04 6spd ~90k.

Seems that recently anytime I am idling and the climate control cycles on, for the first 5-10 seconds, the car vibrates noticeably and the rpms increase from 700 to ~750. This goes away after about 10 seconds.

At first I assumed this was the AC compressor (which kicks on cold or hot weather), but I just had the entire AC system replaced w/ goodwill warranty after it crapped out last summer...so I was figuring a "new" compressor wouldnt cause this.

is the AC compressor the only possible cause, or what else might put down a ton of resistance on startup of the climate control system?

If i turn CC off, it stops immediately.

At this point, this is the only problem on the car that keeps me from thinking it will last for 200k+ miles...its really been a great car, but this has me slightly nervous.

 

what was replace?

I had this same issue and all i did was replace the heater core and did a ac refill and it solved the problem. also at that mileage, if you havent change your plugs .. i recomend doing them. as these are the two step i took in resolving said issue

 

I'm having the same problem. The other TSX I test drove had the same problem, so it must be a common thing. How easy is it to replace the heater core?

 

it's easy. only problem is that it's against the law in most state to do it at home. need a certified a/c tech to do it bc of releasing the ac fluid. basically, once it's fully drained out. you'll need to take the front bumper off. then take off a few 10mm nut and pull the hose off the heater core and pull it out. willl need to remove the radiator fan and top radiator brackets so you can have room to work with.

there's two point on the heater core that there's a metal hose connect to. just remove those and you're good. then put in the new heater core and reassemble. recharge your ac then thats it.

for me, the shaking was due to the dryer (sorta like a filter) found in a tube that's built into the heater core have clogged up. once you have your old heater core apart, it's easily removable by removing the bottom cap and pull the dryer out. it's a bag. you'll notice one end is white and the other black.

the bag is a filter to keep moisture and dirt out of the ac system. soo .. if the filter is black .. something is causing it. which if you do a search .. mostlikely due to the ac compressor.

to confirm issue, have a tech check the pressure of the ac. high pressure and low pressure. the low pressure (i think it's the low pressure , from what i remember) dial will be eratic while the high side will be steady.

again .. you'll need to drain and fill your ac system if you do this. before you do this. have it diagnosed.

 

from my understanding. this is the begining of a long process of problem if not taken care of.

if the dryer is clogged, the ac system will build ton of pressure which will over work your ac compressor. over work your compressor and your compressor will go dead. which will send metal shards into your ac system, which leads to a full ac system replacement. full ac replacement = $4,000+ at the dealer.

 

CORRECTION: not the heater core. THE AC CONDENSER. sorry, got the two mixed up. it's a radiator like part that sits infront of the radiator.

 

Every TSX that I've driven has done this for the duration of the time that the ac is on, including mine. I know some of us are more sensitive to this than others, but when the ac compressor turns on, it puts more of a load on the system and you get more vibrations (and a slight rpm uptick). This is much worse when the car is cold. However, when the compressor shuts off, the vibrations settle down again until it cycles on once more. I'm not sure if this is something you can fix unless it's a motor mount issue that makes the vibrations unusually strong. Your issue MAY be different since you say the vibrations decrease before the ac shuts off. Keep in mind that if you search around the forum, many people have pointed out that our cars vibrate often more than cheaper V4's out there. Not sure why exactly. Honda has a reputation for this from what I understand. My wife's PT cruiser has less idle vibrations than my 06 tsx.