The Loud Buzzing Under The Hood (TCS Actuator)

[CINNALOCKS]

Okay so on the 94Q (which is looking pretty sweet after her cosmetic surgery) I replaced the ABS Relay a few months ago and the sounds went away. About a month ago or perhaps longer, I began hearing this other noise under the hood (Same family of sounds only louder) I could not pin it down until today. The TCS and Slip lights had been on and off, mostly on over the past month as well.

I met with Wes today and he did a test on the TCS, it came back a code 18. As I recall that means the fluid pressure is low in the motor... And that more than likely, the issue is the TCS Actuator, rather than the TCS Motor. I have been informed that those are expensive new parts that do not usually fail,

I am just looking for some feed back from anyone else who may have had a similar problem, parts for sale or direction. I am pushing 178k.

[elwesso]

To add what he said, the buzzing is coming from around the passenger side wheel well, where the TCS pump is.

Code 18 from the FSM is "operating oil pressure low" or something like that..

Heres a thread from "yesteryear" that I was able to dig up.. Look for more posts from rsiwicki, i know he had more posts about the TCS actuator problem.

zerothread?id=134681

[CINNALOCKS]

Well I found the actuator and some other parts from Mike in Cali. Amazingly we have had very cold weather and each day when I atarted the car, the buzzing goes on and then the lights come on, recently to include the brake light. I read other post on this matter and understand, that the brake light comes on when there is low fluid. I continue to check, but the level is good.

Well we have had a slight warming trend up to fourty degrees and the tcs and slip light have not come on for the last two days and no more noise. To make it even stranger I have a bad number three fuel injector, which has been making the cel go off, but, as the weather has warmed it too has gone back to normal.

I certainly plan to replace them all, but thought it was odd after at least thirty days of buzzing and light,all day, every day, now no lights or buzzing. I continue to miss Cali and always knew that warm weather, not zero, is my friend. Thanks to Wes and Goody for your personal assistance in this matter.

[in94q45]

My 94 q45 has a code 18 also(low operating oil pressure). The FSM recommends to check the TCS actuator as well as the TCS pump. These ARE expensive parts to replace. I do not hear any buzzing. Should the buzzing be obvious? When it is code 18, what other problems could there be other than replacing the parts? A new TCS actuator is over $2000 and a TCS pump is over $1000.

Can anyone give me some feedback. Could it be as simple as a bleeder retorque? Relays? I replaced the 2 blue relays under the battery to no avail. Other electrical problems or connections that need reparing? Could it just need a TCS fluid replacement?

If anyone has had this same experience with having a code 18 or knows what the problems could be, that would be great!

I am taking the car to a mechanic this weekend and I want as much info as possible for him.

Also, does anyone know where I can get a USED or aftermarket TCS actuator or TCS pump which will fit my 1994 q45, if indeed that is the problem?

[Infinitiguy19]

The Service Manual says that you should tighten the TCS Actuator bleeder to 8.8- 11.7 Foot Pounds of Torque. Basically make sure the TCS Actuator bleeder is a little more than finger tight. I was going to refer you to Wikipedia but that can sometimes be inaccurate. Once you have tightened the bleeder check the TCS codes again.

Have you checked all your fuses?

And the part number for the TCS Actuator is 41810-60U00. Any 1991-1996 Infiniti Q45 TCS Actuator will fit your vehicle. Try Car-Part.com to find one and make sure you go to a place where its not already off the vehicle and the gauge cluster is still on the vehicle. If you a perfectionist like me ask to see if the millage on the vehicle has been altered at all (Taking the VIN to a dealer, Asking nicely...)

[Mint Q45A]

This may help...although it may not be the most technical approach, though...

Considering that the pump gets energized for about 5 sec every time you start the car, and (I believe) it recyculates some of the fluid in the system, you can use it to exchange the old fluid. At the same time you can purge out any air trapped...

This is what you can do:
- Using a turkey baster, remove the old fluid from the reservoir/tank and replace it with clean (DOT 3). You may want to fill it up past the Max line.
- Start the car and let it run for a 10 or 15 secs
- Loosen the bleeder underneath the reservoir. Note: The system bleeds into the reservoir, via the return line. You may see airbubbles....You will also see some dirty fluid mixing up with the fresh one in the reservoir
- Replace all the fluid in the reservoir, again, using the turkey baster
- Tighten the bleeder (go easy on it...you dont want to mess it up)
- Restart the car, let it run for a 10 or more secs. Note: You will notice that the fluid level in the reservoir drops a bit
- Bleded, replace the fluid and repeat several more times...maybe 8 or 10.... Until the fluid in the reservoir is clean...

Note: Another option is to disconnect the lines going to/from the pump, drain the fluid, replace it, purge, etc...

My two cents....