so i noticed that when i'm sitting at a light and the compressor for the a/c kicks on, the car shakes a little like it's about to shut off. also i have noticed that when you are moving, the a/c is cool, but when you are sitting a light, it gets warm until you start moving again. are these common issues with the 5?
a/c and vehicle reaction????
- Thread starter 2003proes
- Start date
It sounds pretty normal.
Are you running the A/C on Recirc or Outside Air?
- Outside air will definitely warm up at a light at you are drawing in engine heat radiated through the hood.
- Recirc should help keep cooled at a stop. I tend to use recirc in traffic, or at a light in my vehicles.
The idle drop is also pretty normal. One of the downsides of 4cyl cars is that accessories like A/C and power steering tend to be a real draw, at idle. Every 4-cyl cars I have had idles rough with A/C on at idle.
If you really want to see the draw, accelerate moderately and turn off the A/C mid-acceleration. It should give you shades of the old Knight Rider "turbo boost" button. The 5 isn't nearly as bad as my Toyota Echo as it's only a 1.5L 4-cyl. I have learned to use this "turbo" function while accelerating and to turn the A/C back on once up to speed.
Are you running the A/C on Recirc or Outside Air?
- Outside air will definitely warm up at a light at you are drawing in engine heat radiated through the hood.
- Recirc should help keep cooled at a stop. I tend to use recirc in traffic, or at a light in my vehicles.
The idle drop is also pretty normal. One of the downsides of 4cyl cars is that accessories like A/C and power steering tend to be a real draw, at idle. Every 4-cyl cars I have had idles rough with A/C on at idle.
If you really want to see the draw, accelerate moderately and turn off the A/C mid-acceleration. It should give you shades of the old Knight Rider "turbo boost" button. The 5 isn't nearly as bad as my Toyota Echo as it's only a 1.5L 4-cyl. I have learned to use this "turbo" function while accelerating and to turn the A/C back on once up to speed.
An interesting note, going along with the 4cyl. & A/C thing, is that it's designed to temporarily shut off the A/C system when you really wring out the RPM's near redline. This feature to ensure you're getting every ounce of power you need from the engine to be delivered to the wheels instead of cool air to your face.
Try it sometime, have the A/C on full blast arctic chill to your face... quickly approach the redline and it'll turn into balmy summer breeze
Try it sometime, have the A/C on full blast arctic chill to your face... quickly approach the redline and it'll turn into balmy summer breeze
I will certainly try the recirc vs. vent idea. i am not really sure which one it is on. thank you. and as for the shaking issue, is there a way to minimize that? like better grounding or better wiring? and as for the warm air at high rpm's, i had noticed that, especially in the crown vics at work when you get on it. don't really drive the 5 too hard...yet...
its not an electrical issue. its a mechanical one. The AC pulley puts a load on the engine, making it work harder.
rweatherford
Member
- :
- Mazda 5
Perhaps this is a manual transmission issue? Our car is always smooth AFAIK. Guess I can try to pay a bit more attention. I don't think it gets warm either, but we always run on recirc.
the AC would have nothing to do with the transmission...
this has to do with the power of the AC bogging the engine.
i dont notice it nearly as much in my moms RDX (which as a turboed 4 cyl) as i do in mine. Which is why i never run the AC in my car. makes my idle rough and my car more vibraty
this has to do with the power of the AC bogging the engine.
i dont notice it nearly as much in my moms RDX (which as a turboed 4 cyl) as i do in mine. Which is why i never run the AC in my car. makes my idle rough and my car more vibraty
rweatherford
Member
- :
- Mazda 5
I disagree that it can't have anything to do with it. I suppose your 7lb flywheel didn't make any difference?
An automatic transmission car has a load on the engine at all times at a stop light. Manual transmission does not. An automatic transmission also has a heavy torque converter bolted to the flexplate. It also has fluid inside it.
A manual transmission car has basically no load on the engine at a stop and has only a flywheel and clutch pack bolted to it. Even the motor mounts may not be in the same location on manual and automatic tranmission options. I've seen this before in other cars.
I'll try to pay more attention to the engine vibration next time I drive the car. I only drive it about once a week.
I haven't noticed the effect on the 5 (4AT) too much, but it is there. also, as a clarification on my earlier point, power steering can do the same thing in general, but the 5 does have an electric pump, so it shouldn't rob mechanical power.
If you really want to see a weird thing though, crank the steering at idle with the headlights on. The Electric Power Steering is a definite electrical draw!
If you really want to see a weird thing though, crank the steering at idle with the headlights on. The Electric Power Steering is a definite electrical draw!
yeah, i see what your saying...
