What's up dudes?
First post on here, long time user of the forums. I love Acurazine! Owning a 2nd Gen Tl-S, these forums are like a journey back in time. I've found answers to everything, except for this... (yes I searched)

If you failed to gather, I have an idle issue. Not fluctuating per se, it's raising.

I had a low idle in P and N that was fixed by the famous TB cleaning Honda's need. A few months later, or three weeks ago, I did a full timing belt kit change/install; pulley, belt, water pump... etc. I also changed the coolant, seafoam aerosol top cleaner'd, and changed the oil at the same time.

Now my car is idling high in Park and Neutral! Not fluctuating or jumping, not low and stalling. On start it revs up to 2000rpm and slowly drops to 1000rpm. In the morning on cold start I drive 17 miles to work and when I put it in P it idles correctly around 800rpm. After work It does the same thing on start but when I get home it's idling in P at 1200-1500. If I am running errands it gets higher and higher each time I turn the car off/on. If I leave it in idle on a semi-warm start it will slowly raise from 1100 up to as high as 1800rpm. It's not bouncing, it's steady.

Since the issue started I've burped the coolant, cleaned my IACV, done a TB coolant bypass, and still the issue remains.

During the timing belt change my exhaust side crank fell victim to the 45 degree flop towards the back. I pulled it to the top and installed the belt. I don't have a knock so I am thinking everything went okay with that.

Sometimes when I am braking it feels like the car is still accelerating. I checked for brake booster vacuum leak since the vacuum leak will cause irregular idle and what not but no joy. If anyone can advise the issue looking at reads from a Live Data screen from a CRP123 Creader diagnostic tool, I'll put them up.

Ideas?

p.s - No CEL

 

to me it sounds like brake booster vacuum leak.

that's the exact thing my car did when I forgot to connect the hoses.

 

So am I looking at simply replacing the hose? What would the vacuum leak do to timing? Could the loss of vacuum cause low fuel percentage or TB plate being open wider than normal?

 

correct vacuum is critical to engine operation
Are your front and rear motor mounts good? both are vac boosted, when throttle applied it stiffens them

for good measure inspect PCV- clogged can do many things- none good
the small coolant and vac hoses under TB get swapped? that's common

Also the top most gasket- first cover removed to remove intake manifold for egr cleaning
that gasket can be installed upside down and fit but block a crucial port-
must align to cover- not manifold side - has tricked more than one~

 

how was the iacv- inside its operating bore was smooth so rod can rotate and cleaned up well?

 

There has to be some slack on the throttle cable and make sure the butterfly is at the factory position.

 

Motor mounts are good and I did the TB bypass by connecting the two hoses that went in/out of the TB. It basically just straight lined the coolant flow. The issue was present prior to that, in fact, it's better. I'm confused at what you mean by the gasket. I guess I really should get in there and clean that f**ker out too.

I cleaned that thing until it looked like nickle. The only part I got afraid of was something I saw where they said the little spinner inside of the IACV had Teflon coating... WTF is Teflon? If it's gray, I rubbed that shit off<- no pun intended} with a q-tip.

When I changed the coolant I moved the Cruise control cable under the top hose and clipped it to the stock bracket. I can see how this might cause the butterfly not to close all the way but wouldn't the symptoms be more consistent and not a steadily raising idle only after 2-3+ hot starts?

Thank you dudes so much for the input, all of it is being incorporated in my troubleshooting.

 

the gasket= when you start the egr cleaning job, first thing off top of engine is the metal cover, underneath is a bunch of dirty oil in the top of the intake manifold itself

The gasket there- between those 2 pieces, can easily be installed flipped over- UP side DOWN
when that way it looks right but blocks an important port- match the gasket to the cover to know all the holes match

no good reason to bypass the TB heater system, even with a thermoblock intake insulator spacer type device- are you track racing the TL? if not leave well enough alone
you may have hooked vac and coolant line together~

 

Teflon is on the part to improve its ability to freely move and rotate= to adjust minute amounts of air amount going thru that slit in the rod
you got that all clean, right?

 

Yeah I realized what Gasket you were talking about this past weekend. I cleaned it off and what not but it was on there correctly.

Yeah I got the valve spic and span. Everything seemed okay at first but the issue is still there. I'm losing my dang mind over it.

 

Verify the timing marks, it may have jumped a tooth somewhere.
The same happened to me when I did my first timing belt, the idle would go high then stalled. When I checked the cams it was all off. Luckily it did not destroy the valve train.
Try the front upper cover first and verify, if its ok then the rear one.

 

Dreading going back in there man.

 

Agree, verify the timing marks are correct. You dont have to remove the covers. Line up the crank to TDC and pop open the small inspection plugs on the timing belt covers on each head and make sure the line on the cam pulley lines up exactly. It can be one tooth off and not be knocking.