine/head.

i connected the 1 coming from the engine to the intake pipe but cancelled the plumback system as theres no use for it since bov is blocked.

car now comes on boost slower than before and stalls when braking hard/suddenly lifting foot off throttle.

i dont get why it stalls now as the bov was blocked before i replaced the intake pipe.

can anyone help out?

also, if you cant help then dont post. im not interested in any anti-flutter crap.

thank you

Edited June 13, 2008 by R-SPEC

[rev210]

Sounds like you have a vaume leak, hopefully thats all. check all the connections Including ones like the intercooler pipes.

I assume you have an aftermarket ecu or something to account for the decelleration fuel values if stock ecu?

[DECIM8]

did you block off the pipe which comes off the bov? You stuck a bottle top in it or somthing and clamped it down?

Id say a leak.. It could also be related to the tune but its deff to much unmeasured air getting in or comp surge from the turbo measuring the intake air twice.

Dual measurement will make it run like shit as it injects to much fuel.

Edited June 13, 2008 by DECIM8

[Bunta]

have you got pics of the pipe, im thinking it is too short and you are getting inlet reversion that is screwing with your AFM

[Guilt-Toy]

go to your local servo or corner store.

Buy a bottle of coke.

Drink it.

Use the lid on the pipe that plumbs back to the intake and clamp it (NOT TOO HARD)

Run around the block 5 times to burn off the calories from the coke.

If you use diet coke or coke zero then thats cheating.

[RBwhatever]

go to your local servo or corner store.

Buy a bottle of coke.

Drink it.

Use the lid on the pipe that plumbs back to the intake and clamp it (NOT TOO HARD)

Run around the block 5 times to burn off the calories from the coke.

If you use diet coke or coke zero then thats cheating.

haha but the chemical sweetners will probably kill you quicker anyway. Whoops majorly off topic

[Guilt-Toy]

WHAT!!! ?? You drive a commodore?

haha but the chemical sweetners will probably kill you quicker anyway. Whoops majorly off topic

[R-SPEC]

yeah the pipe is shorter than the stock 1

i got rid of the plumback piping thing.

after i made this thread what i did was i bought some vacuum hose, ran it from the engine to the intake pipe and with that hose i tee'd off a 2nd hose wich i connected to the bov plumback outlet.

as a result car is running like normal but i'm still getting the stalling problem only now its not as bad as before i did this. although it now even stalls if i give it a 2-4k rev on idle...

car has stock ecu, well mines vx rom thingy...

it is running rich as i get loud pops from the exhaust.

btw its running no pod/filter as the way the pipe sits it doesnt alow a pod to fit. will get that sorted though dont wanna run no filter for long..

thanks

[rev210]

yeah the pipe is shorter than the stock 1

i got rid of the plumback piping thing.

after i made this thread what i did was i bought some vacuum hose, ran it from the engine to the intake pipe and with that hose i tee'd off a 2nd hose wich i connected to the bov plumback outlet.

as a result car is running like normal but i'm still getting the stalling problem only now its not as bad as before i did this. although it now even stalls if i give it a 2-4k rev on idle...

car has stock ecu, well mines vx rom thingy...

it is running rich as i get loud pops from the exhaust.

btw its running no pod/filter as the way the pipe sits it doesnt alow a pod to fit. will get that sorted though dont wanna run no filter for long..

thanks

The factory ecu is not getting the recycled air from the bov on decelleration, so you get overfueling. Can cause stalling and other issues.

Sounds like removing the factory BOV hasn't been a good move for you so far.

I'm sure you don't hate your car but, not running an air filter on top of everything else isn't good for things.

[RBwhatever]

WHAT!!! ?? You drive a commodore?

Lol heck no, I considered it once though.

[femno]

Well if you only changed a couple of things then it has to be one of them.

The 'bought some vacuum hose, ran it from the engine to the intake pipe and with that hose i tee'd off a 2nd hose wich i connected to the bov plumback outlet' sounds a bit sketchy....

[R-SPEC]

The factory ecu is not getting the recycled air from the bov on decelleration, so you get overfueling. Can cause stalling and other issues.

Sounds like removing the factory BOV hasn't been a good move for you so far.

I'm sure you don't hate your car but, not running an air filter on top of everything else isn't good for things.

yeah but i know of people with r33's who have done the exact same thing and they have no issues at all. except for ofcourse the car running a little rich.

i dont hate my car lol like i said its just temporary until i get it sorted

could the problem be with the afm itself? it has been taken out/put back in HEAPS of times

Well if you only changed a couple of things then it has to be one of them.

The 'bought some vacuum hose, ran it from the engine to the intake pipe and with that hose i tee'd off a 2nd hose wich i connected to the bov plumback outlet' sounds a bit sketchy....

ive checked everything its all nice and tight.

lol wat you mean bit sketchy? both the plumback and the other line run to the intake pipe, and since i ruined the plumback piping i thought wats the difference i'll just run a hose (same size as original) to the intake pipe and tee off another bit of hose to the bov since both the original ones go to the same place...

ive noticed that car now on idle on cold starts it feels like it cuts out/stutters

[rev210]

without an air filter you stand 100% better chance of rooting the AFM. Don't drive around without one, it's very silly.

To top off the fact that the 'dose pipe' isn't nice to the turbo you are letting it suck in dirt too.

[paulr33]

try it with a std ecu? maybe mines have put some stupid stuff in there - who knows

[nizmonut]

hmmm, when you block the recerc valve, the boost that would normally bypass back into the inlet pipe also helps to balance the pressure drop stopping bacl spool,

the term back spool doesnt actually mean your turbo stops and starts going backward, the sound you hear from a backspooling turbocharger is the pressurized air between the throttle body and the turbo coming to a sudden halt having no where to go the turbo is forced to slow down and as it does the air starts creeping back out the way it came in, the shh shh shh shh you hear is the air pulsing backward then forward as the impeller balances itself back to a constant speed.

while doing this the air between the turbo charger and the air flow meter is also moving backward and forward as two particles cant occupy the same space therefore creating a knock on effect back to the next lowest air pressure point which is inside the air box/ or inside the pod filter,

the air flow meter measures air flow...not the direction it is going in, so if the air is pulsing back and forward for example four times or "shh shh shh shh" the air flow meter is measuring that air four times, so obviously the fuel load is going to be four times what it should be....

this is what causes the engine to stall/cough and splutter....

this is also why, when you dump the air back to the atmosphere on a standard skyline system it will also stall/cough splutter as the ecu has already allocated a certain amount of fuel for the already measured air,

dumping that air causes richness, dumping 14 pounds per sqaure inch of air for example will likley cause an engine using a recirculated system to stall.

[R-SPEC]

ok so how do i fix that problem? ^^^ without returning everything as it was standard...

car seems to be slowly fixing itself the more i drive it

without an air filter you stand 100% better chance of rooting the AFM. Don't drive around without one, it's very silly.

To top off the fact that the 'dose pipe' isn't nice to the turbo you are letting it suck in dirt too.

its not a "dose pipe" and it has nothing to do with it. the standard rubber pipe sucks itself close and it started to annoy me so i wanted to change it.

try it with a std ecu? maybe mines have put some stupid stuff in there - who knows

thats too technical for me all i know about the ecu is that its removed speed/rev limiter etc

[justin911]

howd you know the rubber pipe was closing by its self rimona ?