BeaterHonda

Hello,

I have the up and down idle problem and have tried every fix imaginable and its still there. My original post is this one:

https://www.honda-acura.net/forums/s...d.php?t=258815

I put in a used MAP sensor and the problem is still there.

So I want to try checking/lowering my base idle to see if it goes away... what is the proper procedure for this? I know its supposed to be done with the IACV unplugged, but do i do it when the car is warm or cold? Do i turn the screw that is the mechanical stop for the throttle blade, or is there another adjustment I should be making? Is there any other connectors i need to jumper? Finally do i have to reset the ECM by removing the brown fuse? Do i let it run after to let the ECM "learn" the new idle?

I already did a search but found lots of different answers.

THanks!

gulfview

SETTING IDLE SPEED

1. warm up engine fully
2. unplug idle air control valve and run engine
3. find idle screw -- usually on the right (passenger) side of the throttle body -- the size if a dime
4. turn IN to reduce speed; turn OUT to increase it -- use correct data -- around 500-600 rpm -- look it up
5. turn off engine and plug IACV back in
6. remove brown 7.5 amp fuse, the closest to the driver in the fuse box under the hood -- for one minute -- resets computer -- the idle speed should move up to 700-800 rpm -- and your car will love the correct speed
7. With each day, your car should run better

For more info about your idling problem, do a search under UP AND DOWN IDLE

Good luck!

BeaterHonda

Thanks for this info!

I followed all the steps and it seems that the base idle with the IACV disconnected does not want to go below 1000 RPMs. I turned the adjustment screw all the way in until it wouldnt go anymore, and the upper port in the throttle body is sucking very little air. but the base idle doesnt go below this.

I checked all my vaccuum lines and everything is on and tight and no apparent leaks... but when i put my hand over the entire throttle body opening the engine doesnt die. Could this mean there's still a leak somewhere?

Right now the up and down idle seems to be a lot better though... the car is idling at about 1000 rpms when warm, but still occasionally does the up and down. will this straighten itself out with time too?

Any thoughts/ ideas?

Thanks again man!

gulfview

Yes, you could have an air leak. Places to check -- the gasket beween the throttle body and the air plenum and the air plenum and the intake manifold, and finally, between the intake manifold and the block.

You could test for an air leak with an unlit propane torch or a can of starting fluid -- with a running engine. Release gas or spray around the suspected areas and when and where the engine speeds up, that is the location of the leak. Many auto stores (Autozone) may carry the gaskets you would need.

Best wishes and keep up the good work!

BeaterHonda

Hey Gulf,

Thanks again for your input! tomorrow after work i'll take the upper intake off, and clean all the gasket surfaces and put some RTV between the intake and all the gasket surfaces (IACV, TB, FITV, and upper to lower intake) to try to eliminate the leak...

I did a full tune up a few weeks ago, and i did have to remove the upper intake to change my heater core hoses, and i reused the old gasket so maybe something was disturbed... also i took the throttle body off to clean it so maybe that gasket might have a leak.

I tried the propane trick and it didnt detect anything, but then again i could only use it to get to about 40% of the flange surfaces. After I regasket all the surfaces I could plug the vaccuum lines to the intake coming off the PCV and the brake booster to isolate the problem, then maybe see if there is still a leak...

Any thoughts on this idea?

Thanks!

gulfview

You are on the right track! It pays to use good gaskets. Sounds like you are a hard worker!!!

BeaterHonda

So I took everything apart and after cleaning and RTV'ing all the surfaces i let it sit overnight for the sealer to set.

Today i started the car, and put my hand over the throttle body to see if i still had any vaccuum leaks, and sure enough the engine continued to run at about 150-200 RPMS. So i capped off the brake booster and the PCV and did the test again with covering the TB... engine still ran!!! But i could hear the leak this time... after feeling around i found out the throttle body gasket was leaking air from the bottom!!

The gasket i used was a store bought Felpro pre cut one... it didnt quite cover the entire TB so i was wary but choices were limited. So after i found the leak i went to Autozone, bought gasket paper stock and made my own gasket. After installing it, the idle came way down to where it was supposed to, and my UP AND DOWN IDLE PROBLEM WENT AWAY!!! I set my base idle per Gulf's instructions, and now the car runs like a dream!!!

So to summarize, anyone who recently did any work to the engine and then resulted in a surging or bouncing idle, check for vaccuum leaks first, its the cheapest fix and and the least amount of work!!! Covering the TB and seeing if the engine still runs is a pretty effective and easy thing to do, and then after that check out the other components like the FITV and IACV, then sensors, probably in that order is the most effective way to eliminate the problem.

Gulf, thanks again for your help and input!!! As far as being a hardworker, it helps to have an understanding wife who lets you play in the garage that much! Thanks to everyone else who helped out too!

gulfview

I am really happy for you BH! You have done really well!