Tacoma making strange noise after putting back valve cover?

Hi I'm new here, and have done the dumbest thing to my Tacoma. It's been making this slight ticking noise at idle that you have to listen closely to hear. I ended up taking the top of the engine apart to get to the left valve cover of the 5vzfe to take it off. I'm no pro at mechanics at all, but I checked if the spark plugs were loose... They were not, and i don't see any wear. I put the Valve cover back on and the intake housing on top of the engine back with all the nuts, bolts and hoses in the correct places... I reconnected the battery and started it up only to get a strange noise that sounds like a metal to metal whistle kind of noise and slows the engine RPM at idle. What could I have possible done? I'm positive I didn't drop anything in the intake manifold.

 

Hmmmmmm, interesting. Not missing any parts or tools?

Used a new gasket? Maybe crankcase pressure causing a whistle? Im just guessing here without more info.

 

Everything reconnected properly? Including PCV valve hose?
Does it still idle and run properly?

 

Did you replace your gaskets and torque everything correctly? A "whistling" sound may be a vacuum leak, so check all your tubing lines.

My 3.4 has always had a mild ticking sound to it, not sure if it is normal, but it has done it as long as I can remember.

 

Well I know of a Toyota mechanic so he's coming to take a look. I did not really torque things properly at all. I just tried not to tighten too much, but that was just dumb. I should have gotten a torque wrench since I'm new to taking apart what I did. Anyways, thanks for replying, and hopefully I get it running properly again.

 

Good luck. Let us know what you find... in case any of us have the same issue.

 

Well, i fixed it. It was just 1 little tube I forgot to put on that was hiding underneath the top intake housing! It's in great shape for 16 years old, and I just detailed it after it was smothered in mud and dust. I got a pic of it.

 

Fwiw most mechanics don't torque valve covers lol

 

Well the truck still has that tick noise. It could be oil filter related. I got a Bosch Premium oil filter for it when I did an oil change for it, and that's when it started to make a tick only at idle when the engine is at operating temp. The last oil I used was a Pennzoil conventional and thought using conventional was causing the tick at first. I used to always use synthetic. I switched to Royal Purple HMX oil. It still ticks, but takes longer for the tick to come back again when driving. I guess the Improved flow of synthetic helped a bit. Now, I'm after the Bosch oil filter because it may not give good flow. I bought a Denso First Time fit oil filter on Amazon that should be arriving in a few days. The Denso filter is bigger, and I read it has great flow. The Bosch oil filter still had plenty of life after quickly changing from conventional to synthetic, but I'm gonna switch it out. Luckily I have some leftover Royal Purple HMX oil to fill it back after I spill oil from replacing the oil filter.

Also, when I put the top of the engine back together after putting the royal purple oil, the engine felt more peppy. I have no idea if it was the oil that made it better, or putting things back nice and tight. It accelerates noticeably faster when I give it less gas to rev with. When I accelerate normally, I also noticed the transmission making a mild "bump" when it shifts now. It used to only do that "bump" when I drive fast, so I guess it's making more power/torque at lower RPM. Well, Royal Purple is now my favorite, and I don't remember other synthetics doing that. It's expensive though, but can probably be pushed between 7500 to maybe even 10,000 miles until the next change. Automakers are telling their customers to come back for an oil change every 10,000 miles due to the quality modern synthetic oils. Even our Jeep dealer, for our 2013 Grand Cherokee HEMI, said every 10,000 miles.

 

slight ticking noise is normal on these motor.

 

Yeah like a lot of other engines too, but it's weird hearing a louder one from one lifter ticking, and sometimes even not ticking until several seconds into idle. Not to mention it never did that before using the filter. Might as well give a new oil filter a try since it could be a cheap solution. If it doesn't work, oh well I'll just ignore it. If the tick does stop, then I'll make a new thread about it and the Bosch oil filter not being a good filter for the 5vz