m1ndless

Latley, I have noticed when I am at a redlight or stopped, but in drive, and my A/C is on, my car shakes/vibrates really bad, its quick, but it is only happening when I have my AC on, when my AC is off, no shakes or vibrations..

Any Idea?

bowser_cd5

i had that problem...for me it was the front engine mount, it was shot. how many miles are on your car?

dwayne1413

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bowser_cd5 &raquo;</TD></TR><TR><TD CLASS="quote">i had that problem...for me it was the front engine mount, it was shot. how many miles are on your car?</TD></TR></TABLE>

sounds about right. check your engine mounts all around. if you have never replaced them yourself depending on how long you have had the car you should definitely check those out first.

JimBlake

4-cylinder auto-tranny cars have a vacuum-operated rear engine mount. It's supposed to make itself softer when idling in gear. Maybe that's messed up?

What's the idle RPM under that condition of in-gear when AC cycles?

m1ndless

Its around 1000-1200 rpms at idle in drive with AC on, in park with AC on its about 800. I will check out the motor mounts.

97blackaccorder

I'm having the same issue. I've got a 97 Accord LX 2.2 non-VTEC 4 banger.

I've had a rough idle for a couple of months now and it seems to get much worse when I turn on the A/C. It doesn't stall but it is very shakey for about 10 sec and then smoothes out, but stays a rougher idle than without the A/C.

Things I've done so far to address this...
- replaced PCV valve
- injectors/fuel system cleaned
- motor mounts checked out and look fine
- new plugs, cap, wires

what would you do next?

sony224422

the car is going to shake a little, its running a belt driven compressor. You could make sure the compressor is functioning 100%

ezol

Mine is the same way, any of you guys experience idle shake in the winter time when the car is very cold? If so will changing engine mounts help? I have about 180k on my engine.

m1ndless

I checked out my compressor today, and I think that may be the cause of the problem, at least I hope.

I am driving from Phoenix to San Diego on sunday.. I hope my car will be alright for the trip.. or is it a bad idea?

sony224422

why do you think your compressor is bad?

m1ndless

Since its only happening when my AC is on, I turned my AC on, popped my hood, and I think from what I could tell, my compressor is making the vibration, just by eyeing it though I made that assumption. .

JimBlake

Maybe your AC compressor has a loose bracket allowing it to vibrate? It should be mounted very solid.

Also look for pulleys that are bent or out-of-round.

I don't want to assume too much about other years that I don't own, but 1000-1200 rpm seems too high for idle speed. I thought when the compressor clutches in the engine control would just compensate enough to hold the same idle - not raise it.

JimBlake

Whoever has an auto-tranny, crawl under & look for the vacuum lines going to the rear engine mount. Back between the engine & the firewall. There should be a solenoid valve in the vacuum line somewhere. Unplug the wire. I don't know if it's easier to reach from below or above.

Now when it's in gear the vibration should be worse because the mount can't make itself softer. That's basically how you test the vacuum-controlled mount.

sony224422

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JimBlake &raquo;</TD></TR><TR><TD CLASS="quote">Maybe your AC compressor has a loose bracket allowing it to vibrate? It should be mounted very solid.

Also look for pulleys that are bent or out-of-round.

I don't want to assume too much about other years that I don't own, but 1000-1200 rpm seems too high for idle speed. I thought when the compressor clutches in the engine control would just compensate enough to hold the same idle - not raise it.
</TD></TR></TABLE>

its def too high idle for my 96. i think i idle at like 800 and dip a little lower with the a/c on.

m1ndless

I must have been thinking wrong, it idels around 800-900, its a little high, but its 110 out here, very freakin hot.