Loud clicking noise.

[Fred D.]

Hi, I own a 1994 Q45 with a 120,000 mileage. I drive it every day, and is well maintaned. Today I heard a loud clicking from under the hood , so I popped open the hood to locate noise, it was coming from the passenger side of the engine(upper & middle part). I could not see what was making this clicking noise. Every twenty seconds or so it would click and after the click the engine would sound diffrent but the rpms stayed the same. Please help!

[Ozzie]

Not that I have an intimate knowledge of your model, so this is a fairly generic answer...

Sounds like a solenoid or switch activating....Maybe for thermo fans, or A/C, or a flow control valve of sorts.....

Anyone care to elaborate further ?

[Fred D.]

Ok, thats a good start, the A/C or a function that is suppose to happen. I have never heard this clicking befor, I just want to make shure it is not a problem waiting to get worse. My fuel pump is starting to hum, if that could be related. I plan on replacing my fuel pump as soon as I find a OEM for less than 300$.

[PopPop]

Sounds like it could be a faulty fuel injector! Ohm injectors to see if there's a guilty party!

[Jeff Williams]

My fuel pump is starting to hum, if that could be related. I plan on replacing my fuel pump as soon as I find a OEM for less than 300$.

I wouldn't wait too long. The FPCU costs more than the pump does. Be sure to buy your parts from http://www.everythinginfiniti.com Call the number and talk to Joe. He might still be running the free shipping deal.

If you are a meticulous mechanic, you might be able to take the pump apart, and clean it. It seems feasible, but I haven't heard of anybody reusing the old pump.

Leave your A/C and defrost off, and see if the clicking continues. It could be the compressor engaging. There are low pressure switches that disable the compressor if the R-123 level drops.

[maxnix]

1.) I wouldn't wait too long. The FPCU costs more than the pump does. Be sure to buy your parts from http://www.everythinginfiniti.com Call the number and talk to Joe. He might still be running the free shipping deal.

2.) If you are a meticulous mechanic, you might be able to take the pump apart, and clean it. It seems feasible, but I haven't heard of anybody reusing the old pump.

3.) Leave your A/C and defrost off, and see if the clicking continues. It could be the compressor engaging. There are low pressure switches that disable the compressor if the R-123 level drops.

1.) Until the end of the month. About $235 last I looked. Get the O ring and a filter.

2.) Look for posts by Texasoil and his pictures in Member's Rides.

3.) Check the R134a using dedicated guages, or go to an AC specialist. If you really want to be proactive, get a dryer form Joe and flush the AC before it fails.

[Fred D.]

I checked the ohm resistance on each injector pin read ok ranges 10-15. I have looked at posts of nico members on fuel pump replacment, I will do it very soon because of the computer controlled device may fail if I wait to long. It is a lot of fun to keep my car running at its peak no matter the cost and labor, because I expect peak performance!