AIV Repair/Removal, sticky?

Post by **Chingon** » Sun Jun 22, 2003 9:05 am

hey jimmy, why don't you just get the car computer diagnosed, thats what I did and what they told me to replace seems to have fixed the problem, according to them I had a bad maf and pick-up coil, I replaced the maf with a used one off of ebay and the car works fine now

Post by **JimmyJ** » Sun Jun 22, 2003 9:05 am

Dragon: You dont spray the engine with water hehe. Sorry i wasnt specific, i was just going through the diagnostics quickly when writing.

Using a can of WD40 on the top end of the engine can expose leaks that you may have when the engine is running, leaking air will cause the fluid to bubble thus showing if you have a leak.

SOme of the possibilities were Injectors (seats and nozzles) as well as head gasket and so forth. Spraying them would reveal if there were any leaks.

Chingon: Being a mechanic for a number of years generally prevents me from taking the car in for a diagnostic until im totally sure that there is nothing mechanical oppose to electrical that could be the problem

That way i minimize the hours they spend on the car when i take it to the shop, because i have checked everything other than plugging in the coder

As i mentioned, it seems to be eletrical. Could be the MAF or TPS, thats my last resort now i think. Ill post when i find the problem.

Post by **Dragon240** » Sun Jun 22, 2003 9:05 am

Well that wouldn't expose a vacuum leak would it, as it wouldn't be blowing to make bubbles..

Post by **Hookedup240** » Sun Jun 22, 2003 9:05 am

What else did you guys use to plug up the exhaust hose with after removing the aiv, I can't seem to find anything to use around the house.

And also, how much pressure is actually going to be put on what ever i plug it up with??

Thanks

Post by **aaronsnocker1** » Sun Jun 22, 2003 9:05 am

quick question. What if you remove your airbox and just plug off the hose from the aiv that leads to the airbox?

Post by **i2ice4m3** » Sun Jun 22, 2003 9:05 am

yeah i think that would do the same thing...

Post by **JimmyJ** » Sun Jun 22, 2003 9:05 am

"Well that wouldn't expose a vacuum leak would it, as it wouldn't be blowing to make bubbles.."

I dont understand your comment...?

Post by **JimmyJ** » Sun Jun 22, 2003 9:05 am

"And also, how much pressure is actually going to be put on what ever i plug it up with??"

Very little pressure comes through those hoses. I plugged mine with screws.

Post by **Dragon240** » Sun Jun 22, 2003 9:05 am

Well a vacuum leak wouldn't expell air would it, it would suck in right? Therefore a vacuum leak wouldn't be exposed by spraying wd40

Post by **JimmyJ** » Sun Jun 22, 2003 9:05 am

Vacumm Hoses have air that runs through them which blows as well as sucks, thus creating air to allow the WD40 to bubble. Its a common way to find em, trust me

Post by **bishopant** » Sun Jun 22, 2003 9:05 am

Just wanted to chime in here with my AIV removal results. On a scale of 10, I'd say it's a level 1 difficulty. I cut a one inch slice from the metal pipe that goes from the the AIV assembly to the exhaust and slid it back into the threaded fitting with the two nickels, and tightened the fitting. I now have a much smoother and more quiet running engine. However; idle is higher at anywhere from 850-950rpms. I believe the problem lies in the vaccuum lines involved with the AIV unit. The lines are open (not plugged). I'm hoping plugging them will remedy the idle prob a bit. Will see soon, and repost my findings.

Ant

Post by **kevy8up** » Sun Jun 22, 2003 9:05 am

Ok guys.....it worked!!! for the last week ive been dealing with crappy idle. Up and down. coming to a stop. Sheesh... I pulled the AIV. sprayed cleaner on the MAF and the intake and cleaned the batter connectors off. Put it all back together and fired her up. Now, It acted up at first and was sputtering BUT, it cleared up and ran steady.

However, I took it for a drive and im pretty sure i did lose some low end torque. but I would rather loose that then deal with crappy idle at a stop. I even gunned it a few times and slammed the brakes. it dropped a bit but never stalled.

So yes it works and yes u loose some torque. thank god. I have a normal car again FOR NOW.... I will post back if it acts up again.

later Kev

Post by **Neal00** » Sun Jun 22, 2003 9:05 am

Couldn't we just stick a cork in it? Literally!

A wine bottle cork or a rubber plug coated with silicone or liquid nails stuffed in the hole on the inside of the air filter housing. Wouldn't that do the same thing?

Website · Post by **lbrowne** » Sun Jun 22, 2003 9:05 am

SO far I've done this, removed all that gear and plugged everything up. Cleaned my battery terminals...

I still have the fluctuating idle. not nearly as bad if the car is left idling, but its very present when you are driving spiritedly and have to come to a stop..... she stumbles very close to stalling out and pops back up and again and then kinda levels out a bit...

Post by **bishopant** » Sun Jun 22, 2003 9:05 am

I just wanted to add somthing. As I mentioned a couple of posts before, I plugged the vaccuum lines. But the car drove much smoother with the metal vacuum line manifold inlets open to the atmosphere (the manifold I'm talking about are the metal tubes where the vacuum lines from the AIV connect to). After I first took out the aiv assembly, I also removed the rubber vacuum lines completely from the car leaving the metal tubes open. It ran great, that's when I posted and said that the car was running "smoother and quieter". Now, I'm not sure how leaving open or plugging these affects the engine operation, but I know for sure the car ran smoother and less hesitant with them open. Someone else should try running the car with them open and post their results.

Can someone knowledgeable enlighten us of the affects?

Anthony

Post by **kevy8up** » Sun Jun 22, 2003 9:05 am

I think ill be a lil offended by the little Knowledgeable comment. You have over thirty people who have tried this and the only ones that have POSTED that it DIDNT work are the ones with just more than the AIV problem.

as far as OPEN lines. Are u for real. I know enuff to know that then engine is basically a vaccum and u open a line a little bit and u lose power to the vaccum. So i realy wonder how yer car is running at all with all the lines OPEN. if you would have done this right you wouldnt be posting back at all.......like everyone else.

and for someone to open the lines back up......WHY???? especially when the cars are all workin with them closed. Looks like yer the first one to have yer car work with the lines open.

Post by **bishopant** » Sun Jun 22, 2003 9:05 am

Kevy,

What you should be thinking is how to contribute in a positive way and not in one lessening the precious time we have in our lives. The real reason I'm posting is merely to state the facts and ask someone who has had those two lines open or who can explain what is technically happening by doing this to reply with knowledge.

knowledge : 2 a (1) : the fact or condition of knowing something with familiarity gained through experience or association (2) : acquaintance with or understanding of a science, art, or technique b (1) : the fact or condition of being aware of something (2) : the range of one's information or understanding <answered to the best of my knowledge>

By the way, I removed the rubber caps I placed over the vacuum lines to seal where the hoses were attached to see if it would run differently. Yep, runs smoother. MUCH SMOOTHER! Again, let me say that I don't know if the engine is being affected negatively by doing this, but just stating how the engine is running after removing them.

Ant

PS Just because I only have 8 posts doesn't mean I'm a moron. I spend most of my time on these types of boards reading not typing and trying to fit in.

Post by **p00t** » Sun Jun 22, 2003 9:05 am

Guys no need to argue.

If the rest of your car is functioning properly leaving the little lines uncapped will degrade performance.

Sounds like you have a problem elsewhere. The two small lines that hook up to the AIV are vacuum (red) and an atmospheric line (blue). Leaving the atmo line open shouldnt really hurt you. But the red one left open will allow unmetered air to flow past the MAS sensor and you will be running leaner.

What this sounds like to me is a faulty EGR valve. When you have the AIV vacuum line disconnected you are allowing that line to be near atmospheric pressure, leaving any other components that rely on that line to pull valves open to remain closed.

This can effect other things that rely on vacuum as well. Be sure to check EGR, SCV, and FPR valves.

Basically neither of you are wrong. His car probably does run smoother with the one vacuum line disconnected. But it also indicated a problem elsewhere that needs attention. :thinker

Post by **CanadianCoch** » Sun Jun 22, 2003 9:05 am

Well I decided to try this aiv removel this afternoon and found it extremly easy and made my engine look a lot less cramped, lol. I plugged the two small lines with screws and made sure they were tight, and put 2 dimes in the hose with a clamp type deally around those, and was amazed how easy and good it looks. It took almost as much time to clean all the mess under the AIV then it did to remove it. I initially took it out for a ride, and must say it seemed to get up a bit quicker, and my idle stayed perfect. I was extremly pleased with the resuts.

HOWEVER. I then installed my system back in my car (took it out because I just moved). Upon installing it I had to take it out and test the bass(parents don't like my bass on the block) so I took it out and got my butt a massage, lol. on the way back to the house I turned off the music a block away, and proceeded to stop and back the car up. all of a sudden my idle went to hell, going between 500-800 like crazy, for about 25 seconds. Does anyone know why, or how to stop this? It got close to stalling, and I definately don't want that on the way to school tomorrow!

Post by **Dragon240** » Sun Jun 22, 2003 9:05 am

Maybe one of the hoses came unplugged?

Post by **CanadianCoch** » Sun Jun 22, 2003 9:05 am

I double checked the two small hoses, and they are definately plugged, as is the hose that goes to the header. I understand the reason for plugging those two small vacuum lines, however would unplugging the hose going to the header hurt anything ?

Post by **kevy8up** » Sun Jun 22, 2003 9:05 am

For me....the only bad thing about takin the aiv out is, now my car MUST warm up for 5-10 minutes before i can drive it or it will have a crappy idle till it does. I cant wait for winter...booooooooo....lol make sure the line to the exhaust is completey sealed or u will loose back pressure there also.

Post by **GroundZero** » Sun Jun 22, 2003 9:05 am

CanadianCoch wrote:I double checked the two small hoses, and they are definately plugged, as is the hose that goes to the header. I understand the reason for plugging those two small vacuum lines, however would unplugging the hose going to the header hurt anything ?

your car will run like crap and you will more than likely foul your plugs if you leave the header hole open

Post by **bishopant** » Sun Jun 22, 2003 9:05 am

POOT,

Thanks for the "helpful" response. Which is the red one? I threw out my old lines (DOH!). Is it the one coming from the metal vacuum tubes or the one coming from the intake? In FSM: Metal tubes direct to AIV solenoid is #5. The other line is T'd to the intake; #9 and #6. If it's 9 or 6, should I plug between the metal tubes and the intake and plug the intake too, or plug between the intake and the AIV (as per the instructions in this thread)?

Thanks again

Post by **p00t** » Sun Jun 22, 2003 9:05 am

i dont have my car or fsm with me ATM. I believe the metal line on the intake manifold to AIV is the blue one, most likely atmo line... but im not sure where it snakes to. just plug it.

The red line T'd off the plastic intake is the vacuum line , one side of the T runs to the AIV the other runs backward behind the intake manifold.... most likely to the egr.... but im not sure. I remember there being one line next to the T one on the plastic intake, mostlikely went to Idle control valve, just FYI.

Post by **Toms240420** » Sun Jun 22, 2003 9:05 am

I love p00t. it is the great mediator

Post by **bishopant** » Sun Jun 22, 2003 9:05 am

pOOt,

Thanks.

Post by **Yorb** » Sun Jun 22, 2003 9:05 am

this is an extremely informative and interesting thread, thanks p00t (et al)!

i'm a n00b but i find myself in this thread because i have been having some ****ty-*** idling this afternoon. its fine for a couple minutes as it warms up, but once its warm then it periodically drops to 200-300rpm. it immediately shoots back up to 1.5k and then drops back to normal, but then in another few seconds itll drop again. i havent had it stall yet, but it's making me paranoid enough to keep it revved at stoplights. if i run it with the hood up i hear this sound coming from the oil cap area (though i cant pinpoint it) like something rattling around almost, or the 'marbles' that someone else described.

i am a complete car n00b, and i am without an fsm as well, so i greatly appreciated p00t's pictures and dumbed-down explanation. =P i think i'm ready to tackle the job now if i deem it necessary. i'll probably want to leave the AIV in though, since i dont want the car to run ugly or need 10 minutes to warm up.

question is this: are there other things i should check first? after reading through the faq and searching other threads, i hear 'checking the plugs' a lot. someone wanna tell me in laymans terms? screwdriver, take them out, look for what? could this even be the cause of crappy idle?

i also hear that the o2 sensor could be the prob. how do i check it? where's the ECU for an s13? boy i wish i had an FSM =<

thanks guys...

Post by **Dragon240** » Sun Jun 22, 2003 9:05 am

ECU is behind the passenger kick panel...

Post by **bishopant** » Sun Jun 22, 2003 9:05 am

Update:

As I mentioned, I removed all vacuum lines involved with the aiv completely from my car when doing this removal. I did this to keep the engine bay clean.

Last night I plugged the middle metal vacuum tube that was linked to the aiv solenoid via a vacuum hose which helped my idle drop to a more normal speed. Note: I also have the third metal tube T'd to the intake hose like original specs. Now, it idles at approximately 600 at cold start, 700-750 soon there after and levels out when warm between 750-850. What more can I ask for right. I'm gonna check my timing soon and adjust idle to a normal 700-750 pretty soon here. Hope I helped.

Ant

AIV Repair/Removal, sticky?

IT WORKED FOR NOW....woohooo

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