marcyprojects

I am about to punch my 99 in the face! I have spent over $1K on it in the last 2 months, only had it for 3. Still cant trace down this idle problem. Same thing you hear about out here, RPM drops to 500 while sitting at idle for more than 15 seconds, noticable vibration, occasional stalling when I dont keep the A/C running at all times. Ive done just about everything one could think of after a ton of research and a ton of labor with my scanner.

Im not throwing any codes at all so I dont know where to look. Only thing I havent done was start replacing O2 sensors which is the only thing left I can come up with. I rebuilt the entire top end of my S13 years ago and even it didnt give me this much trouble! Heres the list of what I have done. Any tips or ideas, experiences would be appreciated.


6 New OEM Coilpacks from the dealer
OEM knock sensor
NGK G power plugs
Cleaned MAF
Cleaned TB
STP engine clean (similar to seafoam, wal mart was out.lol may try the real)
Checked grounds/Added Extra Grounds
New Air filter
New Fuel Filter
Swapped crankshaft sensor from junkyard (the one by the oil filter)

ChrisMan287

iTrader: (34)

Try cleaning your IACV.

marcyprojects

ill take a look at it tomorrow. know of any good write ups with pics?

marcyprojects

by the way, wouldn't the STP/seafoam clean this anyway?

SethGreen

If you IACV is faulty it will cause this and you will have to replace it. You can tear it apart and clean it but If its gone bad it wont help.

marcyprojects

cleaned the IACV to the point I could see my reflection off it. put it back on, started up, acted like it did the trick and then the problem came back. definately made a difference and made things smoother but still not holding the idle right. Still no codes, no nothing. Runs like butter with the A/C on though? I also noticed when accelerating and coming to a quick stop, RPM drops down to almost zero sometimes? not sure what to do now. Does this mean I have a faulty IACV?

VQ'rInWLA

iTrader: (83)

Might need to adjust tps. Was the OEM IACV setting ever fuccked with?

marcyprojects

its possible. I did move the idle screw a bit to bump the idle when the problem orignally occurred. I moved it again today to set the idle back to normal but it may need an official "reset". I think I saw a write up on this in the NICO forum but I couldnt quite interpret them. Anyone have some good instruction on how to do it right?

VQ'rInWLA

iTrader: (83)

What are you idling at normally?

marcyprojects

600 when running good under load in drive. 700 with A/C running. 650 in neutral

VQ'rInWLA

iTrader: (83)

Try this: Unplug tps and start car. Adjust IACV or throttle set screw (not recommended if it was never touched) and set idle a bit higher than you'd want it. Once done, turn off car. Plug tps back in. Start car. See how that works and report back.

VQ'rInWLA

iTrader: (83)

Might take a few tries to get it right but youll get the drift when you give it a shot

cashoit

It def sounds like your IACV has crapped out.

Like VQ sd, u can adjust the idle screw on the TB such that the TB is always cracked open a bit. this is if you dont wanna replace the IACV. There is a test for the IACV per the FSM. Test it.

aackshun

iTrader: (3)

This sensor is only needed for starting the vehicle effectively.


No, if your IACV crapped out your car would have the "Honda Idle" as I'd like to call it (Honda IACV's fail quite often...)

Errr well that's what mine did when I killed it.... IACV's don't fail too often on our vehicles, that would be the laaaaast thing I would check/replace/fool with.

JNCoRacer

iTrader: (6)

Vacuum leak? Thats what I found on my 99 this weekend. The gasket between the upper and lower intake manifolds is old (reused the original one when I changed VC gaskets). Just picked up a new one from Courtesy.

cashoit

Yo whats good Aack mang!! U got the your car running yet? I was down in Dallas like a month ago. Sghould have gave yall texas boys a shout. Check out the red devil even if it is out of commisision

And what the hell is a Honda Idle lol?? Some of us have never owned or worked a honda before!

The test for the IACV is a simple resistance test. Why not just test it

marcyprojects

yea i think it is very odd that the IACV is bad but at this point anything could be possible. With that being said I guess I could have good luck getting another at the junkyard which I will probably do this weekend. Im at work now but ill try reseting the TPS as suggested. I did something similar to the process that everyone is talking about but maybe I did it wrong or maybe it didnt take. ill keep you posted. thx for the help everybody.


BTW, im new to the VQ but I know KA24DE like the back of my hand if it will help anyone

jholley

iTrader: (13)

Don't forgot to warm the engine before adjusting the TPS. You need the TB plate fully closed touching the screw before performing that procedure.

marcyprojects

ok so run the car up to WOT, shut down, un plug TPS, start up with TPS unplugged, set idle high a bit, shut down, wait a minute and then restart?

sounds easy enough. I think I may have had the order wrong when I tried to do this yesterday. hopefully this works. it still seems a but odd that IACV would give this kind of trouble. I'm also starting to think it wouldnt be a bad idea to try and pick up a MAF as well though mine looks mint and has been cleaned twice now.

VQ'rInWLA

iTrader: (83)

Plug tps back in when you shut it down. Then start it

marcyprojects

right, my bad. Also, ive seen 2 different types of TPS out there. one has a single electrical connection like mine and then theres another that has 2 connectors. I was wondering if this is possibly a recall that I should have? or maybe it just signifys when my motor was produced? just curious since were talking about it.

VQ'rInWLA

iTrader: (83)

That I cant answer. Couldve sworn they were interchangeable through 4th and 4.5 gen....

ShocknAwe

iTrader: (3)

Your IACV could be bad. It can really only take about 2 cleanings. There is a plunger that moves back and forth. YOu can take this part out and then turn your key from off to on and see if the plunger moves. If it doesnt move then it is bad

marcyprojects

well boys it seems this rain just started pouring. I really just want to get rid of this F*** car but I cant because I have $1k invested!

It seems I have a rear valve cover leak. Noticed it on my way home from a buddys house today. Had light smoke coming from the passenger headlight and the engine got a little noisy. Im hoping this new noise is because of my oil loss though the leak doesnt seem to be spraying or squirting. I see fresh looking oil covering one of the bolts on the exhaust, and near the PS high pressure hose. the idle is a bit high now as well but the previous vibration is gone(strange)

So my question now is, would this leaky gasket be the cause for my idle issues? I am thinking that this gasket leak might me causing some sort of a vaccum type leak?

Ill be tearing into this over the next few days, hopefully I dont destroy this car but theres no possible way I could afford to pay any mechanic to do this.


Where is my S13 when I need it man! that was the most reliable car I ever owned!

VQ'rInWLA

iTrader: (83)

A vacuum will definitely throw your idle off and have you run like siht. Get it taken care of and readjust to compensate fix and youll be tip top.

marcyprojects

so I went midnight mechanic style and dove into this tonight. took me about 2 hours to get the manifold off. Not to bad according to whats been said out here on the forum. Anyway I inspected the gasket and it didnt seem like it was in terrible shape, I have surely seen worse. I did see where the oil seems to be seeping out. Theres a couple of very small gaps, mainly in one corner, where the oil seems to be getting out. Im guessing this is enough of a "vaccum" like leak that could be the cause for the stumble? Hopefully so. Ill be picking up another gasket tomorrow as well as changing the oil while im at it.

Also, I discovered this leak while attempting to reset the TPS and I still cant get it. I have NO idea why. I unplugged what I thought was the TPS, started the car, and it ran for about 10 seconds and died. I unplugged 2 connectors mounted right on the side of the throttle body, one red and one gray. Initially I thought the TPS was on the IACV? I think i confused myself here.

VQ'rInWLA

iTrader: (83)

Connectors on the right side of TB is TPS. Those are the ones to disconnect for the procedure.

QT1 5MT AE

iTrader: (6)

also get a new pcv valve

marcyprojects

so I guess id better work fast when adjusting the TPS then. or maybe I did something wrong. doesnt seem so.

wirelessdude04

iTrader: (24)

Write up http://www.vqpower.com/v2/articles.php?article_id=95

tiphawk

When I changed the oil while replacing the rocker cover gaskets on an altima I got valve clicking. Doing both procedures at the same time dried those valves up. To lubricate them I had to remove the covers again and throw a tab of oil onto all the valve lifters. I suggest you do that also to prevent an valve clicking.

Don't forget to put grey RTV sealant onto the left corners. To keep the gasket from falling out of the cover while assembling I also put a thin tab in the grove of the cover.

dwapenyi

iTrader: (3)

Replace the front O2 sensor. I did the same with my friends 99I30 auto. Did a complete tuneup but the car still acted strange. It wasn't your idle issue, more like lacking power, not "synched" with the tranny during gear change etc. Replacing that front O2 fixed everything.

I've also confirmed with the FSM that the 4th gen ECU does in fact use only the front O2 to fine tune air feul readings. This is as I have suspected for some time.

DW

marcyprojects

interesting. so changing out this gasket may not do a thing... that would suck but i guess it all would have to get done anyway.

aackshun

iTrader: (3)

It's pretty easy to find a vac leak d00d.....

dwapenyi

iTrader: (3)

So you could now either change the gasket which is some amount of work, or change the front O2, which is right there.

Your call.

I will now leave you with your thoughts.....................



DW

marcyprojects

well Ive already got the manifold taken apart and I picked up new gaskets this afternoon so Ill be doing that no matter what. Ill just cross my fingers and pray. either way if it gets rid of the smoke that I saw coming from the passenger headlight area last night I can live with that slight misfire for another week. I think the previous owner of this car may have misrepresented his matinence records as I have reason to believe the motor was also somewhat low on oil. I have heard that it can also be the culprit for these kinds of oil leaks. It looked kind of burnt and dry looking inside the motor and on the underside of the valve cover. So, the motors bad performance after all the work ive already done, could be as simple as a motor basically choking due to lack of oil. So simple yet so complicated to find. As for the TPS and the O2 I may just head up to the junk yard with my cargo shorts and take my chances with a five finger pick up. Though Im also hoping that the TPS will prompt a relearn after being unplugged all night and having the battery unplugged all night.lol. update to come tonight.

thanks again everyone for their input, it has all been helpful.

dwapenyi

iTrader: (3)

You're going to pick up a used O2 sensor? Why do I even bother.

DW

marcyprojects

cut me a break man. this is my only car and im already down over a grand. Ive spend considerable money every paycheck on this car. I can scoop up one from the yard soak it in seafoam and gas for a day and see what happens. As for everything else. I changed the rear valve cover gasket and the problem persists still. Im at a total loss at this point. Very dissapointed for buying a car with all this crap wrong with it.

Pretty sure now my oil leak is a rear main seal leak. Not dripping on the ground but the oil is slowly seeping on to the exhaust downpipe and producing a small amount of smoke as it burns off. I put in fresh oil and a fresh filter along with a main seal repair fluid. Im praying that it does the trick. seems that this stuff is about 50/50 shot to work. Read up more on it and I can also try a thicker oil. Put in 4.5 quarts of 5w-30 castrol synthetic tonight. reassembly of the rear vavle and the manifold took much longer than dissaembly. Idle is riding at about 800 rpm now in park, cant get it to go down either. sux cuz it doesnt seem to be misfiring anymore. oh well... I guess Ill just ride this thing out until I can come up with another stack of cash.

jholley

iTrader: (13)

It's running like butter with your AC on because the AC step motor within the IACV is giving it more air. Sounds like your IACV/AAC is not sliding correctly to supply the right amount of air while idling. The AAC is the Auxilliary Air Control valve within the IACV. My IACV/AAC broke 2 years ago so I installed a new one. Since then she has idled nice and smooth. I got the IACV, 23781-38U05, for only $138 at courtesyparts but the price has nearly doubled to $249. If you don't have that cash then try digging for an IACV at the JY.

jholley

iTrader: (13)

If you cannot digup a new or used IACV then try testing the IACV/AAC using pages EC-309 - EC-310 of the FSM.

Here is a diagram showing all the sensors the ECM uses to operate the AAC step motor. The step motor slides the valve to control the air passage.




If you haven't touched the ECTS try replacing that. It only cost $25 at autozone.