89 Honda Accord idle problem

I have an 89 Honda Accord LXI (fuel-injected), 5-speed, with 380,000 miles (and still runs great). For the past year or so, it's had an idle problem that the dealer hasn't figured out. The idle speed has been adjusted with no success. The idle control valve has been replaced with no success. The vehicle idles so low that it causes the whole car to vibrate. It's worse with the a/c on. If you increase the engine speed just a tiny bit the vibration goes away.

Also (and I'm not sure if this is part of the same problem or a separate problem), when you turn on the headlights, turn on the a/c, put a window up/down, apply the brakes, or turn the steering wheel (the most noticeable), the car idles down. It idles so low that you think it's getting ready to stall, but it never does.

Any ideas?

 

Torn Engine mount........

 

Those have been checked and they seem to be okay, but thanks for the idea.

 

Everything you've described has to do with the low idle speed.

Buy a cheap vacuum gauge and hook it up to manifold vacuum and see what you get. If its low (under 18) = timing belt, although it can be a few other things. If you have a pulse in the reading = leaking intake.

When the idle was adjusted were they able to speed it up? A lot of dealers simply write off a car of that age and mileage as non-serviceable.

 

The timing belt was changed within the last year or so (had to replace a leaking oil pump and they went ahead and changed the timing belt while they had it all apart). The idle speed can be adjusted higher but it resets itself/compensates automatically (or something to that effect). I'll try the vacuum test. It's possible that the dealer already checked that but if so I don't recall it ever being mentioned.

After 19 years, I figure those guys ought to know my car pretty well by now. Some of them have worked on it from day 1. Thanks.

 

Sounds like a bad ground to me. Its a ***** but go through your car and check out all your ground points and check for corrosion, poor connections, pinched wiring. Hit up my website download ur self a Factory service manual and that'll show you where all your ground points are located
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