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I was hoping Eric can help me with this…
I recently acquired a ’98 Sienna and aware of the tapping noise. I thought it was the timing tensioner so I decided to change the timing belt, water pump, tensioner, idlers all the way through valve covers and cam/crank seals.
When I was done, I was disappointed because the noise is still there.
I think the noise is coming from the rear valve cover near the firewall, I am assuming it could be needing a valve adjustment? What do you guys think?
Here is a video, note that it does not have a check engine light on.
http://www.youtube.com/watch?v=_LvEUuDXCY4
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[quote=”ToyotaKarl” post=66463]
The IAC is on the left side of the plenum right above the PCV valve and the EGR valve is on the right side of the plenum… Take a good look at them and the PCV hose.
Also take a look at the rear exhaust manifold where it meets in the y pipe… Those go bad at the flex joint…. Also I have seen these burn through Exhaust donuts…
-Karl[/quote]
Karl,
Do these have something to do with the noise I mentioned?
If there is a leak in the Pipe from the exhaust to the EGR, it can cause an exhaust leak which makes a similar noise to a noisy valvetrain… It is really hard to see down that pipe when the engine is in the vehicle. A cracked EGR will make more of a scream…
The flex joint (on the Y pipe) will definetly give you an exhaust leak with a tick, as well as a cracked exhaust manifold or bad exhaust manifold gasket… The flex joints are known to go bad…
Worse comes to worse, you can temporarily add thicker oil to see if it goes away to verify the condition….. Then change back to 5-30.
Karl.
I was thinking if I messed up the timing or the previous person did, should it make tapping noise like that? I think when the timing is off it should give me misfire CELs correct? Just want to be clear it is not the timing problem.
To check the timing you need only to check the marks. However not trying to have a pissing contest or anything but it doesn’t sound like valves to me. Let me ask. Have you ran synthetic oil in the car? Doing this can cause the engine to sound like this. Well the good news is that the car drives fine and has good power. Unless you are willing to replace or rebuild the engine. Just turn the radio up.
One last thing Have you seen any metal shavings when doing the oil change?? Check for this. I recommend using a thicker oil. And some Lucas oil stabilizer. I have done this with my car, it will help with the noise a bit.
No shavings as far as I know.. when I took both valve covers off, the head is super clean. No sludge, literally the color is gold
If the timing was messed up by the previous belt installer you may or may not have an issue. FWIW this engine is a non-interference engine, thus the valves can’t be physically damaged by the pistons in case of a broken belt… Now the interesting thing that is going through my mind now is that I know exactly where the camshaft position sensor is on the front head, but for the life of me cannot remember seeing one on the back one….. Hmmmmmm…. I suppose it may be possible for it to be off on bank 2 without a CPS there to pick it up… The engine should not run well if it is off though…. AND You can easily re-check the timing marks by just removing the cover…
Another thing…I would hesitate to drive this car extended durations until you have figured out what the noise is caused by… I have driven in cars that had exhaust leaks (that you couldn’t smell) and have gotten a buzz and screaming headaches from the carbon monoxide…
Have you checked the exhaust yet?
With the exception of the sludge issue the 3.0 is a good reliable engine. If the valves are as clean as you say, I am really hesitant to think the valves need adjusted on the back and not the front though… This is why I wonder if the valves really need adjusted….
-Karl
I checked the exhaust near the firewall, seems like the bolts are all tight in its places.
I don’t really know exactly what to look for in that area.
You mentioned the EGR is on the right of the plenum, well I couldn’t find it. I don’t think it has one. I was looking for that when I was taking off the plenum, also TSRM says that too. Weird.
My 98 Sienna does not have EGR and no EGR VSV unlike this guy:
Pic below show my engine without EGR and VSV:
http://i1049.photobucket.com/albums/s384/Dennis_Lansang/20130711_081745.jpg
Hey mate,
It appears the pre 08 98 1MZ came without an EGR. I pulled up the toyota part reference catalog and found a difference in the manifold parts starting August 1998.
See here:
http://www.toyodiy.com/parts/p_U_1998_TOYOTA_SIENNA_MCL10L-PFSGKA_1701.2.html
I took off the plenum and rear valve cover in less than an hour:
http://i1049.photobucket.com/albums/s384/Dennis_Lansang/20130711_093338.jpg
A little tired and getting ready for work, will use feeler gauge to check clearances tomorrow.
[quote=”kkozlowski” post=66588]Hey mate,
It appears the pre 08 98 1MZ came without an EGR. I pulled up the toyota part reference catalog and found a difference in the manifold parts starting August 1998.
See here:
http://www.toyodiy.com/parts/p_U_1998_TOYOTA_SIENNA_MCL10L-PFSGKA_1701.2.html%5B/quote%5D
So I am good?
So before I took off the plenum and VC, I started the car once again and used a screwdriver as a stethoscope to hear that noise. I am really assuming that it is somewhere on that head area. I hope it is not on the block or else I’ll burn this Toyota! j/k
I little off topic here, I know I cannot reuse the intake plenum gasket and TB gasket. But since I have new valve cover gaskets, spark plug seals and camshaft seals installed already, should I buy another NEW set to install or I can just reuse the new ones that I just installed? Basically they have zero miles on them. I think I can reuse them, but of course i have to clean them up first prior to reinstallation. And in addition, they should not be damaged upon removal so I can reuse.
Any comments, suggestions?
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