4.6 3v noise

[duststang]

4.6 3v, I noticed a noise only around 1,000RPMs in gear. It kind of sounds like a knock not a rattle. I was looking under the hood while my wife holding it steady took a broom stick all around bottom of block, oil pan, valley under intack nothing. I get close to injectors and hear it but hard to tell if injectors, maybe motion plates or around the plugs? I dont think it is a timing issue I listen to the cover and nothing. In gear if you rev higher or idle or in neutral its not as loud only there if listening under hood. Another weird thing it seems to only do it after warms up and car seems to run fine. Anyone ever eperienced anything like this? Any help is appreciated.

[duststang]

interent saying VCT phasers will knock warm at idle. Anyone know if I buy cams and phaser how much a install would cost and where is the best place? I have wanted to do cams for a while might be the right time?

[plated]

interent saying VCT phasers will knock warm at idle. Anyone know if I buy cams and phaser how much a install would cost and where is the best place? I have wanted to do cams for a while might be the right time?

pm brandon alsept he's a 3v wiz,and will steer you in the right direction

[duststang]

will do thanks

[redfirepearlgt]

HAd this occur with my05. Sound on mine would stay away until after the car went closed loop and you rev'd it a few times. Returning to idle sounded like rod knock. ITS a VCT cam phaser, phaser bolt, or VCT proportional valve that controls VCT timing would be my guess if it sounds like what you are describing. Did you have cams installed recently by chance? If yes, did they reuse the phaser bolts? Two commom mistakes in this process are reusing the phaser bolts (one time use only) and/or not finishing the torque process after setting the initial torque spec which I believe was 27ftlb. After setting that the book says to then apply another 90 degrees of CW torque on the bolt and you're done. Some forget/miss this 90 degree part.

This can also occur by using to heavy an oil viscosity such as 10W30 series vice 5W20 series. Also there is a screen under the prop valve that is a fine mesh. It can become clogged and cause this sympton as well.

Mine failed shortly after having cams installed. One of the phasers crapped out. I repalce them both and again with new phaser bolts.

http://www.youtube.com/watch?v=JmzEt2TTq7Y

This is a 5.4 with the same issue. The guy will eventually get out and let you hear the sound as it come from the engine compartment. This is the same sound I had. On mine if I shut the car off and restarted it, the moise would go away until it was rev'd again after going closed loop. Do not drie it this way. The noise you are hearing is the valve contacting the piston top due to the failed VCT cam phaser as I understand it. I had mine leak down tested afterward and there was no loss of compression on that nor an initial compression test when trouble shooting. Goof luck. Hope its this and not a rod.

[redfirepearlgt]

interent saying VCT phasers will knock warm at idle. Anyone know if I buy cams and phaser how much a install would cost and where is the best place? I have wanted to do cams for a while might be the right time?

Cams $600-800. Install cost varies. You will need phaser bolts at minimum. Additional phase limiters may be needed with more aggressive cams as well as heavier springs.

I had the detroit rocker cams made by Comp cams special grind exckusive for Brenspeed. They sounded wicked especially with LT's. Got a lot of compliments. They are spin on the thumper series put out by comp cams and are an NSR version and make great improvement on power as well. NO phase limiters required either.

http://www.brenspeed.com/detroit3vna.html
http://www.brenspeed.com/3r2z6a257da.html

[duststang]

yes this sounds similar to mine. I figured if going to have them replaced why not have cams installed. I hear it is best to have cams installed because it is a pain in the A....

[Brandon Alsept]

I have changed a lot and I mean a lot of the camshaft actuators on 4.6 and 5.4 3Vs. I would like to hear it in person to be sure, I have also saw some 3Vs wipe out the cam followers and make some weird noises here and there. I would say put cams and actuators in at min and check all the followers while its apart. Call me if you have any other questions.

513.348.8394

[duststang]

thanks,
I totally missed your number on the bottom.

[05yellowgt]

Yep, without hearing it I would look at the VCT system as your general culprit. You have to do most of the work required to change cams anyway, so if you have the extra cash I would say go for it.