h22god

This has been an on going issue and I think I have it narrowed down to the brake
booster. .. but tell me what you think. This issue was happening on my old h22 and now my fully built h23vtec. When its cold out it will idle perfect until warmed up and for the first few minutes while warming up if I hit the brakes hard it will idle like a baby. But once warm it hass ruff idle none stop unless a light turns red and I have to get on the brakes hard. So while the car is slowing the idle is perfect but as soon as the car completely stops the ruff idle is back.

It cant be the engine because everything is brand new besides the distributor and brake booster. And this was happening on my old motor and now this new one. Has anyone experienced these symptoms and it was the brake booster? I'm thinking of buying one but I dont want todo it if its not the booster. Iacv is clean and working and shut off in the computer. Fitv, has a omni 70mm on it now. Vacuum caps all around. I think the only vacuum line there is on it is for the fpr. And it's good. I would love the car so much more if it would idle like it does when I'm hitting the brakes hard.

TomCat39

Not sure if this will be helpful for you, but when you hit the brakes it uses vacuum to "assist" and the ECU naturally raises the idle.

You can easily test this by idling and pumping your brakes, if your car is like mine the idle jumps up until I stop pumping.

Sounds like you have an aftermarket FITV and I would guess it's not quite calibrated for your setup.

civicsiguy21

Three things that almost always lead to a idle problem fitv, iacv or a bad vacum. The fitv and iacv get gummy and need cleaned or gaskets need replaced. It sound to me like a vacum problem.

TomCat39

Only problem with that idea is he only has one vacuum line, no IACV and he's checked the line and I'm sure all the caps.

That really only leaves the aftermarket FITV. *shrug*

slowhatchcali

Disconnect the vacuum like from the manifold to the booster and cap it. If it idles fine it's the booster. Simple enough.

carlos8

First Omni power NOT make 70mm FITV's they made 70mm Throttle bodies. with that being said the majority of the times when you use aftermarket throttle the FITV it's eliminated cause they not have provision to install it, like the Omni.

For check your booster, Plug it and see for differences in the engine or do the right form and perform a vacuum test.

What intake manifold you have, if it's stock sometimes the gasket from bigger throttles don't cover perfectly the IACV division creating, high and surging idle situation.

h22god

Yes I figured everyone would know when I said omni 70mm I wasn't talking about a 70mm Fitv , and would know they are deleted on the omni throttle bodies. My bad. I have already used a pair of coolant/hose clamps while the car was running and there was no difference. .. and the other guy is correct I only have one vacuum line other then the booster line. And that's the fpr . The only other thing I can think of is the distributor because everything is brand new and it does it just like before on the old motor. Only thing that is the same is the distributor and brake booster. It has a omni 70mm tb with the gasket that came with it brand new and perfect. And a skunk2 im with a zerg im gasket 500cc densos and oem rail and fpr .

I guess I could go buy a vacuum tester just to see what I can come up with compression test came back at 270 a cross the board and leakdown came back excellent to. Im wondering if its the distributor. ..

h22god

And the idle when cold fluctuates alot when cold when I pump the brakes and not so much when warm.

carlos8

Follow this link to test your distributor, Good luck!!!

https://honda-tech.com/forums/honda-accord-1990-2002-2/distributor-resistance-ranges-troubleshooting-crank-sensor-3180944/