98 Lx A/T 162k stock
I followed the guide for y7 to y8 IM swap found over on d-series site.
Used IM from a 98 Ex A/T and fuel rail. On y7 injectors. Hook everything up. Bled the coolant. Now my car idle at 900-1000rpm in normal working temp. Does that seem higher then normal?
When i first start the car the idle surge up and down. I took the iacv off and clean it.
Now it wont idle less then 900rpms.
Bled the coolant until fan kick on twice. Saw lots of bubbles. Waited til clear of bubbles.

Drive fine but idle is def not normal?

I also had done the valve lash adjustments during the IM swap. Used 0.008 for intake and 0.010 for exhaust. I dont know if that affect idle ? Im thinking not. But I'm not sure.

I reused the y7 tb gasket since it was in good shape. But ordered a new one. Will pick up in the AM.

No vac leak. All sensors,map, tps, iacv, evap, pcv.. All plugged up correctly. I labeled, with masking tape, each harness before removing.

I dont kniw what to do next.
Any suggestions is greatly appreciated.

 

How i check for vacuum leak. With intake arm off. I start the car, then cover up the tb with my hand. The car die immediately.. Then i start it again and use carb cleaner, spraying the vacuum hose and intake manigold gasket. No change in idle.

 

Have you reset your base idle per the service manual?

 

I did not. Because the guide never mentioned the need for it. Since I was using the stock y7 tb and parts. But if I need to, I will search to find the procedure.
I did unhook battery for a long time before hooking it back up. To clear and reset everything. I don't know if that is the something?

 

You were close.
picture_4760.jpg Photo by RonJ_HT | Photobucket

Try using this and report back.

 

I dont have to mess with the TPS do i? Because i dont know anything about that. I will try the procedure tonight and report back.
Thank u for the link

 

CEL codes?

 

There was a p0505. But it didnt come back after clearing it. Did that after i cleaned the iac.

 

I always reset base idle when the manifold comes off, especially if i am changing the style like you did. its not the same parts and the ecu cannot see that change it is trying to base idle on what was on the car...

 

So if i followed the link Omega posted, i will be ok?
I did not have time this evening to do that. Will have to wait til tomorrow night after work.
If there is a different way to reset base idle, can you please link me to it?

Thank u

 

I followed the procedure. I could only turn the idle screw clockwise 1/2 turn plus another 1/4 turn then it stopped. Which mean its screwed in all the way clockwise already. Turning it clockwise lowered the idle a little but not much. Some reason tonight it wont idle around 900 anymore but stayed at 1000+... Turning it counter clockwise raised the idle. Then the CEL came on. P0505..then idle starts to get jumpy, fluctuating. Like before. I will have to buy another iacv to test further..

Already put in new tb gasket. Made no different.

 

You have a vacuum leak somewhere. Find a friend who smokes cigars. Or a friend who vapes and brags about big clouds. Or go rent/buy a smoke machine from a party store. Start the car, use the smoke, follow the smoke, find the leak.

 

Let's say there is a leak. With the car running. I put my hand over the tb and the car stall and die. would it still be running if there is a leak? I'm asking because I do not know and would like to find out.

No friends that smoke. Rent option is 2hrs away. May have to wait.

 

You need an accurate external tachometer to measure and adjust the idle speed.

 

I've seen two different designed gaskets for egr and non egr and had similar issue. Spray some brake clean at the top of the intake where it meets the head by the injectors. If it stalls or chugs you have the wrong gasket.

 

I am using an ultragauge. Similar to a scangauge which uses obd2 port to collect and report data. That's how I saw the cel code when it pop up. My ultragauge does does rpm values as I adjust the idle screw. But it won't turn anymore as it maxed out with only 1/2 turn + another 1/4 turn (clockwise)..

 

My new IM gasket is the exact size and look of the stock one. I line it both up on and off the head and they matched exactly.
I did spray carb cleaner around the edge where the gasket is. No change in idle.

 

As it idle, i unplug the iac to see what it does and the idle started fluctuating. Up and down idle. Then a p1509 pop up. Plug itback in and the idle surge slightly. What does that mean?
If i plugged the lower port inside the TB idle go down, not a lot but does go down. What does that mean?

 

Check on this video....




Really helps to understand a lot better how it works.... may help... its a 25 min video so take your time.....

 

The Fast idle valve FITV its the one help the engine to get warm goes around 1.5k to 2k rpms , after reach the 100cc (around) goes to the regular idle rpm (0.7 to 1k rpm) as my understanding is the IACV the one keep the low idle.... And if you have any codes make sure to take care of them first.


Sounds like repost, but hope help you.

 

No FITV on my d16y7. So nothing i can do there.
Im gonna try the smoke leak thing later. I just dont think there is a leak anywhere. But will check anyway.

 

 

UPDATE:
problem solved. Idle is now back to normal 700-800rpm at idle..
I don't know how but here is what I did.
1. Use cigar for smoke leak check. No leak out of vacuum hoses. BUT, notice very small amount of smoke coming out the tb rotor where the coil spring is.


No leak anywhere else.
I then uninstall the tb cable rotor, inspect parts, reinstall. Making sure nothing catches or torque the screw too much.

2. I doubled up the tb gasket, old and new as one. Overkill, I know. But doesnt hurt. No leak.

3. Remove pcv, swap in one from my other Honda.

4. Check IAC, TPS, MAP harness for cut, shear, or fray. No issue there.

5. Start the car, let idle, turn the idle screw clockwise 1/2 turn. Let it idle.. Turn counterclockwise back to original marking I made yesterday.. Turn car off.. Button everything back up. Check and triple check everything over. Making sure northing is out place..

6. Pull 7.5amp Radio fuse. To reset ecu.. Wait couple mins.. Clean up..put fuse back on.

7. Start car up.
Idle sit at 1000rpm for bit then drop slowly to 750+/-50...
Perfect.
Let idle for awhile and that's where it stays. No more high idle..
No more cel..

*fingers crossed*

2 things I feel may had contributed to the issue.
1. Tb rotor swap. Y8 rotor on y7 tb. During swap, I may have screwed up, overtightened screw and/or coil spring. Causing a leak.
2. Pcv may have gone bad, coincidence.

I will update more if things changes.

For now. Thank you all for your help.
I am satisfy with this fix..