[jlmeyer52]

Hello, I'm a new user to this, but I've had my 2000 GTS for about 7 years. I'm having some noise underneath my valve cover and it seems to be localized near the timing chain area. It only occurs sometimes when my RPM's are under 2K and decellerating. And I can make it stop by feathering the throttle a bit. Basically sometimes it happens and sometimes it doesn't but it definately happens everytime I drive it. Also it only happens after the engine is at normal opperating temp.

Here is some history on the car. I had major engine failure about 2 years ago after a connecting rod failed, and bought a remanufactured engine. This engine had an oil consumption problem from the start and I ended up having it rebuilt just a week ago. However, this noise has been there the past two years intermittently, and only recently after the rebuild has started happening more frequently. The company that did the reman assured me that the timing chain was new, and tight so I don't see this being the problem. I'm thinking it could have something to do with the VVT controller assembly possibly because they did not replace that. They just tested it, and told me that it was mechanically sound.

The only engine code I have gotten is P0300 which is just a random misfire code. As far as I can tell the VVT system is working although I haven't got it into lift range yet as I'm still breaking in the engine and don't want to put that kind of load on it until after 500 miles.

Last, I've put about a hundred miles on so far, and my oil has dropped maybe an eighth on the dipstick. I'm hoping this is just due to the engine breaking in, but I'm a little concerned the consumption problem hasn't been solved with the recent reman.

Any suggestions would be great. I'm going to test the solenoid for the VVT soon to rule that out, but after that I'm really not sure what to do. I love this car and would hate to have to sell it, especially after investing so much money into it.

 

[homeworld1031tx]

What type of noise is it? If you actually think it is the timing chain itself, then it is worth removing the cover and inspecting the chain tensioner which is on the rear side of the head - it's easily visibily and you'll know what it is when you see it. As for the VVT assembly not working i'm pretty sure you would know from a CEL. The OCV that controls the VVT actuator has quite a few codes associated with it. Don't rule it out though.

As for the oil consumption problem, they probably honed the cylinder walls which is something you're not supposed to do for a 2zz motor because of the liner that is on the cylinder walls. Call the shop that built the engine and see if they honed it (be slick about it and ask them if they honed it rather than saying 'you're not suppoesd to hone it, did you?'). If they did, you're going to be drinking oil forever.

Did you have an oil consumption problem before this rebuild?

 

[Pool Playen Bob]

Call the shop that built the engine and see if they honed it (be slick about it and ask them if they honed it rather than saying 'you're not suppoesd to hone it, did you?').

this ^ really have to play it off as if they didn't well then they effed up. make it sound like it.

but i'd call them up before cracking anything open on that engine. valve cover too even to inspect. because if you don't get permission they could simply be dicks and say you tampered with it. valves may need adjusted too. could be crazy stupid possibilitys from rebuilds.

 

[jlmeyer52]

The noise seems to start out kind of like a ticking sounds and then gets louder to more like a rattling noise like a marble in a tin can. Then I just feather the throttle and it goes away imediately after 2000 RPMs. Then it starts again sometimes, and sometimes it doesn't. I could record it probably, actually I think I will and link it in.

As for the oil consumption, it started 2 years ago when I bought the remanufactured engine. When they rebuilt it recently I am positive that the remachined the bores and put new pistons and rings in, because they mentioned that the bores were scored, but had relatively good clearances when they took it apart. So, are you guys saying that you're not supposed to do that with this engine? Or is there a right and wrong way to bore it out?

 

[homeworld1031tx]

You are not supposed to bore the cylinder walls at all - if they are scored you need to resleeve them, you can't repair them. So yes, your car is going to be sucking down the oil pretty enthusiastically :/ .

I'm not sure what the ticking noise is... maybe one of your lifters/rocker arms could be damaged? someone with more knowledge needs to give you some input

 

[jlmeyer52]

Hmmm.. that's definately not what I wanted to hear. There is a chance that they sleeved it, I'll ask them and see what they say. Hopefully they did it correctly.

Thanks for the info.

 

[Smaay]

too bad you didnt find this site first before you spent alot of $$$. yes find out if they sleeved it, didnt you get a BOM or invoice of what they did? read this thread and look at the pics at the end

http://www.newcelica.org/forums/showthread.php?t=324650

 

[jlmeyer52]

Yeah I should have definately checked here first, but unfortunately I just figured they new what they were doing. The good thing is that the company gave me a 3 year warranty with this engine, and this recent rebuild was done for free. The warranty still goes until June, so if it continues to consume oil I'll push for them to sleeve it. I'll have to look at the invoice they gave me tomorrow and see what it says. Maybe I'll get lucky and it will say they actually did sleeve it afterall.

I think I narrowed down the noise to the vvti controller assembly, which is also under warranty, but I'm going to make sure the OCV and filter is clean first before I have it looked at. If they end up having to replace the vvti controller, do they have to remove the timing cover, or can they just remove the tensioner and slip the chain off the sprockets?

 

[jlmeyer52]

Just in case anyone wanted further reading into the VVT-i system.. the following articles seemed pretty helpful.

http://www.motor.com/magazine/pdfs/062010_04.pdf
http://www.motor.com/magazine/pdfs/042010_04.pdf
http://www.motor.com/magazine/pdfs/052010_04.pdf

 

[homeworld1031tx]

That's a neat website/magazine, thanks for the links.

i would imagine that you just need to remove the valve cover - it is possible to change cam shafts without removing the timing chain cover.

 

[donteatbugs]

it may be piston slap from a loose fit in the bore that you are hearing in the top end. i had this problem once and it would go away after about 3k rpm and my car burned a little more oil too.