silver accord

Hello, I have read many post in the stickies about Idle surging issues and have removed an thoroughly cleaned the throttle body and removed the rotary air valve sensor and cleaned it on the back of the TB. Purged air several times from the coolant vent. Removed the fuse to reset the ECU several times. The surging issue is still about 1000 -2000 RPMs constantly. I have looked over the all vaccum hoses and can not find any leaks.Can anyone tell me what I can check or replace to correct this problem? Thanks

slomofo

iTrader: (1)

Check for vacuum leaks.

silver accord

Thanks for the quick reply Slomofo, I checked all vacuum hoses I can see from above engine and below.... I see one coming off the bottom of the TB and runs down to the chasis area and i cant trace it , but all others seem to be very snug. Anything else ,,,I'm sure that I'm overlooking the obvious? Thanks in advance.

silver accord

I cranked the engine this morning (30 deg. outside) and the rpms were steady at 1400 rpms for about 5 min then started surging again 1000 -2000 rpms. Then finally threw "check engine light" and rpms bouncing 1000-1200 and idling rough. Any ideas that on what I can check now to diagnose?
Thanks.

GhostAccord

Use an OBD2 scanner and retrieve the check engine light code from your ECU. That will probably help you find what is wrong. At least it should point you in the right direction.

Did you use a new gasket on the throttle body when you did the tb cleaning?

When checking for vacuum leaks it is best to use an aerosol can of carb/throttle body cleaner. Lightly spray the hoses and any gaskets on the intake manifold with the carb cleaner. If the idle drops while spraying that is an indication of a leak.

silver accord

I did not use a new gasket on the TB because the one that splits the upper and lower halves was metal and was not damaged when I removed it... do you think I should have? And the O ring gasket for the Rotary valve was in good shape also.
I have got a OBD2 reader today and will check when I get home.today.
I also read on a previous sticky that someone have to have an adapter that hooked to the radiator to flush the air bubble out.... that it would not come out by the bleed screw. This person had the same symptoms I am having. Have you heard of this also?
Thanks for any input you guys can give me!

silver accord

YESSSSS.... I found the problem, There was a stuborn A** air pocket in the TB/intake somewhere!! I was getting CEL = P0505 = IAC Valve system fault.

Anyway here is what i had to do for informational purposes...
If you attempt... do so at your own risk...
1)I jacked the front of the car up as high as possible put jack stands under it.
2) I filled the radiator with coolant as full as possible and put cap on rad.
3) I pulled the coolant overflow tank out of it slot and set it upright , higher than the radiator.
4) I held the engine idle about 3000 rpms and watched the overflow tank for bubbles and turned the vent screw on the engine to help bleed air out of system.
5) It took about 3 times of reseting the CEL and doing the engine rev routine before I got all the bubbles out and the idle surge is now gone .
6) Once the cooling fans came on and after surge was gone , I turned the engine off and pulled the fuse on the ECU to reset.
The engine runs perfect now!!!

Thanks to Slomofo and Ghost Accord for their help.

nus_dogg

Nice!!