dj maskell

I'm having an intermittent and inconsistent problem with the A/C in my 2006 RL, and I'm not sure if the info I have gleaned so far is enough for a competent Acura mechanic to figure it out even if he can't necessarily reproduce the issue on his own. (or if not, I'm looking for any advice on things I should do when the problem crops up again so that I can provide a mechanic with useful information about the problem) Any advice would be greatly appreciated.

Here's what I'm dealing with:

• The A/C will occasionally blow uncooled air for a minute or two. This seems to occur most often when stopping/stopped at a red light. The cold air always comes back: sometimes while still idling there at the light, other times it doesn't return until moving again. The problem does not seem happen while cruising on the highway.
• Some days it seems like it's cutting out at every stoplight, other days it runs without a single problem.
• I think it might be occurring more often when the temps are over 90F, but I don't have enough data yet to confirm that hunch.
• Compressor is not original, it was replaced 3 years ago.

One fortuitous night, the problem conveniently started up after I pulled into the driveway, so I did some experimenting:

• The air temp was about 90 or higher and humid. The compressor and fans were working and the air coming from the vent was nice and cold, but then it got warm. So I popped the hood and observed.
• I noticed that the engine would suddenly idle down slightly as though an additional load were added to it which was immediately followed by the compressor and fans cutting out. The engine quickly returned to normal idle and shortly thereafter the compressor and fans re-engaged only to cut out again in the same way in a repeating 10-second cycle.
• I slapped on a meter from one of those DIY recharge cans on to the low pressure port to see what I could see.
  • While operating normally, pressure was about 45psi @ 90+ outside air temp
  • When it kicked out, the pressure jumped to about 100psi
  • When it kicked back in, the pressure dropped to slightly above 55psi before cutting out again
  • After a few cycles, it stayed on and the pressure slowly dropped from 55 down to about 50 over the course of 30 seconds or so and stayed on and working.
  • When I idled up to about 2000rpm, the pressure would drop to about 42 psi, but after 5-10 seconds at this idle, the cycle would begin again.
  • If I just left it alone for a minute or two, the cycle would usually stop on it's own.

Since I can't reproduce this issue consistently, any thoughts on what I can do to provide a professional with useful info the next time it happens?

dj maskell

(Also, thank you to all the wonderful contributors on this forum. I've been lurking unregistered since at least 08 because any time I've had a problem with the Acuras I've had over the years, 93 Legend, 01 TL, 06 RL, or 10 MDX, I'd find that someone else had already asked about it and got a solid answer too. It's been immensely helpful.)

TakeiTeg

A/C relay, very cheap and easy to replace so try replacing the relay first, sounds like the relay is about to go.

dj maskell

I'll give it a shot. Will try to loop back and indicate if this fixed the problem or not. It may be hard to tell for sure, as I haven't been able to replicate the problem since I posted about it.