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Looks way better, make sure you bleed all the air out of the cooling system
Thanks!
Removing TB from car next, but Honda service manual diagram and Chilton’s removal instructions are a bit confusing. I have D16Y8 engine but don’t appear to have any hose connections including the one circled in pic below from service manual. Also, Chilton’s says “label and detach all vacuum hoses.”...???
That said, I plan to use the following TB removal procedures:
1. Disconnect negative battery cable.
2. Remove air duct from TB.
3. Disconnect electrical connectors (2 on TB, 1 on IACV). 4. Detach throttle cable. 5. Detach and plug coolant hoses. 6. Remove TB mounting fasteners (4). 7. Remove TB.
8. Remove old TB gasket, clean surface, and replace it with new one.
At what point do I bleed all air out of the cooling system and how do I do so?
That pic could be for a different year engine, just label/mark what you have and you should be fine.
For bleeding the coolant, have the nose of the car elevated, either with jackstands or ramps.
Fill the coolant, squeeze the upper hose a few times to suck some more.
Start the engine, have the heat all the way hot but no fan, no lights, no radio, no electrical accessories on. You'll be doing the idle relearn at the same time as the coolant bleed.
Let the engine runs until the thermostat opens/fans cycle twice, like 15-20 mins. Make sure you keep the coolant as full as possible, if you have a spill free coolant funnel they are perfect for this.
After the fans have cycled twice you can rev the engine a few times to help push bubbles out.
Once you're satisfied, make sure the bottle is full, put the rad cap on, and shut down the engine.
Then one the car is on all four tires again I like to take it for a drive to make sure everything is ok. Once you get back and the engine is cool check the the level and keep checking it for the next few days afterwards.
That pic could be for a different year engine, just label/mark what you have and you should be fine.
For bleeding the coolant, have the nose of the car elevated, either with jackstands or ramps.
Fill the coolant, squeeze the upper hose a few times to suck some more.
Start the engine, have the heat all the way hot but no fan, no lights, no radio, no electrical accessories on. You'll be doing the idle relearn at the same time as the coolant bleed.
Let the engine runs until the thermostat opens/fans cycle twice, like 15-20 mins. Make sure you keep the coolant as full as possible, if you have a spill free coolant funnel they are perfect for this.
After the fans have cycled twice you can rev the engine a few times to help push bubbles out.
Once you're satisfied, make sure the bottle is full, put the rad cap on, and shut down the engine.
Then one the car is on all four tires again I like to take it for a drive to make sure everything is ok. Once you get back and the engine is cool check the the level and keep checking it for the next few days afterwards.
Thanks, I appreciate the detailed reply!
Hmm? Service manual is definitely same year as car, but it is what it is; so I’ll go ahead and label/mark the hoses I have, which I believe are 2 coolant hoses in IACV. That said, what’s the best way to cap these hoses off, when removed?
Ah, bleeding is done AFTER I install the salvaged TB and while I’m doing idle relearn...Got it !
Unfortunately, I don’t have a spill free funnel or the spare change to buy one. So, I’m going to have to do the best I can without it.
As for installation of salvaged TB, one thing I’m confused about is how do I measure to make sure the throttle cable has “0.39-0.47 inches of deflection”?
Well, my original parts look MUCH better than salvage...
Probably could reuse IACV o-ring and coolant hose connectors on salvaged IACV are all rusty, compared to original. Also, salvaged TB ?TP sensor? connection housing has large chip broken off.
That said, since the CEL code was P1509, idle air control valve circuit failure, I’m considering attaching salvage IACV to my original TB...
It is definitely a good Idea to remove the IACV sensor because the valve that you can see needs to spin freely and easily. It's easier to clean both ends using liquid wrench, if the sensor is separated.
I did it, but I can't remember which method I used. It was either.
-cutting slots into the bolt heads and using a flat head screwdriver.
Or
-using a manual impact screwdriver (basically a thick screwdriver that ratchets when you hit it with a hammer)
I think I tried the cut slots first then the impact.
you can try that, up where i am those screws dont usually come out.
and if you have a new oring i'd use it
Originally Posted by mac25
It is definitely a good Idea to remove the IACV sensor because the valve that you can see needs to spin freely and easily. It's easier to clean both ends using liquid wrench, if the sensor is separated.
I did it, but I can't remember which method I used. It was either.
-cutting slots into the bolt heads and using a flat head screwdriver.
Or
-using a manual impact screwdriver (basically a thick screwdriver that ratchets when you hit it with a hammer)
I think I tried the cut slots first then the impact.
Thanks!
Use new o-ring...👍
Perhaps, I’m misunderstanding but aren’t these Idle Air Control Valves (IACV)?
That pic could be for a different year engine, just label/mark what you have and you should be fine.
For bleeding the coolant, have the nose of the car elevated, either with jackstands or ramps.
Fill the coolant, squeeze the upper hose a few times to suck some more.
Start the engine, have the heat all the way hot but no fan, no lights, no radio, no electrical accessories on. You'll be doing the idle relearn at the same time as the coolant bleed.
Let the engine runs until the thermostat opens/fans cycle twice, like 15-20 mins. Make sure you keep the coolant as full as possible, if you have a spill free coolant funnel they are perfect for this.
After the fans have cycled twice you can rev the engine a few times to help push bubbles out.
Once you're satisfied, make sure the bottle is full, put the rad cap on, and shut down the engine.
Then one the car is on all four tires again I like to take it for a drive to make sure everything is ok. Once you get back and the engine is cool check the the level and keep checking it for the next few days afterwards.
Ok, well...I replaced the IACV and bled coolant system as described. A few minutes in, the idle started bouncing between 1,000 & 2,000 and never stopped.
I took car for a drive as suggested and it seemed to be running much better than before I replaced IACV. It was idling a bit higher than usual, at about 1,300 but not bouncing like during bleed EXCEPT when I got back home and put it in park, then it started bouncing between 1,000 & 2,000 again.
Remove air breather lid. Start engine, get it to surge.
Confirm my guess by using your fingers to block the open ports in the neck of the throttle body, (visible, just look in there) ....see if that brings the idle speed down to normal or below, that would indicate the unwanted air is entering through the IAC
See picture and arrow pointing at the slot, looks like the valve is slightly open in this pic...... you need to make sure the moving parts of the IAC valve are actually free to move and not stuck. The thing is an electrically controlled rotary valve and it needs to move freely though its range (passage fully closed to fully open)l. They get gummy and stick especially when they sit unused for a long time
Remove air breather lid. Start engine, get it to surge.
Confirm my guess by using your fingers to block the open ports in the neck of the throttle body, (visible, just look in there) ....see if that brings the idle speed down to normal or below, that would indicate the unwanted air is entering through the IAC
See picture and arrow pointing at the slot, looks like the valve is slightly open in this pic...... you need to make sure the moving parts of the IAC valve are actually free to move and not stuck. The thing is an electrically controlled rotary valve and it needs to move freely though its range (passage fully closed to fully open)l. They get gummy and stick especially when they sit unused for a long time
Thanks!
Is this air breather lid? How do I get the engine to surge?
FWIW: That picture you put arrow on has my original parts and I replaced my original IACV with the one I bought from salvage yard.
Ok I musta had the wrong engine style pictured in my head when I wrote that.
Pull off the rubber tube so you can find the air passages (holes) in the throttle body.
Ok I musta had the wrong engine style pictured in my head when I wrote that.
Pull off the rubber tube so you can find the air passages (holes) in the throttle body.
No problem, thanks!
Ok, so if I pull off the rubber tube I’m going to see 2 air passages (holes), black arrow coming from IACV and white arrow is not. Do I need to block both to test or just the hole coming from IACV? Also, Im a bit confused by what you mean when you say “Start engine, get it to surge”.
So try covering those holes in the throttle body and see if the idle goes normal
Ok, thanks.
Stillt a bit confused by what is meant by “Start engine, get it to surge”.
That said, when I covered the hole by white arrow the idle stopped surging and when I covered the hole by black arrow coming from IACV the engine stalled.
Your goal is to figure out why the base idle speed is too high.
Per your post:
Got it, thanks!
Started engine, waited until idle bounced (surged). Then when I covered the hole by white arrow the idle stopped surging and when I covered the hole by black arrow coming from IACV the engine stalled.
and when I covered the hole by black arrow coming from IACV the engine stalled.
The IAC valve is probably stuck open (lower passage leads to the IAC)
The upper hole should lead to the large screw that's used to dial in base idle speed, but that really can't be done if the IAC is not in proper working order
Sorry for not being prompt, been kinda busy lately.
The IAC valve is probably stuck open (lower passage leads to the IAC)
The upper hole should lead to the large screw that's used to dial in base idle speed, but that really can't be done if the IAC is not in proper working order
Sorry for not being prompt, been kinda busy lately.
No problem, thanks, I appreciate you taking the time to help and share your wisdom.
Others have suggested since the white arrow hole leads to the idle adjust screw. This means that the idle surging may be fixed by simply adjusting the idle speed as instructed in the service manual. Alternatively, the idle adjust screw O-ring is bad and needs to be replaced. Start with the former.
FWIW: I did remove, clean and work back & forth the IAC valve for several hours, but apparently to no avail.
That said, the idle only appears to surge while in park but with A/C on in park and while driving it does not, so not really sure how to proceed.
Does it still have code P1509?
Was the code erased, and has it reset same code?
The CEL is no longer coming on.
That said, I’m cautiously optimistic that the issue may be resolved, somehow. Just driving the car around since I re-cleaned the IAC valve and re-bled coolant, I appear to no longer have a surging (bouncing) idle issue, as it settles in around 600-800.
To me, the real test was putting the car in park with no a/c, which within 5 minutes of starting the bleed & re-bleed and immediately after, I’d get the bouncing idle. But when I got home the past two days, I sat in park with no a/c for over 5 minutes and idle stayed around 600-800.
05-14-2019
