Do fuel injectors click? Coolant Q too.

[NoSuchSol]

I'm sure this is a dumb question - Do the fuel injectors make a ticking noise on the Mazda, especially when cold? Our Lexus IS350 had a clicking/tapping noise that the dealership said were the injectors. I've always assumed that this is the case with the CX-7. If I'm looking at the engine bay, the noise appears to originate from the right side of the engine; less so from the left(belt side).

Also, I noticed my rad fan was staying on longer lately. I opened up the hood and the cap for the radiator reservoir was off! The tube was still in though. The last time the hood was open was for the dealership and I've been too complacent to check. So shame on me. Anyways, I checked the coolant level and it looked fine(this was Friday). Today, we were heading out and I had a spike on the temperature gauge. Turned around and took the other vehicle. The reservoir had ZERO coolant in it. I'm wondering if the coolant could have forced it's way out through the top of the reservoir while the cap was loose? Any thoughts? I've since topped off, ran for a little while with one quick spike, but no change in coolant levels or wet areas that I can see. I did notice that the oil filter appears to be leaking ever so slightly.

Thanks

 

[erhayes]

Yes they click and sometimes they seem quite loud. This is especially true with the high pressure direct injection engines, like my Mazda CX7

 

[NoSuchSol]

Yes they click and sometimes they seem quite loud. This is especially true with the high pressure direct injection engines, like my Mazda CX7

Thanks - I'm a little paranoid since something started acting up in the cooling system(be it leak in radiator or leaky cap). It's made the clicking noise since I've had the car, but want to make sure I'm not just telling myself something that isn't true.

 

[BRIAN_MP5T]

Direct Injection fires fuel in pulses. They most definitely do click.

 

[CX-SV]

Yes, my direct injection (plus port injection) Lexus is even louder.

 

[NoSuchSol]

Yes, my direct injection (plus port injection) Lexus is even louder.

Which Lexus do you have? The Lexus seemed a bit quieter inside the cabin than the CX-7 does compared to clicking.

 

[CX-SV]

Which Lexus do you have? The Lexus seemed a bit quieter inside the cabin than the CX-7 does compared to clicking.

IS350, it's louder outside of car only. Inside about the same, (IS and CX-5) neither car intrusive (regarding clicking sound).