Finally Found The Source Of Erratic Idle ( Long w/ pics )

[Shehzada]

For those of you who have read my previous posts, I have been trying to solve my erratic idle for about 2 months now. The problem started with my cold start idling at 2200 RPMs and never going lower than 1000 RPM after fully warmed up and fluctuating between 1500 to 2000 RPMs.

WEEK 1. Tried tightening the FIV (did not work) and thoroughly cleaned the IACV (which was very badly clogged up). At this time, I took the EGR off and cleaned it too but reused the gasket. Nothing solved.

WEEK 2. Drained and refilled the radiator. Tried pulling codes (no codes stored). Nothing solved.

WEEK 3. Obtained a known working set of IACV & FITV and installed them. The swapped FITV helped with the cold start idles and brought them down to 1500 RPMs. However, still had the fluctuating jumpy idle. So, solved one (1) problem.

WEEK 4. Purchased a set of Mechanics gloves to look cool working on my car on the sidestreets of New York. BTW, I don't have a garage. This week I cleaned the TB and tried adjusting the idle screw (I have it turned fully clockwise but no good). Nothing new solved.

WEEK 5. I tried spraying water on all vacuum hoses but got no results. I somehow could hear a hissing sound coming around the EGR and thought that since I reused the gasket, maybe installing a new gasket could solve my problem. So I ordered a new gasket for the EGR.

WEEK 6. This week I was really excited about getting the job done. I thoroughly cleaned the EGR and the flange mount and installed the new gasket. I also purchased some new clamps to go over the hoses on the FITV and IACV. I tested the EGR and it held a vacuum and the solenoid seemed to be working. Guess what ? !!!!!!!!!..................... I still had the problem. Nothing solved.

WEEK 7. Now I was really stumped. But I didn't give up or washed my hands and took it to a stealership. I decided to take a hose to try to pinpoint this hissing sound. It still was coming around the EGR but the erratic idle makes it hard to distinguish it especially when the fans come on. Getting Close Though.

WEEK 8. Finally found the source of my erratic idle. There was a big air leak coming from when the intake manifold meets the head. It is close to the injector to the 4th cylinder. Not an easy job.

So here is my question. I have seen the thread by "Cokinut" and other who have swapped their intake manifold. I only want to replace the gasket. Is there an easy way to do this without taking everything apart? Is there another solution someone has done successfully?

Thanks for reading.

[accordaffair]

hmmm, its not easy, but I suspect you can just unbolt it, pull it forward and replace the gasket.

its not fun though, I despise having to remove the IM with hand tools

[MoonScryer]

If can be done, but it is tight. Drain the coolant, take the support bracket off the bottom (if you still actually have it) of the intake manifold, and take the nuts off the headstuds. Slide the manifold back, install gasket. Put it back together in the reverse. If it is too tight in the firewall area, you can loosen the rear mount and jack the engine up a bit, but that is getting more complicated than needed. The above should be able to be done in about two hours. Get the swivel head sockets from Sears or wherever - good in tight spaces.

[wed3k]

im using one of those hondata type gaskets for my h23 head swap and im having idling issues as well.

im pulling the whole head off (cuz i have a coolant leak, bah) and replacing the IM gasket with a stockk one.

[TysCb7]

that mesh screen is supposed to be rounded up, not all smushed down.

[Shehzada]

that mesh screen is supposed to be rounded up, not all smushed down.

That's how it came on my car from the factory. I didn't push it down while cleaning it. But I don't think it can make a difference, can it ?

[zacatecas]

For those of you who have read my previous posts, I have been trying to solve my erratic idle for about 2 months now. The problem started with my cold start idling at 2200 RPMs and never going lower than 1000 RPM after fully warmed up and fluctuating between 1500 to 2000 RPMs.

WEEK 1. Tried tightening the FIV (did not work) and thoroughly cleaned the IACV (which was very badly clogged up). At this time, I took the EGR off and cleaned it too but reused the gasket. Nothing solved.

WEEK 2. Drained and refilled the radiator. Tried pulling codes (no codes stored). Nothing solved.

WEEK 3. Obtained a known working set of IACV & FITV and installed them. The swapped FITV helped with the cold start idles and brought them down to 1500 RPMs. However, still had the fluctuating jumpy idle. So, solved one (1) problem.

WEEK 4. Purchased a set of Mechanics gloves to look cool working on my car on the sidestreets of New York. BTW, I don't have a garage. This week I cleaned the TB and tried adjusting the idle screw (I have it turned fully clockwise but no good). Nothing new solved.

WEEK 5. I tried spraying water on all vacuum hoses but got no results. I somehow could hear a hissing sound coming around the EGR and thought that since I reused the gasket, maybe installing a new gasket could solve my problem. So I ordered a new gasket for the EGR.

WEEK 6. This week I was really excited about getting the job done. I thoroughly cleaned the EGR and the flange mount and installed the new gasket. I also purchased some new clamps to go over the hoses on the FITV and IACV. I tested the EGR and it held a vacuum and the solenoid seemed to be working. Guess what ? !!!!!!!!!..................... I still had the problem. Nothing solved.

WEEK 7. Now I was really stumped. But I didn't give up or washed my hands and took it to a stealership. I decided to take a hose to try to pinpoint this hissing sound. It still was coming around the EGR but the erratic idle makes it hard to distinguish it especially when the fans come on. Getting Close Though.

WEEK 8. Finally found the source of my erratic idle. There was a big air leak coming from when the intake manifold meets the head. It is close to the injector to the 4th cylinder. Not an easy job.

So here is my question. I have seen the thread by "Cokinut" and other who have swapped their intake manifold. I only want to replace the gasket. Is there an easy way to do this without taking everything apart? Is there another solution someone has done successfully?

Thanks for reading.

i know its an old post but this is what i was looking for.
there are three wholes on the throttle body and only 2 on the valve is that valve off from the same place or im i missing something here

[wed3k]

IACV is on the left, 2 bolt.
FITV is on right, 3 bolt.

[HondaFan81]

Since the IM has studs/nuts for fasteners, the correct way is to remove it completely and then clean both the head and IM side of the old gasket material. Then, install the new gasket (whichever type OEM paper or phenolic type). Retorque all nuts evenly snug by hand or 16 lb-ft.

Not cleaning the old gasket material off, as the paper stuff does not come off easy but in pieces, is cause for future leaks and potentially not even fixing the problem. Bottomline, if you have a leak from this IM gasket after you finish the job, you'll problem will remain and you have wasted time & money.

If you wanted to upgrade to a F22a6 or H23 IM, now is the time. You'll be in there anyhow. You can choose for IAB control (need PT6 ECU) or not. If you get the PT6 ECU, then get the F22a6 camshaft as well.

[93accdpj]

You will find it hard to get to some of the IM bolts and the support brace bolt with the plenum installed. It takes a few more gaskets, but less Tylenol to separate the plenum before removing the runners. Also as hondafan said you really need to get things open enough to see that you have all the old gasket removed from both surfaces. There is a red rubbrized ring around a water jacket that will cause serious probs if you dont get a good seal there.

[Shehzada]

HondaFan81,

Thats exactly what I and CPMike ended up doing. Every trace of the old gasket was removed. The hardest part was actually removing the IM since 1 or 2 bolts must be removed from underneath. The repair is still strong!