[Miserywizard]

So, I noticed today that when I turn the blower on, the engine RPMs take a dip, come back up to normal, but the engine starts vibrating a lot more than normal.

It seems a little excessive, but not sure if I need to get this looked at or not.

Driving around without the blower on seems to be a little smoother and less taxing. RPM going from driving to idle when coming to a stop seems a bit more stable, as well. Is the blower on its way out, or is this just normal behavior?

 

[alpinegreenneon]

Must be quite a big amp draw. Check for codes? Were the spark plugs ever replaced? Original engine mounts?

 

[Miserywizard]

I don't have a way to check the codes, unless I take it in. I got the car used at 70k miles, no mention of spark plugs, or mounts being replaced in the papers I got with it. I've been meaning to get the plugs replaced, and I'll ask the shop to check the mounts while they're at it.

 

[RNSX]

I also have noticed the same thing with my dart. I have close to brand new plugs and coil packs and it really didn't change anything. Never had a code or anything thrown by it. Once it's up to driving speed or warmed up though it's really a non issue on mine. Just runs like it's being taxed more at idle. It's actually slightly worse on internal air recirculation too even when fully warmed up. It is worse if i come to a stoplight or stop sign when the motor is still warning up very soon after starting it and it's colder than 32 degrees. In that case, it will act like it's going to stall but never actually does and still throws no codes. It's fine once you hit the gas again.

I have read before that some people attribute it to the engine coolant at some point when it's nearing the end of it's life. Mines coming up on 10 years 140kmi and I'm getting it changed out and a slightly leaky radiator hose fixed up when my inspection comes up in August. I'm actually wondering if it may actually do something or if it won't change at all.

 

[Miserywizard]

I also have noticed the same thing with my dart. I have close to brand new plugs and coil packs and it really didn't change anything. Never had a code or anything thrown by it. Once it's up to driving speed or warmed up though it's really a non issue on mine. Just runs like it's being taxed more at idle. It's actually slightly worse on internal air recirculation too even when fully warmed up. It is worse if i come to a stoplight or stop sign when the motor is still warning up very soon after starting it and it's colder than 32 degrees. In that case, it will act like it's going to stall but never actually does and still throws no codes. It's fine once you hit the gas again.

I have read before that some people attribute it to the engine coolant at some point when it's nearing the end of it's life. Mines coming up on 10 years 140kmi and I'm getting it changed out and a slightly leaky radiator hose fixed up when my inspection comes up in August. I'm actually wondering if it may actually do something or if it won't change at all.

All that makes a lot of sense. I'm definitely hyper focused on everything that is going on with the car, cuz it's my first time owning a car and I'm not sure how everything should be behaving, or what is "normal". Could very well be that this just how it operates and everything is okay.

I had a coolant leak a couple months back and had it fixed and new coolant put in. I've also just had the oil and transmission oil replaced. It runs perfectly fine at the moment. But sometimes I'll like, be idling and hit the window button and see the needle bob, same with turning the air on and noticing the engine pitch change, and I get a little nervous.

Is there a word for being a hypochondriac about your car?

 

[xXNickisXx]

I got my '16 1.4 used at 24k MI in about August '21. I can say mines done that since the day I got it. It's a little more funky with the manual though because you have to remember loading the engine from a stop is about 30% more load seemingly with ac on and it tends to stall easier. Haven't replaced the coolant yet but have plugs and coils with effects yet to determine. It's only the ac that bogs it to stall though.

 

[GiantRobo]

Don't forget the AC will switch itself on whenever the computer thinks you need it. Whether you want it or not. That's what lugs down the engine. The blower is just a 12v squirrel cage fan. I've felt my car kick the AC on if it thinks it's too humid in the car, for example. It doesn't light up the AC button, and you can't manual turn it off. I love hand-holding tech!

(Like have you ever noticed you sometimes can't turn on recirculated air? The computer decides whether or not you get to choose outside air. )

 

[xXNickisXx]

One thing I can say that corresponds to OP is that when environmental conditions wouldn't warrant the automatic AC operation, just turning the fan on at high (anything over 4) tends to introduce much larger than expected vibrations throughout the vehicle. IDK if its due to the fan itself or engine load.

 

[alpinegreenneon]

The blower motor fuse is the PDC is a 40 amp and the AC clutch is a 10 amp. If you select defrost, that automatically turns on AC. So there can be a large amp draw that will effect rpms momentarily.