rattling noise when cold

Hi, I just bought an 05 tacoma, I had a 93 previously. Now that the weather is getting cold, there is a rattling noise coming from the engine compartment. When I press the gas, the noise intensify but goes away when the engine warms up. It's not a valve noise but i can't seem to find anything loose, did it happened to anyone else? And what could it be?
Thanks

 

My 2000 made a tapping or ticking noise when below 40f and it went away when warmed up. My 08 does the same. Most posts on TW seem to say it is piston slap. I put an oil pan heater on this summer to see it it makes a difference but it hasn't been really cold here yet. I'll see what happens but even if it doesn't stop the noise it should make the warm up quicker. Everyone on TW says it won't cause any harm. Assuming it's the same noise hope this helps. If it's not the same noise don't read this.

 

Check where the cold air intake joins the right fender. This has some foam around it, but it rattled when cold on mine until I learned of the TSB. Simple fix it to stuff some added foam around the plastic/metal union. Problem solved. This MAY be your cold rattle.

 

mine does this too!


starts as a rattle at like 15 km/hr and at 30km/hr it sounds like a vibration. any speeds above that and it disappears. only does it first thing in the morning too on a cold day.

 

I had the exact same sympoms. I read on TW there was a TSB on this. I just padded the CAI where it entered the right fender well and the rattle dissappeared!! Try it!!

 

i'm going to try that this morning! thanks for the tip

 

Hope it works. That is what TW is all about. Spread the word, spread the tips (sounds like a BBQ).

 

X2
I plan to do this fix soon. On my first start reversing out of my driveway I have the rattle.

 

YUP!!! My biggest rattling was reversing out of the driveway in the morning. It did not happen much when it was warmer during the summer, but when it started to get cool in the mornings, I noticed the rattle.

I am pretty sure your fix is in adding some foam padding to the CAI hole in the fender. Should take you about two minutes.

 

Cool. I've heard this on mine as well.

 

how about when you turn off the truck and it makes the knocking for like a min,, is that good or bad? I put in octane 87. I usually use BP or Shell gas!! Also, last winter in the cold, the engine's pulley would make this weird noise but once it warms back up, the noise is gone! what do u guys think?

 

It's bad to let it go on. I would put up a seperate post about it so the engine tech types can help you diagnose it. I think the problem is called "Post-Ignition". I believe it's a timing issue. Title your post something like "Engine Problems: Post Ignition." You should get some knowledgeable replies.

 

I have a 2007 that did it since new. I took it in at 35,900 miles to get covered under warranty, and the service tech said it was the intake on the fender. He was surprised that mine wasn't fixed with the new part. They installed a whole new plastic intake on the fender and I haven't heard a noise since!

 

Thank you all for the speedy response. I'll check out the air intake first thing in the morning. Bing

 

Old thread- but glad to see this thread. My truck did this for the first time this morning. It was frosty out- and when I started the truck it sounded like the valves tapping pretty loud. I was like WTF! I bought this thing new and it has never done this in 70,000 miles. It went away as soon as it warmed up- but did not sound good at all. Its got plenty of good oil in it. Advise?

 

my truck does the same thing its an 08 with 40k.... loud valve sounding noise im going to take it to the shop soon.... does anybody else have this problem?

 

Your sound is normal if it sounds like valve ticking. The others above are referring to the plastic intake pipe that goes through the fender. There is a thread about that ticking somewhere but it's normal.

 

I have no experience with 4.0's. I have a 2.7. I did a oil pan heater that I used this winter under 32F. I just switched to syn. No more tick this winter on dino with the heater. No tick on syn w/o heater this spring so far. Wonder if I'll need the heater next winter with syn.

 

When it is very cold, 25f and under, I get an intermittant whine from my power steering pump as it warms up. I know it is coming from this, as it will change in pitch if I turn the wheel. When it warms up it goes away. I first thought it was a bearing that shot craps, but after the temp came up above freezine (two day later) it stopped doing it. Now every time it is cold I can count on hearing it. I guess it is normal.

 

Could be a cracked heat shield as that would explain why the sound goes away when the cat. converter warms up.