car "jolts" when turning on a/c [Archive] - Drive Accord Honda Forums

: car "jolts" when turning on a/c


Sig86 CM8
06-02-2008, 06:56 AM
it's done this since i got it and i figured i would ask if this is normal or if something is messed up.

if i am going slow and go to turn on my a/c, you can feel the car 'jolt' when the compressor kicks on for the a/c and obviously the a/c isn't cold right away, takes a few minutes to finally get ice cold.

if i'm at a higher rate of speed (45+mph), it does it still, but it's a lot smaller than when going at a slower speed since i'm going faster

the only real time it scared me is when i was pulling in to park at home and doing less than 10mph, turned it on so when i remote start it the next day it would be cold. the car jolted and you could hear it make like a clanking sound outside the car.

is this normal? or do i need to have it checked out before my freaking a/c stops working in this hot south fl weather?

Accordlover
06-02-2008, 07:02 AM
By jolt do you just mean a prominent vibration?

Honda's have very noisy A/C compressors. They tick/click/clunk on and off and the idle is really effected by A/C operation. The compressor should in no way effect the car's movement, so if that's whats happeneing, then you should have it looked at.

However, it sounds like you might ust not familiar with Honda A/C systems; they're not the best.

Sig86 CM8
06-02-2008, 07:09 AM
i'm due for an oil change soon so i'll have them check out the a/c then just to be safe

princess
06-02-2008, 07:35 AM
The car raises the RPM when the AC comes on. If the idle is too high, the possibly it could feel like a "jolt" when it happens. Usually on the newer ones, it the idle is too high you'd get a code though.

Sig86 CM8
06-02-2008, 07:45 AM
i'll have to check later and see if the RPM raises when i turn the a/c on

andysinnh
06-02-2008, 08:16 AM
this is true with all Hondas I've owned, even the 90's vintage Acuras - the Honda A/C kicks in really "abruptly", and can cause a "surge" feel as the rpm's kick up - and the fact you notice it at slower speeds (and lower rpm's likely) is very typical. Some are more abrupt than others. At idle, sometimes you can hear the compressor make a "clunk" as the clutch engages. It's especially true for the first time the compressor kicks in for a while (like when you put the defroster on from a vent position).

andy

WolfpackBill
06-02-2008, 08:40 AM
Very very true. All Hondas do that. All 3 of our Hondas ('98 Accord EX-V6, '05 Odyssey, and mine) do that.

hwilljr88
06-02-2008, 08:57 AM
I concur...All of tha honda's in our family did that. '86 Civic, '91 Civic, '94 Accord, '03 Oddy, '06 CR-V, and tha '08 Accord. All have a lil jolt...nothing out of the ordinary from a Honda

03LXV6
06-02-2008, 10:26 AM
I get the some "jolt" when stopped at a light. I find that it happens because the RPMs increase and I'm not pressing the brake all the way in so the extra RPMs will give it enough power to roll a bit.

Fredsvt
06-02-2008, 04:47 PM
The "jolt" , "thump" or "bang" the compressor makes on initial start after the a/c has been off for a long while is the compressor actually not turning easily at first. Actually it can be physically locked up, depending on where the compressor is in its cycle.

The compressor is low mounted, obviously, when it sits off for anything longer than a few hours, the refrigerant oil pools in the compressor. Since oil is not compressible the engine has to work extra hard to clear the oil out and send it back into the lines.

On my 6 speed, I always make sure to turn on the a/c when the rpm is below 2k if possible. I've turned it on a couple of times at around 2500 to 3k and the belt will squeal madly until the compressor is able to turn.

Accords aren't the only ones that are subject to this, nearly all cars/trucks with low mount compressors with lines that drop from much higher, have oil slugging problems.

daavo
06-02-2008, 05:36 PM
Both of my 7th gens have had the same issue. Sometimes if I engage it while I'm driving it actually sounds like I've hit something on the road. It would be nice if Honda could figure out a way for the clutch to engage in a more refined way. In other four cylinder cars I've rented recently you can hardly tell when the a/c is engaged.

The compressor is low mounted, obviously, when it sits off for anything longer than a few hours, the refrigerant oil pools in the compressor. Since oil is not compressible the engine has to work extra hard to clear the oil out and send it back into the lines.

On my 6 speed, I always make sure to turn on the a/c when the rpm is below 2k if possible. I've turned it on a couple of times at around 2500 to 3k and the belt will squeal madly until the compressor is able to turn.

I try to engage while I'm at a stop but I've been working on my hypermiling techniques. A/c is my engine braking while slowing down for offramps and stops :D.

psyshack
06-02-2008, 06:34 PM
Our Accord does not give a jolt, pop, bang. And it sure does not make clanking noise's. Its a little click and you can feel the draw.

The poster makes it sound like its a old Chrysler Air Temp V-Twin compressor turning on. A old pan head Harley without spark plugs of a A/C compressor if there ever was one.

Have them look at it. Should be a near seamless event. IMHO.

Sig86 CM8
06-02-2008, 07:25 PM
psyshack - i'm not exaggerating. i've had plenty of different POS cars before this one to know what a jolt is compared to a small click

andysinnh
06-03-2008, 07:13 AM
psyshack - i'm not exaggerating. i've had plenty of different POS cars before this one to know what a jolt is compared to a small click

If I compare the A/C compressor engagement between my Pilot and Accord, versus the Freestyle and Montego - it's like night and day. Honda is loud, and perhaps Psy's tolerance for engagement is greater than normal. Don't sweat what you're observing - it's normal.

andy

psyshack
06-03-2008, 10:06 AM
If I compare the A/C compressor engagement between my Pilot and Accord, versus the Freestyle and Montego - it's like night and day. Honda is loud, and perhaps Psy's tolerance for engagement is greater than normal. Don't sweat what you're observing - it's normal.

andy

Andy... I swear our Accord A/C engaugement is smooth as silk. A click then the draw or the compressor. My Civic was the same way and so is my Mazda. Just a click of the clutch enrgizing and then the slight draw on the engines. Nothing dramtic at all. Does not matter what the rpm is. The Ranger is the worse of our cars. And its just because the magntic drive is louder and the compressor is a York POS.

If mine start clattering and making undue noise. I will look into it. Click > slight hum. Thats it.

RTexasF
06-03-2008, 10:40 AM
Mine also clunks when engaging and makes the engine shudder slightly at idle. It blows cold and does so quickly so I'm happy with it. With the RAV4 you have no idea if the A/C is on or not, no difference is felt whatsoever, and no sound is heard at all.

Fredsvt
06-03-2008, 03:31 PM
Psy, how often do you use the a/c?

If you use it more often, or like many, just set it on auto all the time, the oil rarely gets to settle in the compressor.
I've had Odyssey, Pilot, Accord V6 all do it.

I constantly get questioned on it from one customer who thinks it'll magically disappear.

When I use my car on long trips it rarely does it, even after sitting overnight, same goes for when the weather gets crappy (hot, humid) and I use the a/c a lot it won't do it. Let the a/c sit off for longer than a day or so, it'll do it.

psyshack
06-03-2008, 04:33 PM
Psy, how often do you use the a/c?

If you use it more often, or like many, just set it on auto all the time, the oil rarely gets to settle in the compressor.
I've had Odyssey, Pilot, Accord V6 all do it.

I constantly get questioned on it from one customer who thinks it'll magically disappear.

When I use my car on long trips it rarely does it, even after sitting overnight, same goes for when the weather gets crappy (hot, humid) and I use the a/c a lot it won't do it. Let the a/c sit off for longer than a day or so, it'll do it.

I don't use it much. MPG drivers over all stay away from it. :) But it does get used. It can go at times several weeks without being used. I would be real pissed if my Accords A/C came on like a 30 year old mopar.

Fredsvt
06-03-2008, 04:42 PM
I think I'd rather have it come on like a 30 year old mopar, versus a newer mopar. It comes on!
The newer one usually don't work as the evaporator cores tend to break and leak out. Or the compressors lunch themselves. I haven't seen any late model Chrysler product NOT need an evaporator sometime in it's life, however short they may be.