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Discussion Starter #1
I recently embarked on replacing cam seals and I believe in the process of removing the VVT-i gear, I added some stress to the inner o-ring to where the car idles like shit. Plus the car having nearly 250k miles is contributing to it. It also sprays oil all over the place when throttle is applied

My question is, is that lack of oil pressure enough to cause the shitty idle?

If it is, I'll need to order a gear from PHR, they seem to have an alright deal on a remanufactured and painted unit.
 

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I recently embarked on replacing cam seals and I believe in the process of removing the VVT-i gear, I added some stress to the inner o-ring to where the car idles like shit. Plus the car having nearly 250k miles is contributing to it. It also sprays oil all over the place when throttle is applied

My question is, is that lack of oil pressure enough to cause the shitty idle?

If it is, I'll need to order a gear from PHR, they seem to have an alright deal on a remanufactured and painted unit.
Yes, low enough oil pressure will cause issues. Powerdynamix rebuilds the VVTi gears if you do not want to do it yourself. I is cheap and he does a great job. I had some done by him and painted too.
 

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Discussion Starter #3
Yes, low enough oil pressure will cause issues. Powerdynamix rebuilds the VVTi gears if you do not want to do it yourself. I is cheap and he does a great job. I had some done by him and painted too.
I ended up ordering the Viton seals. When the engine gets past 2.5k rpm, oil really starts to sling everywhere. However, once past 2.5k rpm, the engine starts to act normally compared to the really shitty idle, ~450 rpm

The repair is quite simple provided I follow the video instructions to a tee from all the ones that are on the internet.

I really hope that is the issue. I don't know if you recall I had made a recent post about needing an ungodly amount of torque to break the bolt holding it on. I am hoping I just ruined the seal. And if not the seal, the gear. Because I really don't want to replace bent valves if that's what I did when it finally broke.
 

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Discussion Starter #4
Yes, low enough oil pressure will cause issues.
So due to time constraints I had to bite the bullet on getting a new assembly from toyota, not ideal but I can't really go back now. Installed brand new gear.

Idle is still bad, with driving power extremely down. Torque is practically non-existent. However I was not getting any codes before I installed the gear. But now I am getting multiple misfire codes. I'm hoping to check the coils and wires and find a loose one.

I plan to do a compression test maybe tomorrow to see if any cylinders are down on compression resulting in bent valves.

Any suggestions would be greatly appreciated!
 

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Discussion Starter #7
Sorry to say. But did you re-due the timing belt correctly?
I followed the correct re-timing procedure. Set both cam gears' notch (not the dot) to TDC, and have it be aligned with the metal cover notch. Then because I do not have the OEM crank pulley, I must remove the aluminum one and base my timing off the crank gear. Which has an equivalent notch at TDC. Then align that with the dot on the block of the engine.

Because I am trying to get the vehicle running correctly quickly, I had it inspected by a shop, and the technician before tearing into the engine said "oh it sounds like a timing issue, definetely a tooth off". Hours later he comes back to say: "oh your timing was spot on, perfect. It has to be the VVT-i gear, it's slinging oil everywhere."

Of course it was a failed diagnosis and I didn't pay them a dime for the running around and not telling me exactly the correct problem.

I was thinking the same thing, if the belts off by a tooth or 2 it will do something like that. :cautious:
The only error I think I could have is being off by within a millimeter of timing, which due to the timing belt's teeth being so large, the timing will slip into the nearest correct tooth. Provided I set the crank to exactly where it needs to be, which as stated above, was done with the gear.



To be clear the engine runs like normal and smoothly once I give it some revs. Hoping I screwed up a coil or something, I don't know.

Thanks for the comments guys, any troubleshooting is welcomed. :D
 

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Discussion Starter #9
When doing the timing. Did you check the teeth on the timing wheel? Other than that. I would say go back over the connections and check compression with fuel.
I'm not sure what you're referring to with the "timing wheel". When looking at the teeth for said timing wheel, what aspect should I be looking for?

I'm about to get started on compression and a spark check in about an hour. I'm not quite sure how I would ensure proper fuel delivery; however I will go back and check all of the fuel injector connections and reseat them.
 

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Just to be clear i wasn't doubting you had done it correctly, just suggesting it does sound like what happens when its off by a tooth on one of the cams. ;)

I think Solaryellow is referring to the timing wheel or teeth on the back of the timing belt pulley on the crank. If its damaged a tooth, which is apparently easy to do when removing to change the crank seal, the timing wont be getting the correct firing order. Again its only a suggestion.

In my limited experience rough idles that perk up when the revs get above 2k are usually cam gears off, ignition timing off, or maybe coils and injectors not operating correctly. As the revs build the more cylinders you have in an engine the more it is able to mask a cylinder not working correctly (1 out of 4 cylinders is easily noticeable, 1 out of 8 is harder), so if its not idling it may not be firing at higher revs but the momentum of the engine spinning masks a lot. Would also explain any loss in power or torque.
 

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Discussion Starter #11
Just to be clear i wasn't doubting you had done it correctly, just suggesting it does sound like what happens when its off by a tooth on one of the cams. ;)
Haha, right, right. I just wanted to be clear of how and what I did to let anyone know who chimes in to know the procedure was done correctly. And if what I described was incorrect, then I could then be corrected.

I think Solaryellow is referring to the timing wheel or teeth on the back of the timing belt pulley on the crank. If its damaged a tooth, which is apparently easy to do when removing to change the crank seal, the timing wont be getting the correct firing order. Again its only a suggestion.
So this is another instance of people that I've heard talking about the "timing pulley". Is everyone just referring to the crank pulley as the timing pulley? And if so, I'm not sure how, let alone which part, could be damaged. I did change the front main seal, so that part of the engine did have to be removed. However, the crank gear seemed fine, slid on and off like it should.

The only weird part that a friend and I noticed was this piece of metal that bends as you pull the gear off the crank, if you've done this procedure before, you should know what I'm referring to. And when you go to put the gear back on, I just slightly tapped it back to how it looked when I found it.


In my limited experience rough idles that perk up when the revs get above 2k are usually cam gears off, ignition timing off, or maybe coils and injectors not operating correctly. As the revs build the more cylinders you have in an engine the more it is able to mask a cylinder not working correctly (1 out of 4 cylinders is easily noticeable, 1 out of 8 is harder), so if its not idling it may not be firing at higher revs but the momentum of the engine spinning masks a lot. Would also explain any loss in power or torque.
I'm leaning on I hit a coil or something when I tore into the valve covers and unseated something. I re-did the wiring about a year or so ago, so its not really old, albeit not brand new. But the masking a cylinder not firing with momentum idea certainly makes sense. However, there is a chance I need to quickly learn how to replace a damn valve or two :cautious:

I still have yet to tear into anything like I said, but I spent time to get all the tools required and I'll be digging into it shortly.
 

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Discussion Starter #12
...or maybe coils and injectors not operating correctly.
So after taking a dive into the engine bay, I've discovered pistons and spark plugs 3 & 6 covered in what I can only imagine would be fuel.

I also checked SP gap, and the highest variance was 2 thousandths of an inch, which I don't believe would be enough to cause the issues I'm seeing here, but maybe I'm wrong

So I'm guessing its coil related, seems like the injectors are doing their job haha.


I've not conducted the compression test, but it's getting late and I'll just pick that up tomorrow
 

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So after taking a dive into the engine bay, I've discovered pistons and spark plugs 3 & 6 covered in what I can only imagine would be fuel.

I also checked SP gap, and the highest variance was 2 thousandths of an inch, which I don't believe would be enough to cause the issues I'm seeing here, but maybe I'm wrong

So I'm guessing its coil related, seems like the injectors are doing their job haha.


I've not conducted the compression test, but it's getting late and I'll just pick that up tomorrow
Or a leaking injectors.
 

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So this is another instance of people that I've heard talking about the "timing pulley". Is everyone just referring to the crank pulley as the timing pulley? And if so, I'm not sure how, let alone which part, could be damaged. I did change the front main seal, so that part of the engine did have to be removed. However, the crank gear seemed fine, slid on and off like it should.

The only weird part that a friend and I noticed was this piece of metal that bends as you pull the gear off the crank, if you've done this procedure before, you should know what I'm referring to. And when you go to put the gear back on, I just slightly tapped it back to how it looked when I found it.
Its a weird tab, apparently to try stop the timing gear coming off if the pulley ever comes loose. There is a M6? screw holding it on which you are supposed to take off first, if you try and pull the pulley past it you can damage the timing teeth on the back of the pulley. I just had mine off for the timing belt yesterday.

Have a look at posts 7 & 8 on Help, please -- messed up timing belt job - ClubLexus - Lexus Forum Discussion.

You can see on the photo of mine below the red arrow is the tab to remove, the blue arrow is the timing teeth that can get damaged and the green is the obscured sensor that reads the teeth for the timing position.
133843
 

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Discussion Starter #18
Its a weird tab, apparently to try stop the timing gear coming off if the pulley ever comes loose. There is a M6? screw holding it on which you are supposed to take off first, if you try and pull the pulley past it you can damage the timing teeth on the back of the pulley. I just had mine off for the timing belt yesterday.

You can see on the photo of mine below the red arrow is the tab to remove, the blue arrow is the timing teeth that can get damaged and the green is the obscured sensor that reads the teeth for the timing position.
Well ill be, there was a bolt that held that thing in. I never saw it. However I do not believe I damaged the timing teeth, but I don't know the tolerances for the sensor. This could be the source of the problem. I knew the crank angle sensor existed, just not how it worked. Although wouldn't I be getting a code saying the sensor is having problems?

I finally got around to doing the compression test, and all 6 cylinders came back with flying colors! all near 200 PSI and less than 10% variance cylinder to cylinder :D

However, I think I might have faulty coil packs. I got the cheap ones on amazon, and did the job April 2018. I'm not sure if getting another set, or just going OEM would be a good move (really not wanting to spend $600+ on fucking coils). I know they can be tested, although I don't know what the resistance is supposed to be for our coils. And even if the resistance comes back ok, I need to verify spark. I tried doing this by myself, and wasn't able to get any good results.

There is even a chance I messed up the procedure, since i've never done this before and ruined one or two of them.
 

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have you still got any of the good coils from before you swapped them out? If so you could try swapping one or 2 back in to test a cylinder or 2 at a time, through all the cylinders eventually to see if it fixes anything. I would have thought typically a coil pack would throw a code as well, but i could be wrong. What about the igniter? I don't know much about them either but would imagine that could give it ignition issues.

Not sure if the teeth on the sensor would throw a code or not, to be honest apart from the regular stuff im not sure what throws codes and what wont.🙄
 

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Discussion Starter #20
have you still got any of the good coils from before you swapped them out? If so you could try swapping one or 2 back in to test a cylinder or 2 at a time, through all the cylinders eventually to see if it fixes anything. I would have thought typically a coil pack would throw a code as well, but i could be wrong. What about the igniter? I don't know much about them either but would imagine that could give it ignition issues.

Not sure if the teeth on the sensor would throw a code or not, to be honest apart from the regular stuff im not sure what throws codes and what wont.🙄
Funny enough before I read any of your response I went to my remote garage and picked up the old ones to test this exact theory. I didn't know if I had the OEM Toyota ones or not, but to my surprise, I did have them. However, I replaced them for a reason, so I don't know if they'll work, but worth a shot.

I also purchased a coil pack testing tool to verify spark as well. So we'll see what the results are probably sometime tomorrow. It'll be such a pain going back and forth but I gotta do what I gotta do.

As for the igniter, oh boy, what a damn pleasure it is working with that. Over the past year or so, I've been dealing with it not working once in a while. Turns out due to the car going through so many heat cycles, the connector for it becomes so brittle and was slowly deteriorating. Thus causing one of the wires to become loose and not work right. Not to mention all the other shit in our engine bays that become brittle due to excessive heat cycles and break :cautious:.

I don't believe i'm running into an issue with the igniter though, since the only issue I just described is more of an all or nothing case, where either the engine turns over, or not at all.
 
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