littleblue

Its been about 10k miles since I rebuilt and tuned my engine, I have noticed idle is being strange at certain temps, running a bit rich 9-10ish with throttle, 12-13 idle. So how often should I retune?

locash

Uh, unless something changed with the setup, it shouldn't need retuning after 10k miles..

teg racer 877

i went 60k without retune

SIXTY-1HATCH

You don't re-tune just b/c you have some mileage. You re-tune b/c something is not running right, or you have made some upgrades to the motor that knocked off the tune somehow.

If it's running that rich, that have someone touch it up. Just remember winter time the car is going to run leaner, and in summer will run richer. It depends on what the temps were when you got tuned originally, etc....

littleblue

I figured as much, It's about 70 out right now I was sitting outside my house with the car to 180, the idle was going up and down, but not as if there is a vacuum leak, my vac is 21ish. It's the strangest thing I know there are a lot of explanations for why this is happening but what should I be checking over. (I actually need a clamp to put on the brake boost line.) I haven't checked my pcv yet the hose is a bit crimped atm. I just need this rain to stop so I can fix my car D:<.

RedneckRicer

Sounds like a Idle Air Control Valve Issue.

Turbo-LS

iTrader: (4)

You shouldnt need a retune, sounds like you just need to make adjustments to the temp corrections.

OneBadTurboCRV

You are running a turbo with a stock PCV system? How much boost are you running?

littleblue

15psi max

Ls_dx

iTrader: (5)

do you have a catch can setup? thats free horsepower right there!

boostedEF91

should really have catch can if not.. your putting alot of pressure where it shouldnt be.

accord_raffi

why is it that every oil catch system i see on a honda only has lines going into valve cover to vent the pressure? why doesn't anyone use a vacuum source to help pull vapors, reduce blowby, and reduce pressure even more by running a line into the preturbo intake pipe? I have mine setup just off the valve cover but i want to change it since I don't see how it can run efficiently without a vacuum source assisting it.

littleblue

Just cleaned out my IACV runs as smooth as a babies bottom now

PeakBoostSi

Im glad someone else thinks this also...!??? The stock configuration has it that way...I have two on the fron t and two on the back of my valve cover all goint to a T1 catch can kit...but why not have one to a vaccum source like you mentioned? Into the intake pipe right before the turbo? We could just use that section of an intake pipe and reweld accordingly...???

Any thoughts on this?

littleblue

Ok I went back out to grab some lunch and It started to idle the same way 800-1200ish up down up down. My pcv valve hose is flattened, could this be a sign of a issue? Also recently I have noticed my vac going to 25ish then my brakes not working. it's not very fun at all.

littleblue

Ok I did some re-checking on all vacuums the charcoal canister was missing the top vacuum line, I blocked it off. I did forget to bleed the coolant after I reinstalled the IACV that could explain the strange idle when the thermostat inst open. I'll have to do that after it cools down.

accord_raffi

when is your vac at 25hg? Mine goes to 25 when i'm off throttle while driving. at idle i'm at 21ish hg.

littleblue

Ya your right when I am off throttle it does. I am going to get the air out of my coolant tomorrow, that might be the only cause of a up down idle everything else seems to check out okay. It will happen occasionally as well. I know Boost>NA but damn I hate little problems like these. It's all worth it in the end.

OneBadTurboCRV

Let’s state something that might help you.

What does a PCV System do? Well it stands for Positive Crankcase Ventilation. This system not only relieve built up pressure in the engine from the combustion process but also gives a way to run the unburnt fuel vapors that slipped past the rings to go back into the intake. The PCV system works off of vacuum; this is why there is a check valve to block any positive pressure. How would you get "positive" pressure from a Natural Aspirated motor you may ask (this is assuming of course you have a stock motor )? From back fires or other similar occurrences. If you car back fired hard enough with out a PCV Valve it could possibly blow your seals in your engine or if powerful enough maybe even cause your motor to try and turn the opposite way.

All this is obviously bad. Now look at a Forced Induction vehicle. You are adding positive pressure air into the engine. Look at a PCV Valve and you will see there is no true positive check valve. This valve still allows air to be pushed back into the crankcase. Not only that but that pressure "bleed back", if you will, will be compounded with the pressure that is already most likely seeping past your rings. Well along with the turbulence in the oil amongst other things going on in your engine, air will be forced through the PCV Valve and back into your intake. With this air will be oil contamination (you also see this is a N/A vehicle as well).

The oil will only plug things up and build up more gunk on your valves. Anything over a few pounds of pressure and you really should get rid of the stock PCV System. You are well beyond the means of utilizing it.

Do yourself a favor and get a catch can setup. Your motor will be a lot happier.

For the people wanting to get vacuum involved with their catch cans… What would the benefit be? Also how would you control the vacuum and make the catch can work? Basically if you made a catch can work with vacuum then you may as well have left the stock PCV System on the car. Remember on your stock intake elbow (before the TB) you had a hose run from the valve cover to the intake? This was your true Crankcase Ventilation System. So when you think about it, the vacuum had nothing to do with it. Sure there is vacuum from the suction of the motor but have you ever felt the pressure coming from the intake when the motor is warm? It has POSITIVE pressure and a catch can does more than enough with out the need for assistance.

People tend to forget that when the vehicle was setup for stock daily driving there were not provisions for performance like Forced Induction. That setup works just fine for N/A but throw a turbo into the mix and you need a whole different setup.

Damn I am bored...

accord_raffi

What are you talking about? Do you know what the purpose of that original tube into the intake did? It's the beginning point of the entire system. It draws in fresh air into the crankcase to gather up contaminants that are then filtered and then exiting the pcv and into the IM.
And if it wasn't meant for turbocharged setups, then why is it that a vacuum source is still used on stock turbo setups?

PeakBoostSi

I have also seen this used on stock turbo motor setups...but i think it is mainly used for emission purposes?!? Not so much for the added benefit of the slight vaccum that it might experiece...Correct me if I am wrong still learning (and open to learn) they would rather have it be a closed loop and be self contained? No excess fumeS?

Turbo-LS

iTrader: (4)

The benifit from negative pressure in the crankcase is free horsepower to a certain extent. If you run a vacuum pump or if you really knwo what your doing you can run an exhaust vacuum system to pull vacuum in the crankcase. this is a delicate thing and cant just be hacked up and turned on.

you can pull to much vacuum on the crankcase as this pulls oil from the surfaces that need oiling. there is a fine line but it will free up horsepower most definatly. even just simply adding a catch can frees up some hp but the vacuum will do more.

accord_raffi

well if i'm running my line from my intake piping before the turbo, wouldn't that be safe since that would have the same vacuum as the stock intake piping?

Turbo-LS

iTrader: (4)

no you shouldnt run vacuum lines to the intake period IMO. just vent to the atmosphere