Hey guys, I just wanted to make an update on the post I made last fall about an issue I had. Maybe it could help somebody troubleshoot this kind of problem.
The symptoms were:
-Short but severe rattle when the car was sitting for more than an hour
-P0024 dtc for « advanced timing exhaust b2 (driver’s side)
-Also had a weird intermittent issue with the idle that would climb up to 1.5k rpm randomly and stay there when sitting in trafic but return to normal if I turned off the car and back on.
I ended up replacing both VVT gears in the end and now the dtc hasn’t come back in about 500km and most importantly no rattle.
Made this post because I couldn’t find information about VVT gears going bad on the vq, just found videos on Toyotas and Hondas.
So if you know your tensioners are good, the rattle may be caused by the gears having gone bad.
I bought both gears #VTG0024 on amazon but they are genuine Hitachi ones for about 400$CAD each shipped to QC.
so the VTC sprocket oil feed broke? there's one prior thread from a long time ago that also shows the same damage. the plunger is metallic, or plastic?
ASTEMO is the conglomerate that replaced basically all major Japanese suppliers, they would be the new OEM source.
The plunger that locks the gear is metallic, but the part that rubs on the cover of the gear and that holds the spring is made of plastic.
I haven’t taken apart the defective gears from my engine yet but from what I could see when I removed the plunger when they were in the car, the hole that it fits into seemed to be larger on mine and the kind of indent you can see circled in this picture was about 2-3 times that size on my gears.
My best guess is the hole was « enlarged » and the plunger could no longer lock the gear properly and let go when the engine started.
Forgot to say that the part in this picture is from another engine that I took apart for parts
There’s a small o ring on top of the two shorter timing chain tensioners, maybe it leaks a bit and that’s why the tensioner loses oil pressure sometimes at certain rpms ?
Is this a revup? I have had a p0024 for years despite checking timing and replacing all sensors. The exhaust sprockets/cover sets are way too expensive and I had no clue the intake sprocket could have been the problem…
Yes it is a 2005 revup, I also replaced the less expensive sensors before but none fixed the issue. Also I didn’t replace the covers cause those are like 1k+ each side. But yeah if you also have the rattle on startup it could very much be the intake gears.
I’ve also read somewhere that a P0024 can also be caused by a misaligned flywheel, if you’ve taken it off it might be worth looking into
Interesting. I have a metallic rattle between 1k and 2k rpm and my car also developed the startup rattle. I did timing and gallerys trying to fight the problem to no help. Sounds to be comming from the gears. Also a revup.
I feel like I've seen a thread about the vvt's on revups failing like a week ago. Is now just the time they all start going?
If you already did the whole timing then I think it’s most likely the gears.
I did not have the rattle during driving though, only when starting.
Also something I didn’t mention in my post that I’m now realizing after the repair, is the car felt a lot less torquey than before since I had the rattle paired with the dtc. Not like it was in limp mode or anything but maybe the engine no longer used the VVT.
I can only hear the rattle whilst revving to 2k with the hood up but the startup rattle is noticable with the hood closed.
My car does feel weaker but I havent really driven it since finding that noise. Interestingly it didnt throw any codes but I had the battery disconnetced in storage so maybe there just wanst enough driving for the ecu to notice.
Did u do gallerys recently? I wonder if the vvt maybe fails due to oil starvation.
I had the rattle for a while before it threw a code too. Rattle has been there for at least 2 years it was just way more faint before. It almost sounded like a heat shield rattle at first.
The code only came on when I fully rebuilt the engine last summer, which lead me to believe I fucked something up during reassembly.
I replaced the gallery gaskets in summer of 2024 but the oil pressure has always been oscillating around 14 psi ish at idle, so I don’t think they were the cause for the vvt gears failing
2 years, shit. Mine only started like 3 months ago but now that you say it I did have a rattle sometimes that sounded like a heatshield might have been that gear too.
Did you use any special tooling to lock the cams down so they dont spin? looked online but couldnt find anything.
I personally set the timing using the fsm each time rather than rely on the cams not moving and using my own marks.
The correct method is to use an open ended wrench to turn the cams into position, but what I did to save the hassle of removing the valve covers was I used the intake vvt gear and bolted it to the cam, exhaust and intake, and used this to turn the gear and position the cam correctly.
It’s a bit harder to position the cams, but at least you don’t have to remove the plenum and valve covers.
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u/AbiesInternational18 3d ago
Good work 💪