Engine knock at cold start (1 Viewer)

[BReynolds]

Didn't know if anyone else has experienced this. When starting in the morning, there is a knock for about a second or two then goes away. I've never had a Toyota make this noise and was wondering if anyone has.
It's a 2003 lx 470 with 142k.

 

[TexLexican]

Didn't know if anyone else has experienced this. When starting in the morning, there is a knock for about a second or two then goes away. I've never had a Toyota make this noise and was wondering if anyone has.
It's a 2003 lx 470 with 142k.

Isn’t that a symptom of a loose spark plug?

 

[BReynolds]

Isn’t that a symptom of a loose spark plug?

It sounds like its in the bottom of the motor. I wasn't sure if other people have had this issue or it was just poorly maintained. Oil pressure is about at a quarter at idle and seems to be typical from what I'm finding out.

 

[GVegasG]

Check spark plugs - perhaps just tighten it to like 18ft lbs.
Also check for exhaust leaks using vacuum and soapy water or using smoke test.

 

[clx16]

Sounds locations are hard to track down. But second or two.....sounds like dry top end on startup... my experience has been bad/cheap oil filters that let the top end drain back to dry overnight.

 

[BReynolds]

Sounds locations are hard to track down. But second or two.....sounds like dry top end on startup... my experience has been bad/cheap oil filters that let the top end drain back to dry overnight.

I changed oil last week and used a wix filter. Gonna get a Toyota filter and see what happens.
Thanks!

 

[clx16]

no experience with Wix, They have a bad rep in the 80 section. I use toyota now, but first toyota vehicle I had, one oil change and that was the last time i used a Fram. Didn't have issues with mobile 1, but did with K&N. In short all my vehicles can use the same filter now and toyota filters are cheap so i just order in bulk.

 

[TexLexican]

no experience with Wix, They have a bad rep in the 80 section. I use toyota now, but first toyota vehicle I had, one oil change and that was the last time i used a Fram. Didn't have issues with mobile 1, but did with K&N. In short all my vehicles can use the same filter now and toyota filters are cheap so i just order in bulk.

I’d also be careful with Walmart supplied filters. They cheapened out on their K&N filters since it doesn’t have the built in tightening nut. The housing is a substantially different material than one you would buy from Autozone. Who knows about the actual filter material.

It’s been known that in order to stay within Walmart’s prices, suppliers have to cut costs where they typically wouldn’t to begin with. Appliances are common items where this happens. Hopefully oil isn’t a victim of this too.

 

[Eicca]

I’d also be careful with Walmart supplied filters. They cheapened out on their K&N filters since it doesn’t have the built in tightening nut. The housing is a substantially different material than one you would buy from Autozone. Who knows about the actual filter material.

It’s been known that in order to stay within Walmart’s prices, suppliers have to cut costs where they typically wouldn’t to begin with. Appliances are common items where this happens. Hopefully oil isn’t a victim of this too.

Oil itself seems fine. I get my 20k-mile full-synthetic Mobil1 from Walmart and it comes out of my 3UZ at around 8k miles (one year’s time) looking a nice light caramel color. I’m tempted to extend the interval to two years. But in the end, oil once a year is cheaper than an engine.

 

[clx16]

I changed oil last week and used a wix filter. Gonna get a Toyota filter and see what happens.
Thanks!

Did you have this issue previously or is this a new to you vehicle? and you had the issue before the oil change?

 

[BReynolds]

Did you have this issue previously or is this a new to you vehicle? and you had the issue before the oil change?

It is new to me. I didn't get to cold start it before purchase. I changed the oil filter this evening and will see what it does in the morning.

 

[Makakio]

Piston slap. Very common on the 4.6 - noting to be done but then again, not a problem per Toyota. These motors go 400k miles with it. Mine has gone nearly 200k so far.

 

[BReynolds]

Piston slap. Very common on the 4.6 - noting to be done but then again, not a problem per Toyota. These motors go 400k miles with it. Mine has gone nearly 200k so far.

I changed plugs, did a BG's EPR engine flush with the MOA additive and noise has pretty much stopped. Not sure exactly what it was but think the MOA helped a lot.

 

[4Beast]

Are you sure it's not an exhaust manifold crack? A lot of the time they present more as a knock than the traditional "tick," and go away after a few seconds, once the manifold heats up and expands.

 

[Mike NXP]

Didn't know if anyone else has experienced this. When starting in the morning, there is a knock for about a second or two then goes away. I've never had a Toyota make this noise and was wondering if anyone has.
It's a 2003 lx 470 with 142k.

Don't be too concerned, mine and many others I have heard have a bit of a chugging / knocking / loaded sound in the beginning. I used to panic and think it was starved for oil or something but IDK...... I suppose it's not ideal but as long as you check everything over and are using the proper oil and what not you should be fine.

Glad to see you solved it, seemingly, for now =]

 

[BReynolds]

Are you sure it's not an exhaust manifold crack? A lot of the time they present more as a knock than the traditional "tick," and go away after a few seconds, once the manifold heats up and expands.

I don't think so but can't say for sure. The sound pretty much went away after I did the service I described above. I've built engines for muscle cars
over the years and am somewhat mechanically inclined. With that being said, I'd like to see better oil pressure as at idle its a hair under the quarter mark.
From what I'm learning, that's normal.

 

[Dilspec]

Sounds like piston slap to me, which my 2003 100 series had, also at 143K. My friend put 35k+ miles on it with no issues.