V8 Engine Problems

T

TONEDOG513

New member
Hi,

4.7L 2UZ-FE

Engine rattles during hard acceleration. Sound like pistons or lifters maybe timing chain rattle (but I think I have belt not chain in the 2UZ-FE)

This has been since the motor was factory new.

I use premium (93) mobile or shell gas

Lately I have noticed, rattling under slow acceleration up small hills while the a/c is on, and alot of rattleing when the engine is hot, a/c is on and hard accelerate.

56k on the motor

plugs changed at 30k

any ideas
thx
tony
 
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V8 Engine Issue

Hi,

I could really use some help/advice.

I have a 2007 Toyota 4runner Limited 4.7L V8 2UZ-FE

After sitting overnight, when I startup in the a.m. and put it into any gear while holding the brake i get a knocking.

The knocking is definately engine, sounds like lower engine, a lower frequency knock, not like tap or a rattle.

The severity changes depending on the teperature, worse during colder days.

I always let the the motor run for a few min, at least until the needle passes the "c" on the temp gauge before moving.

It lasts for a block or two, or about 2 stop signs, hearing it at each stop sign.

I use Mobil1 5-30, change every 3k no matter what.

I use premium gas (93) from moble or shell

What could this be?

Thanks for any responses,
TONEDOG
 
I am not sure what is going on with your engine, but it is not normal (IMHO).
I have the same V8 and it is quietest engine I have seen in any trucks…
Since you still under powertrain warranty (60K ; 5 years) I would go to dealer immediately.
 
Well, can't say for sure, but sounds like you've got a rod about to let go.

Warranty or not, get to repair shop ASAP...and drive it as little as possible.
 
jwyshrek said:
Well, can't say for sure, but sounds like you've got a rod about to let go.

Warranty or not, get to repair shop ASAP...and drive it as little as possible.
Click to expand...

I agree !

Might be worth a trip to have it diagnosed, better to fix it in the shape it is in right now compared to it "letting go" and paying for an entire short-block.

Good Luck
 
Check it out

Definitely go to a Toyota dealer immediately. I would not even go to a private shop. I have a V8 and I agree that it the smoothest, most quiet engine that you will ever find. I finally have some growl since installing a Magnaflow cat back system.

Don't let it go!
 
TONEDOG513 said:
Hi,

4.7L 2UZ-FE

Engine rattles during hard acceleration. Sound like pistons or lifters maybe timing chain rattle (but I think I have belt not chain in the 2UZ-FE)

This has been since the motor was factory new.

I use premium (93) mobile or shell gas

Lately I have noticed, rattling under slow acceleration up small hills while the a/c is on, and alot of rattleing when the engine is hot, a/c is on and hard accelerate.

56k on the motor

plugs changed at 30k

any ideas
thx
tony
Click to expand...

Is that to say it's not the original? Also, I thought the V8's were 100K mile plugs? Was it mis-firing at 30K or were some 30K mile plugs?
 
Last edited:
Well, to start off your engine has a timing belt not a timing change. The service interval for the belt is just over 80k miles. Why did you change your spark plugs at 30k? The spark plugs are rated for 122k miles. Did you use regular plugs? That could/would cause interesting things. The truck calls for iridium plugs and they are expense for 8. In Canada we can pay upwards for $14.00CAD a plug.

Just a couple of thoughts,

Netwon
 
WOW! thanks for all the replies... im impressed....

I try to answer everyones comments...

1st I'd like to preface this by telling you guys that I am the computer consultant for the dealership that I bought the truck from. So I get to hang out with the techs, as I service the computers that service our trucks while they are working on my truck. Over time I figured out who the best tech in the shop was and stuck to him like glue. I also have the owners ear as he loves asking me questions and will always look into anything for me with no appointment ect...

There is only one problem he and all the other techs say that all the stuff going on with the motor is normal. :/

I thought that if anyone, i'd be able to get someone over there to help me figure out whats going on with this motor, but in actuality I think its working against me, as its tough to be a d&*k and demand fixes.

The truck has been maintained by this dealer since mile 1, oil changes everytime I come to do computer work, with mobil 1.

newton - I thought it had a belt, but thats what it sounds like, similar to the 4.0 sohc timing tensioner issue that was so big a few years back with the ford explorers. I had the dealership change the plugs as i get them for free and figured every 30k would be a good thing. yes they were the iridum plugs.

dk27 - It is the original motor, I guess the wording can be interpreted differently.

jwyshrek - how can a mechanic test/check if a rod is gonna go?

Thanks again for all your help,
Tonedog

ps.. if anyone knows a really good motor shop in NY area, i'd be willing to pay for a diagnosis, so atleast I have something to bring to the dealer with.
 
Last edited:
TONEDOG513 said:
WOW! thanks for all the replies... im impressed....

I try to answer everyones comments...

1st I'd like to preface this by telling you guys that I am the computer consultant for the dealership that I bought the truck from. So I get to hang out with the techs, as I service the computers that service our trucks while they are working on my truck. Over time I figured out who the best tech in the shop was and stuck to him like glue. I also have the owners ear as he loves asking me questions and will always look into anything for me with no appointment ect...

There is only one problem he and all the other techs say that all the stuff going on with the motor is normal. :/

I thought that if anyone, i'd be able to get someone over there to help me figure out whats going on with this motor, but in actuality I think its working against me, as its tough to be a d&*k and demand fixes.

The truck has been maintained by this dealer since mile 1, oil changes everytime I come to do computer work, with mobil 1.

newton - I thought it had a belt, but thats what it sounds like, similar to the 4.0 sohc timing tensioner issue that was so big a few years back with the ford explorers. I had the dealership change the plugs as i get them for free and figured every 30k would be a good thing. yes they were the iridum plugs.

dk27 - It is the original motor, I guess the wording can be interpreted differently.

jwyshrek - how can a mechanic test/check if a rod is gonna go?

Thanks again for all your help,
Tonedog

ps.. if anyone knows a really good motor shop in NY area, i'd be willing to pay for a diagnosis, so atleast I have something to bring to the dealer with.
Click to expand...

Do you have any warranty left on the vehicle? With only 56K I would think you would. If you have a warranty I definitely wouldn't take it anywhere that wasn't a Toyota dealership and have an once of work done.
 
There are experience mechanics/tech out there than can tell by just the sound the engine makes...some have a knack for it.

But to make sure, the bottom end of your engine has to be opened up, rod caps removed and the bearings inspected...only real way to know for sure.

By the way, have you checked your oil level lately? Any lights on your cluster gauge lit up?

Again, there is no way of knowing just from a worded description...but from what you describe, it does not sound normal or in any way good.
 
TONEDOG513 said:
Hi,

4.7L 2UZ-FE

Engine rattles during hard acceleration. Sound like pistons or lifters maybe timing chain rattle (but I think I have belt not chain in the 2UZ-FE)

This has been since the motor was factory new.

I use premium (93) mobile or shell gas

Lately I have noticed, rattling under slow acceleration up small hills while the a/c is on, and alot of rattleing when the engine is hot, a/c is on and hard accelerate.

56k on the motor

plugs changed at 30k

any ideas
thx
tony
Click to expand...

just a question, but doesnt that engine require 87 octane? if so, why are you putting 93 octane in it? putting wrong octane could be the problem for that long
 
dk27 - yes I purchased the platinum to 100k warranty with the truck

jwyshrek - yikes that sounds like fun! There is something about factory sealed that make me hate wanting to have the lower end taken apart, but i will to solve this issue.
- no lights commin on, everything according to the electronics displays/warning systems is good.
- oil is perfect level, looks normal in color

T4F - I have always run 93 on all my trucks, Also with so much info out there on the benefits performance wise, even if only a little by running the better fuel, I figured I was good. I think it even says to run it in the glove box book, now you have me curious, im gonna go re-read that.
- god could you imagine if I put 87 in there, I prob get a ticket for noise pollution. I say that only because I figure it make it worse.

I really am gonna get this thing to the dealer. God, I don't look forward to dealing with the blah blah required to get someone to pickup a wrench, its exhausting.

but either way at least by talking with you guys I have a direction, I can say "hey open that bottom end"...

thanks for that.

Any ideas let me know.

Tonedog513
 
The knocking you hear when the engine is cold is the piston slap. It's fairly common as many people have posted about it. One post said Toyota knows about it, and it doesn't hurt the motor.

Once the motor warms up, the seals expand, and the noise goes away.

On your rattling, you'll have to explain the noise in more detail.

If you are in tight with a dealer, how come you just don't ask them to diagnose the issues?
 
midnight runner said:
The knocking you hear when the engine is cold is the piston slap. It's fairly common as many people have posted about it. One post said Toyota knows about it, and it doesn't hurt the motor.

Once the motor warms up, the seals expand, and the noise goes away.
Click to expand...
I have piston slap, but only hear it on cold starts in the winter. It goes away after 30 seconds or so.
 
Again, hard to say what it is just from a worded description...but didn't he state that it made noises when 'hot' as well as cold?

I just remembered on the Jeep 4.0L...if you have carbon build up in the cylinders, it would make a 'rapping' or knocking noise either hot or cold...piston slap.

Noises are hard to diagnose...some are benign and some are indications of serious problems.

In either case, I would have it checked out just to be safe.

One thing that could help and some folks over at the XJ forum has done this...if you can...record video of the sound and post it on youtube...so people can get a better sense of what the noise is like.
 
can you make a video or record a sound clip? i get the knocking and tapping noise but it mostly goes away after it warms up... just slightly hear the tapping noise. maybe something is loose causing the rattle noise?
 
midnight runner -

1, im hearing the embarrassing and annoying pisiton knock in the summer time in NY when its 90 degrees in the morning and it lasts for two blocks after letting it run for over 5min in the driveway. can you imagine what the sounds like in the dead of NY winter and how many blocks it lasts for? I dont think that is acceptable nor mormal, do you?
2, the rattling im guessing is detonation. problem is that im running 93 octane, it does it up hills, it does it when the tranny shifts gears (when load is reduced and re applied) and if I accelerate really hard it sounds so bad that it almost sounds like im smashing every lifter in the truck, i know detonation is the pistons, and if the sound im hearing on the heavy acceleration is infact the pistons, im going do do damage.
3. as for the being tight with the dealer, it makes it harder beacuse i cant blow up on them as it would hurt the working relationship on the other hand trying to get them to open that motor up is almost impossible. they use the computer check for codes, they ask me about my gas type, they use the "normal" excuse and the "v8 is bullet proof" excuse and send me on my way. the problem is getting them to do anything you have to be on top of them, i'll have to take a few days off from work to babysit over there. dealers suck, that why I'd rather pay a "super tech" if I could find one to make it all perfect, including finding a way to resolve those tolerance issues causing the "piston slap" on startup.

guys, it will be hard to get a clip as i have to be driving to make it happen, i guess i could tape a small recorder inside the engine bay and see if I can catch it on tape.

thnks
ton
 
What about exhaust leak, particularly cracked exhaust manifold? Would definitely explain why the noise is worst when engine is cold/under heavy load. This happened to a Nissan Armada I had (very common), and I'm pretty sure I've heard reports of cracked exhaust manifolds on v8 runners on this forum.

I had both manifolds replaced for no charge under the emissions warranty on the Armada since the manifolds and catalytic converters were one piece. It was like a $2k job. I believe the 4Runner manifolds are set up the same way.

You could also try a few tanks of regular gas, wouldn't hurt anything since the truck is designed to run on it. I can't think of any reason why premium fuel would be the problem, but I have heard stories of premium fuel doing weird things in engines not tuned for it, so you never know. Either way premium fuel isnt really doing much for you unless your engine is tuned for it.
 
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