Hey there. When did this *idle* start doing what it's doing???? Did it ever idle different???

If it idled good once before, and not now, what maint did you do to the car inbetween???

 

I was thinking back to when this happend to me, the wires in the TPS connector were also shorting out.

If you try to raise the idle to much without ANY adjustment to the throttle position, this will happen. So if you bypass to much metered air or unmetered air, the engine will rev up to a point and bounce like its doing now. I tested this on my engine last year because I was trying to design an electronic cold start but without any adjustment to the throttle opening while rasiing the idle, the engine will eventually bounce right around 1500-1800. So possibly check for vacuum leaks, which I always say with allow the engine to run rough but I have been surprised on many occasions, Also try disconnecting and blocking off the BACv and AWS and air intake nipple for the 2 and see if that helps. This will tell you if one of them are sticking, disconnecting them electronically wont tell you this.

 

I was just reading the FSM and thought of a couple more ideas. There is a air bypass solenoid valve that is used to assist the BAC during warmup. The valve is located on top of the intake just to the left of the intercooler (pass side). I can see it clearly in the video. It has a 2-wire connector and 2 vacuum hoses. Pinch one or the other hoses closed and see if the idle stabilizes. There is also an air supply valve that is used to increase the idle speed slightly when the steering wheel is turned left or right (p/s load). It is located at the rear of the upper intake manifold and it also has a 2-wire connector. Unplug this connector and see what happens. I noticed you don't have p/s, so if this helps your idle, you can leave it unplugged. This valve makes more sense than the thermowax now that I think of it, as your idle only hunts 150 rpms.

 

I tried to duplicat this this morning without success. If a vacuum line was taken off it just idled crummy. Some up/down but not like the video and it was the BAC causing the up/down. NOTHING lke the video.

Tell you what though. I played with the water thermowax screw by letting it all the way counterclockwise. The idle picked up and went to the 1100rpm range becacuse the throttle plates open more when that screw is backed off counterclockwise. The engine remains running SMOOTHLY (like yours in the video).

While the rpms did not go up/down in a rythmic fashion, I can't but help thinking you GREENBUDD, NEED to go out and turn this screw all the way CLOCKWISE to get your idle down from the state it's in. Those throttle plates just HAVE to be cracked open a bit. After you do that, then make SURE you set the tps again. Use your RTEK and set it to 20 AFTER the engine gets HOT.

I don't think the author of this thread is reading it anymore.

The car looks decent and sounds pretty good. Keep after it.

 

That's why I suggested pinching off all vacuum hoses as well as air injection hoses to see if there were any changes. The idle-up valve for power steering has no hose, so disconnecting it would be one way to check it. He removed his p/s. This guy isn't giving us feedback, I'd like to help him fix his problem....it should be simple, as it's not a rough idle, just a hunting idle.

 

good info. dont mean to thread jack, o yes i do but i have a NA that has a idle problem. its runing at just over 2000 rpm. it warms up quick but the idle never changes. i have some responce to the AAS screw on the top of the throtle body, can change it about 200 rpm. when i have the AAS screw all the way in so lowest idle i can get which is about 2k the car kind of stuters on start up i have to give it a little gas then it jumps to 2k. i also whent around pinching vac lines with no change. i was messing with the tps and could never get a voltage out of the conector ( nothing more then 1mv ) even when adjusting the tps all the way in and out. but when i got it in it started to click constantly. so i started just playing with it and when i moved the throttle it clicked just once and if i got to a certian point it would start making a clicking noise( like a card in a spoked wheel, almost ) car was a auto converted to a maual. its a 89 GXL. i know very little about messing with the electronic systems but im trying to learn. also your mentioning all the abreveations of stuff and i dont know where to find them what they look like or how to check them. so a little explanation of where the different things can be found would be awsome. Thanks.

 

[QUOTE=tiresmoke;7001344]good info. dont mean to thread jack, o yes i do but i have a NA that has a idle problem. its runing at just over 2000 rpm. it warms up quick but the idle never changes. i have some responce to the AAS screw on the top of the throtle body, can change it about 200 rpm. when i have . ************************************************** *************************

IF you have a engie that is running at 2000 rpm and never changes, then you have throttle plates that are not fully shut. Why? Got me. Nobody would write that and not have checked to see if the throttle cable was toooooo tight and holding the throttle open.

Actually having a n/a makes it easier. PUll the intake duct off the throttle body and look at the three throttle plates to see if they are cracked open a touch or not. They probably are. Do this with a fully HOT engine so the water thermowax isn't the reason the plates are cracked open.

Anytning that is holding that high a *idle* must have the throttle plates cracked. Well almost the only thing.

The plates don't have to be cracked open very much to get to two grand.

IF they are cracked open just a bit, then make sure the water thermowax is adjusted right per the FSM that is free and online. Fuel section of the FSM. It's hard to access that device on a non turbo without removing the throttle body in my humble opiinion.

 

iv already checked the throtle cable and loosend it up so it actualy has slack in it so i know its not that. and what is FSM?

 

You can close the plates further if they are held open by turning the TB linkange clockwise from the front, the throttle stop is on a stiff spring so you have some play in the other direction.

Remove the dashpot from the rear of the TB, its the brass round looking thing on the left sticking out like a sore thumb when you remove the intake elbow. After that you can easily get your finger behind there to push the cam screw on the bottom of the thermowax piston away from the thermowax to see if the idle drops.

FSM is Factory service manual.

This is what I always say to, on a few occasions though, its been vacuum leaks and the engine still runs smooth. Weird. Im guessing it depends on how rich the engine is running?

 

ok the intake has 3 ports in it. the botom is on the main shaft and the top two are on a seperate shaft. the top two stay just barly cracked but if i turn the shaft by had and shut them it has no effect on the rpm's. also a note before i did the conversion it ran at about 1k rpm. and this time when i fired it up it wandered around 1600 to 1700 rpm before making it to 2k. and when it got warm is actualy got faster up to 2.2k i took some pics of the thing i think your talking about. im visual i need pics. so i think you want me to take the thing off and there is a cam internaly that i need to push that efects the idle ( controls the choke)?

 

They should be completly closed. The primary should be held open a little.

The first pic is the thermowax and the second pic is the dashpot which stops the plates from snapping shut and allows them to close slowly

 

TIRESMOKE.......You have a non turbo. You can't really adjust or see the fast idle cam, thermowax etc unless the throttle body is removed in my very humble opinion. Although I have gotten under the car and with a long screwdriver TRIED to adjust it. It ain't happening for me.

BUT, you say the upper two throttle plates are cracked a touch??? Yes. Tell you what, on a series four NON TURBO there is a STOP SCREW that is out in the open on the front right side of the throttle body that can be adjusted. Look for it. Back it off.

The original thread starter done did gone away.

FSM is the Factory Service Manual that can be downloaded from this site if you go to the FAQ at the beginning of this site. Look under MANUALS

 

You can see everything, the problem is getting to everything. The cam screw as I call it, located on the bottom of the piston of the thermowax you can get to if you remove the dashpot and turn the screw by hand. The other screw which I tihnk is the fast idle screw, I Can't remember, but I think that is the one that you may not be able to get too.

 

If the TOP TWO PLATES are cracked open a touch, find the screw I'm pointing to in RED in the attached jpg. Loosen the jamnut and back off the screw a touch til the plates close. Then see if it idles lower or not.

Your problem could be a totally different thing. Just guessing since you said they were cracked open.

I assume this is a NON TURBO engine.

I assume you know the outer set of the two throttle plates are spring loaded to full open with a warm/hot engine and it's the inner two plates I'm talking about. NOT the outer two. They should be full open with a hot engine (outter two).

 

a vacuum leak can very well make idle surge. it happened on my TII, along with a bad tps. it was doing the exact same thing. a vacuum leak can also give u a smooth very high idle. i accidentally left a big vacuum line open on the back of my LIM and when i started the car it idled at 3k, but it idled smoothly. the original poster hasnt responded if he has checked for vacuum leaks or not so everyones just guessing still. i still say vacuum leak or tps. how long does it take to check these OP? jeez.

 

also. whys everyone on the thermowax horse? it doesnt cause surging. why would air in the system cause the thermowax to go in and out that fast? thermowax works off heat. most likely the cause of the surge is the cause of most of the high idle. so why concern yourself with the high idle when the other is more obvious. besides, the high idle could be cause by alot of stuff.

 

Well I said i waouldn't have a chance until SDunday afternoon, it's actuallymore like Sunday night but I just got back from Manhattan, I live in NJ like 5 mins from Pennsylvania, I have been stuck in NYC for the past 4 days for a seminar for my job, I'm not trying to ignore you guys i just haven't had the time, but i just put on some normal clothes so i'll go out and let it run while i pich some hoses off and what not.....

I will replace the IC w a pvc section as soon as I get a chance for better trouble shooting access, please just bear with my and don't jack my thread, I really appreciate all of the input and I'll post my results when i get back inside.

and yeah it used to idle fine before that day when it started as described in my quote....

Thanks
NJGB

 

Yes vacuum leaks can cause a "rolling idle". Again, listen to the guy's video with the volume cranked up. You can hear a distinct on-off sound as if a solenoid or valve was opening and closing inappropriately. A very consistent 150 rpm change.
I'd put $50 it's not a vacuum leak.

 

You have obviously not worked on Hondas as long as I have. They have a very similar thermal wax idle control. Countless times I have bled trapped air from those cars and instantly resolved the problem. A bubble of trapped air can prevent the wax pellet from expanding from hot coolant, positioning the idle cam on the high step. I backed off a little on the thermowax idea after I thought about it. The idle only changes 150 rpm. A properly adjusted thermowax can change the speed 1000 -1500 rpm. Like I said earlier, the air solenoid for the p/s made more sense, as it adds very little idle speed increase.

 

so i just went out and jump started it, it fires up and rises to 2,000 rpms and just purrs for like 15-20 secons and then it drops to 1500 and bounces 150 - 200 rpms just like in the video.

i just wanted to make sure i mentioned that it does idle smoothly, though high, for the first 15-20 seconds but then startes to pulsate like in the mideo. I seems like the rpms want to stay but something keeps making it drop down...

so, i piched the air hoses for the BAC Valve and it didn't make any difference as well as what few vacuum hoses i can reach or see as it is getting dark and rainy here already..., i can't reach the air supply valve right now with IC still mounted, is that the valve your reffering to with the power steering system?

I didn't remove my p/s, the car didn't have it when i got it from the previous owner, i thought maybe it just ddn;t come with it, isn't than optional for TII from 87? But i idid remove the a/c pump and bracket, might that have something to do with it?

I'm trying to make some connection between the current bouncing/cyclic idle, the way it all of sudden started that one day and the fact that it idles perfectly smooth at 2,000 when i start it for the for 15 secs but then starts surging......though now that i think about it i pretty much only start the car once when trying to make adjustments,

like I'll go out like i just did now and start it and it does exactly what i described tonight and i'll shut it off and come inside to ask for more ideas or to sulk about it..ha, but seriously, maybe i should try to start it again after its warmed up and see if it idles smooth again for th efirst 15 secs or if it immediately starts to bunce..

so i'm gonna replace the IC with PVC and try to investigate more, i guess disconnect the tps or move it to see if it changes, maybe pinch more vac lines( which were replaced right before i get the car when the rebuilt motor was swapped in), what specific things should i do/check??
thanks, you guys make it easier to keep at it..

 

We thought you had disappeared haha. Before you make any adjustments to your tps, try unplugging it first. If the idle stabilizes, then we can suspect that it's out of adjustment or maybe a "dead spot" in it. If it's still hunting, then remove the intercooler, find the p/s assist solenoid, it's on the back of the upper intake, has 2 wires, looks like a small "can", and has no vacuum hoses. Unplug it. Re-install the intercooler, and fire it up. If that fixes it, leave it unplugged since you don't have p/s. If the idle still hunts, bypass the intercooler as planned so you can watch or feel the throttle for movement. Another thought, if the "rat's nest" as it is often called, hasn't been removed, try unplugging the vacuum solenoids one at a time. Each solenoid connector has a different color, there are normally 4 or 5 of them together on one bracket near the oil filler pipe. Let us know if one of those makes a change.

 

No I haven't dissapeared, just been way too busy, I 've been going on only four hours of sleep a night and thats too little for me, some of the gusy on here are funny, like "OMG how long does it take to check these things!!" It's gonna take me a bit since I wasn't even in the same state as my car....

But thanks for the suggestions, depending on what time I get home tonight I might stop at Home Depot and pick up the PVC parts. I can't even get to my TPS without the IC removed, so I think I'll just do away with the IC for this entire troubleshoting process. Does any one have a list of parts for this piping, pvc diameter, what elbows?

So:
1) Construct and install PVC IC replacement
2) Start car and allow to warm up then unplug TPS and note if there is any difference
3) Pinch hoses on the Air Bypass Solenoid Valve( what you referred to as the AWS earlier in this thread right?) and note any changes
4) Unplug the Air Supply Valve Solenoid Valve( what your reffered to as the p/s assist solenoid??) and note any changes
5) Unplug the color coded vacuum solenoids one by one and note any changes


Just a note, the BAC Valve, Air Supply Valve and the Air Bypass Solenoid valve have all been tested for the proper resisatnce and 12v click and all passed previously, after this idle condition had came about..

Am I missing anything, or reffering to the wrong parts??Should all of the changes be made while the engine is running or unhook and then start back up??

Thanks, now I am off to work again, be home later tonight to read any replies.

Also thanks Hailers for the pictures regarding the IC removal and location of those screws. i appreciate everyones help, except for those impatient guys, jk

Hope everyone has a good day.
NJGB

 

You've got it right. Do those things and report back to us your findings so we can help get you back on track. Also, it's generally a good idea to turn the ign switch off before unplugging connectors to prevent any voltage "spikes" from potentially harming the control unit, pretty unlikely though.

 

Well I just bought the pvc pipe and two 90' elbows this morning, it was like 5 for 5' of pipe and 1.50 for each elbow. Maybe after work I'll have the time to install the pvc setup, if it isn't raining.

Does anyone know if there is a write up for this procedure, if not I'll take pics and make one for referance sake.

 

for what the he#$%^^& its that for?(pcv pipe and elbow)