Noise on start up PLEASE HELP!!

[4RunnERD]

When starting my 06 V8 Sport 4x4 when the vehilce is cold (overnight or sitting a long time) I a get clicking/slapping sound here are the details.

1. Only after a cold start up. Temp where I live has been in the mid 30's -40's
2. Seems to only do it in gear F or R at low speeds or even when stopped in gear but with foot on the brake, like backing out of the driveway. As soon I put it in park or nuetral Idle climbs and noise goes away.
3. Can't hear it when driving more than 5 mph or higher.
4. Seems to go away once the engine is warm.
5. Doesn't seem to be influecned by steering, will still make noise sitting still in gear with foot on barke and no steering input.
6. Noise stays at a constant pace, doesn't speed up slow down.
7.Best place to hear it is inside the vehicle with windows up, with windows down its hard to hear over engine/fan noise, can't park and go out to listen for it oustide because noise will go away in park/nuetral.
8. Just hit 40,000 miles, only owned for about a month if this matters.

I have read about piston slap noise on the 4.7, but if thats what it was wouldn't it make noise in park and nuetral too? Also, wouldn't piston slap noise speed up with the engine rpm? Any help would be greatly appreciated as I don't want to pay the dealership just to say they didn't hear it and have to make multpile trips. Thanks.

 

[V8 Brah]

When starting my 06 V8 Sport 4x4 when the vehilce is cold (overnight or sitting a long time) I a get clicking/slapping sound here are the details.

1. Only after a cold start up. Temp where I live has been in the mid 30's -40's
2. Seems to only do it in gear F or R at low speeds or even when stopped in gear but with foot on the brake, like backing out of the driveway. As soon I put it in park or nuetral Idle climbs and noise goes away.
3. Can't hear it when driving more than 5 mph or higher.
4. Seems to go away once the engine is warm.
5. Doesn't seem to be influecned by steering, will still make noise sitting still in gear with foot on barke and no steering input.
6. Noise stays at a constant pace, doesn't speed up slow down.
7.Best place to hear it is inside the vehicle with windows up, with windows down its hard to hear over engine/fan noise, can't park and go out to listen for it oustide because noise will go away in park/nuetral.
8. Just hit 40,000 miles, only owned for about a month if this matters.

I have read about piston slap noise on the 4.7, but if thats what it was wouldn't it make noise in park and nuetral too? Also, wouldn't piston slap noise speed up with the engine rpm? Any help would be greatly appreciated as I don't want to pay the dealership just to say they didn't hear it and have to make multpile trips. Thanks.

The RPM's are different in park and neutral. Mine does it for about 20seconds on some cold mornings. Not all. Its normal.

 

[4RunnERD]

I wonder if switching to an oil with a lower vescosity at start up would help at all. Even if I can't get rid of it completely, maybe a thinner oil will help it stop sooner, mine seems to do it every morning below 40.

 

[V8 Brah]

I wonder if switching to an oil with a lower vescosity at start up would help at all. Even if I can't get rid of it completely, maybe a thinner oil will help it stop sooner, mine seems to do it every morning below 40.

It really is no harm and it really is hit or miss. I'd stick with 5w30 as recommended.

I switched to M1 synthetic at 50k and still get it some mornings. Dont worry about it.

 

[Texas05SE]

Not that it helps you (or me) understand it any better, but my '05 V8 does the exact same thing you describe. I bought mine used and was disconcerted about it at first, but am now coming to the conclusion it's okay. Still sounds like something is awry, but like you said once it's warm it's all good. Since it happens only when F or R is engaged it leads me to think it's a noise in the tranny and not the motor unless the load of being in gear makes the engine click like that. I'm just not sure, but know you're not the only one and my '05 only has 39k on it.

 

[DaveS]

Mine does it too - has since around 40k and I am around 90k now. Only cold starts around the temps you describe and below. It's "normal"

 

[adamf]

My 05 V8 does this too. I've pinpointed the noise to be in the fuel system; you can feel the noise if you hold the fuel lines under the hood. I haven't attempted to repair yet but I suspect some combination of fuel pump/pulsation dampener/pressure regulator will be the fix.

 

[AKABlig]

I have the same: link to earlier post.

http://www.toyota-4runner.org/4th-gen-t4rs/78282-strange-transmission-knock-any-ideas.html

 

[4RunnERD]

My 05 V8 does this too. I've pinpointed the noise to be in the fuel system; you can feel the noise if you hold the fuel lines under the hood. I haven't attempted to repair yet but I suspect some combination of fuel pump/pulsation dampener/pressure regulator will be the fix.

If you come up with a fix, please post so the rest of us can try it.

I spent most of last night searching old posts and the majority of people seem to believe it is this piston slap. If that is indeed what it is, it sounds like Toyota is aware and are not planning on doing anything about. Guess I'll just have to live with it, but it did make me nervous until I heard so many other people had a smiliar issue. The other possibilties I came across were the torque converter or a cracked manifold, but piston slap seems to be what the majority of people are going with.

Update: When I purchased the car it was a 50+ degree day, didn't notice it then. Have had colder weather since, mainly 30s and low 40s which is when I first noticed it. Today it was 47 when I strated it and no noise. Looking forward to a quite spring and summer, but will be bummed when the noise comes back next fall and winter.

 

[adamf]

If you come up with a fix, please post so the rest of us can try it.

I spent most of last night searching old posts and the majority of people seem to believe it is this piston slap. If that is indeed what it is, it sounds like Toyota is aware and are not planning on doing anything about. Guess I'll just have to live with it, but it did make me nervous until I heard so many other people had a smiliar issue. The other possibilties I came across were the torque converter or a cracked manifold, but piston slap seems to be what the majority of people are going with.

Update: When I purchased the car it was a 50+ degree day, didn't notice it then. Have had colder weather since, mainly 30s and low 40s which is when I first noticed it. Today it was 47 when I strated it and no noise. Looking forward to a quite spring and summer, but will be bummed when the noise comes back next fall and winter.

Piston slap is considered normal by Toyota. The condition on my 4Runner is not piston slap. Piston slap can best be described as sounding like a diesel engine and changes frequency with engine RPM.

Cracked exhaust manifolds tend to get worse when hot, opposite of our condition. They also tend to manifest more under high load situations.

This is more of a sharp knock sound that I'm experiencing and it does not really change frequency with RPM.

 

[4RunnERD]

Piston slap is considered normal by Toyota. The condition on my 4Runner is not piston slap. Piston slap can best be described as sounding like a diesel engine and changes frequency with engine RPM.

Cracked exhaust manifolds tend to get worse when hot, opposite of our condition. They also tend to manifest more under high load situations.

This is more of a sharp knock sound that I'm experiencing and it does not really change frequency with RPM.

Will if it isn't piston slap than I am really looking forward to you or someone else finding a solution. It is rear that I have someone around when I start the vehicle cold that can put it gear for me and hold their foot on the brakes so I can poke my head around outside and try to isloate the noise. Like I said keep us posted.

 

[meltdowner]

I have the same problem, only started happening recently after I got some work done on the truck.
Spark plugs replaced
Transmission fluid flushed
Differential fluid changed

Took it home, drove great no problems. Then next morning the temps dropped around 36F and when I started it, then put in reverse I heard what OP heard. EXACT SAME SCENARIO. If i put in park noise stops. Engine warms up and it stops.

I wonder id its my ac compressor because i did have an ac leak which I havent fixed yet (its about to be winter).

Did anyone ever figure this out?

 

[FrothyLlama]

Could it be lifter noise? My V8 gets pretty loud.

Sent from my Pixel 3a using Tapatalk

 

[Anonink]

Screwdriver trick

Have u tried the screwdriver trick? Touch a long screw driver to different parts while ‘listening’. Ull b able to pinpoint location

 

[importman]

Guys, I'd be willing to bet you've got leaking exhaust manifolds. If it does it when it's cold outside and the engine is cold but goes away as the engine temp comes up it's probably it. What happens is as the exhaust heats up it expands and fills the gap between the manifold and the head. It's fairly common on the V8's.