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Hello peeps!
136898

April 2020, I bought my 06 IS350 with 200k miles. It's a great car with ample power and good handling. I have had some issues though.

I drove it until the engine threw a rod due to the 1st owner not changing the oil for the previous three years and using 87 octane instead of 91. It leaked, it burned oil. It was in bad shape.

It was replaced with a 100k engine which was immaculate, however I noticed on the very first day that there was an odd ticking noise coming from the passenger side valve cover that eventually turned into something like a jackhammer when coming to a stop. It sounded like a timing chain and I made multiple visits to the shop to have them diagnose and repair.
They did hear the noise I was hearing, but all they said was to change the oil, which I did, but the noise persisted. It seems all they have time for is to replace engines and nothing else.
Not too long before the 90 day warranty was up, I heard the engine knock under load (going to try another brand of gas) and then the engine developed a slight rod knock afterwards.

I decided since the shop doesn't want to deal with it anymore and I had a couple other issues that needed to be addressed, I'd go the DIY route and fix everything myself.
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While trying to get the subframe out, I went ahead and looked under the valve cover.
First, I found what looks to be a piece of silicone in the bottom screw of the VVT oil pipe. There was almost an excessive amount of silicone throughout the engine.
I found pieces in the oil pickup tube as well and spilling over into holes and O-rings near the edges of the pan.
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Then I saw this cam gear. It looks like something was gnawing on it, but I saw nothing near it that could have touched it.
The main timing chain is tight, but I checked the secondary chain going to the exhaust valve and it has about half an inch of slack when I pick it up. Is that normal?
I didn't see any wear on the valve cover, but I'll check again tomorrow. What do you think was causing the noise and wear here?
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As for the bearings, After about 4 or so days and a broken upper oil pan (I didn't see all the bolts and snapped the oil filter housing off trying to pry it off), I inspected cylinders 1-3 and 5-6 and they were fine, but Cylinder #4 was beat up pretty bad, yet there was barely any signs of damage to the crank, rod or rod cap, so I cleaned, lubed and put on the new pair.
Now I just have to buy another pan and wait...
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Glad to see you getting after it! Those bearings are shot! This is on the “new” engine that was installed by that shop?
Yes.
But this happened after a knock event (Not due to using regular octane, but a cheap brand of premium fuel), which prompted me to teardown the engine.
Right now I'm mainly looking at the passenger valvetrain to see what's slapping around and making all the noise.

1 I'm thinking the VVT wasn't getting enough oil because of that chunk of silicone that plugged up the line going to the solenoid,
causing it to freewheel. I didn't notice the noise when on throttle, but as soon as I lift off, it starts clacking,
So oil pressure may have been sufficient enough to run the VVT normally except when coasting.

2 The secondary chain isn't as tight as the main timing chain and it may have been slapping against the valve cover or the plastic that it sits on.

The engine was making this noise from day one and they kept asking me to change the oil each time I brought it back (I had already done that).
That's one of the reasons I don't find the shop reputable. I found loose, mismatched and missing bolts and parts in various places, including a loose Transmission bolt.
They broke a connector on the transmission, which made the torque convertor slip and 4 forward gears to work instead of 6.
They even used the wrong coolant (Green coolant instead of the Red/Pink Toyota Coolant).

As long as I can turn a wrench, I'd rather not have a shop touch my car from now on.
 

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With bearings like that i would be concerned over the rest of the engine, make sure the oil ways in the crank are nice and clear before putting new ones in. What are the cylinder bores and pistons like? :oops: That must have been a hard 100k miles

Any chance the timing cover was loose or not installed right and rubbing on the cam gear? Marks like that almost look like the chains jumped off and rubbed on it but that would be catastrophic if its an interference motor like most are these days.
Otherwise possibly the cam gear could loose or assembled incorrectly so its out of center or something like that? But then you would normally just see the marks on one side of it.
 

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With bearings like that i would be concerned over the rest of the engine, make sure the oil ways in the crank are nice and clear before putting new ones in. What are the cylinder bores and pistons like? :oops: That must have been a hard 100k miles

Any chance the timing cover was loose or not installed right and rubbing on the cam gear? Marks like that almost look like the chains jumped off and rubbed on it but that would be catastrophic if its an interference motor like most are these days.
Otherwise possibly the cam gear could loose or assembled incorrectly so its out of center or something like that? But then you would normally just see the marks on one side of it.
I did re-inspect the top rod bearings and found they although they hadn't flaked or scratched, the thin top coating on the old bearings was completely gone in the middle and one had a tiny crack that my nail could catch on, so I replaced all the ones I saw that looked like that. I had done two oil and filter changes, went up in viscosity to keep the knock away for a little longer and drove it for a couple weeks to get essential items before I parked it and start repairing it. The filters did catch a lot of the bearing material and there was barely any in the pans or anywhere else in the engine when I tore down, but I feel like there's a chance that silicone could be somewhere else cause it was so easy to break off. I'm going to do a little more cleaning while I wait for new con rod bolts.

The engine appears to have been well maintained being so clean on the inside and having no sludge buildup on anything. Nothing wrong with the engine itself, just reassembled and put in carelessly.

As far as the timing issue,
I'm really gravitating towards that piece of silicone blocking the oil line enough to be causing problems with the VVT. I mentioned before, the noise is only when coasting or idling and goes away when the engine is loaded and has high oil pressure. I looked at different pictures of 2GR valvetrains and a few other Toyota engines with that VVT gear and they all seem to have that same mark on them for some reason. Also, the slack in the secondary is closer to 1/4 of an inch than half, which looks the same as the others I saw too. The slack is taken up when I rotate it, so I don't believe the really chain is an issue.
I did buy a couple lifters just in case it turns out to be those making noise, but hopefully clearing out that VVT line remedies it.

Thanks. Will have more pics soon.
 

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So I put everything back together last Wednesday and it was a success! It runs and doesn't leak oil, but there's still a problem.
I discovered today that I may have a bad oil pump, as I am barely able to stay above 10psi oil pressure at idle.
The engine is much noisier too and I'm concerned about starving the new bearings I just put in, so I've only driven it twice to get readings.
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I think the 'Low Engine Oil Level' light may have hinted something to me about it, but I still find that somewhat backwards, because I know there is a separate light for pressure
and the oil level has always been at MAX, but I never saw a oil pressure light.
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I don't know, but I'm thinking this engine had a bad oil pump since I got it back from the shop, That light flashed every time I drove it.
It's sad that these "mechanics" never thought to replace the oil pump while the engine was out. I bet they didn't even check it.

Well, I guess I have to go back in, and it involves the removal of the timing cover, so I have to figure out how to deal with that pesky A/C Refrigerant system, cause it's in the way.
Thankfully, I may be getting some assistance from another mechanic, so the process should be much faster.

Will keep you updated!
 
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