Hello! 89 Accord engine vibrate, idle high in park/neutral.

[RamThis]

I have an 89 2.0L Auto, 2bbl carbed Accord LX. Here's what Ive done already:

Rebuilt Carb
Fixed leaking freeze plugs under intake
New intake Gasket
New Timing Belt
New Acc. Belts
New plugs, wires, cap, rotor.
New motor mounts
New Radiator and Thermostat
New Air filter and fuel filters
Fixed AC refrigerant leak at compressor
Converted to 134A with fresh PAG oil
New temp sending unit
Half the vacuum hoses are new around the carb (about twenty of them)
New fuel line.
Timing adjusted per instructions (15* at idle in gear @750 RPM)

The engine vibrates under load, enough so that when it hits about 2500 RPM
on the highway, it rattles your keychain hanging from the column, and
something under the dash rattles a bit, but only when it starts this harder
shake. You can feel the shake some when you have it in park and rev it,
once it hits 2500, you feel the vibration.

It also seems to shake at idle too in gear. If I let the RPM go down to 750
like its supposed to be set, it shakes, especially when the AC turns on. I
have to idle it up to 1000 RPM in gear to stop the shake.

It also does not want to idle down in neutral, Seems there should be some
sort of vacuum controlled idle when put in gear, but it doesnt that I can
tell. There is one vacuum controlled device that I got working that raises
the idle when the AC compressor kicks in, but the one on the other side of
the carb does not seem to do anything. Im assuming this is either for the
Cruise control, or something to idle up when you put the car in gear. My
cheap ass Haynes manual is worthless for telling me how to adjust the idle.


Is this supposed to raise the idle when in gear?
First pic is of the actuator itself, passenger front side of the carb.


This pic is whats behind it, the rod coming out of the back of it, facing
toward the firewall. It is plumbed into some little black canister on the
passenger side fender, and teed into some electronic solenoid, and
also goes up to some other doohickey on the passenger side fender.
I measured the vac signal on the line going into the actuator and only
get a slow rise to about 10". The car at idle gets about 17" of vacuum
on the tree. I can get more detailed pics if needed to help diagnose....



Thank you in advance for any help you guys can give me on these two problems Im having.....

[lackej1971]

You may have tried this already, but it's worth a shot. #1, Remove the fuel line from the CARBEURETOR Stem BEFORE starting it at all. Then put the hose into a glass or clear jar. Then turn the key to the stage JUST BEFORE IGNITION about 4 - 5 times. Now look in your cup. If it is dirty or has water in it, get some fuel drier and add it to your fuel tank.

#2 Have you checked/adjusted the float level in the sight glass on the side of your carb? It should be right in the middle of the little sight glass. It's sorta hard to see and you may have to remove the sight glass (2 screws) and clean it off and reinstall it. If you don't know how to adjust the float level, just look it up on this site and you will see it in the How To section.

#3 Have you checked and set the gap on your valves? THAT made a huge difference in the vibration on my car. Oh Yeah! It wa doing exactly what yours is doing now. Now it is smooth as a whistle. It's also in the How To Section. (I love this site!!!! They have everything I need almost)

My car did what you said and after I did these things it just hums now.

James

[lackej1971]

OH, I forgot to ask. Did you set the engine timing also? It really makes a BIG difference in the shaking also. There is a very exact way of doing it and you can find it on here also. Do exactly like it says and you can do it yourself. The results are great.

James

[RamThis]

The fuel system I cleaned out before I put the rebuilt carb back on, so I know there is no water or debris in there, also replaced fuel lines and filters and flushed out the gas tank with some extra clean gas.

I have set the float level via the sight glass.

I have not yet set the rockers. I guess I need to check them. They do make a little noise if you listen really carefully up close to the valve cover.

I have set the timing, its very easy. 750 rpm in gear with the vac advance unhooked and plugged, set to 15*, tighten the dist down, hook up the vac advance again, good to go.

Im going to replace the front and rear motor mounts as well. Im thinking if they look half as bad as the strut bushings and the driver side mount, this is probably where MOST of the vibration is coming from lol.

[AccordOwner]

If you haven't found out by now, the Accord auto with a/c has a dual diaphragm gizmo on the driver's side of the carb. The screw on front is for adjusting the idle while in gear, and on the back of the actuator is a knurled knob covered with a rubber cap that is used to adjust for the a/c while in idle. It will have two(2) vacuum hoses to it. Cheers. By the way, if you turn the screw too much, it affects the over all idle, also. That is a no-no.

[RamThis]

Hmm, that makes sense to me. I didnt understand really why it had two vac lines. I have the rear screw, the one that is in the body of the actuator, screwed all the way in. Otherwise, it doesnt seem to do anything other than when I turn on the AC. I have it set so that when the AC comes on, it pulls that rod back and the adjustment on that end, the part facing the front of the car, steadies the idle so you almost dont even feel the rpm change when the AC engages.

How do I adjust it to control the idle in gear? Any tips would help. I have the other controller on the passenger side of the carb set right as far as the book says. But, this idle still seems odd to me, though Ive been told its right, so Im still confused.

I backed off the front screw on the AC idle boost rod, and the Throttle Controller. I adjusted the idle using the throttle stop screw back to about 700 rpm. I then put the car in gear, and used the Throttle Controller screw to idle it up to about 800 RPM. Then I turned on the AC, and used the AC boost screw, the one facing the front of the car on the driver side, to run the idle back up to 800 again. Then, when the AC is off, the acuator releases, the load is back off the engine, and the in gear idle stays at 800. I put the car in P, and it jumps to 1100 RPM.

Is this right?