Car misfiring and shaking after going to the store

I went to a grocery store and went shopping for about 20 minutes. When I got back to my car and started it up it started to misfire and sounded like a thrown rod. The car was vibrating like crazy and I recorded it on my phone to demonstrate the behavior.

This has happened before and I took it to the dealership and they suspected it was spark plugs since they are the original plugs, (90k miles). I didn't get the car diagnosed because the issue went away when I brought it to the dealership--so I drove home. With that said I replaced the spark plugs and noticed oil on the threads. I replaced the plugs and ordered a valve cover gasket which I was planning on installing this weekend. I originally suspected the oil was causing this misfire.

3 weeks later, today, l encountered the issue again so I recorded a video! I noticed the check engine light will flash and then turn off and when the car cools down and the check engine light goes out and the car runs like normal.

It would seem like a component is failing but I don't know what the issue is. Does anyone have advice?

Here's the video I recorded today:

 

The car is a 2nd gen with 90k miles. Also I researched that there isn't a physical EGR valve in the car. I was reading that the EGR is set digitally by the ECM.

I'm facing issues scanning the code because the check engine light goes out and completely disappears. I don't know if I can view history codes but I don't have a scan tool. If there's not active codes would the part stores still be able to read the codes?

 

No oil burning yet and no coolant loss

 

I did the valve cover gasket today and ordered some coils yesterday. I used the great FIPG instead of the RTV since I want to do this right. I did wait a few hours and did a test run to see if the car would have the same misfire. Unfortunately after changing the plugs and the valve cover gasket the misfire did showup today after I went to the market again. It starts fine but intermittently does not like starting hot. I'm hoping the coils fix it otherwise the next thing to check would be the injectors I suppose.

I reviewed the thread you posted and saw inspiration in the Autel MaxiAP AP200! I ordered one and it should be here tomorrow.

Yes. When I changed the plugs I also swapped out the PCV since it was only ~$10.

Just an update but I've finished the valve cover gasket and now the total changes are:
1. New oem sparkplugs
2. New oem PCV valve
3. New oem valve cover gasket
4. Cleaned the MAF and throttle body

Bonus: Ordered the Autel MaxiAP AP 200 scan tool
---------------------------------------
After waiting for the FIPG to dry for 3 hours I went to the market to see if I would have the same issue and unfortunately the issue still remains. This time I put the coils in a different order and I noticed the misfiring disappeared faster this time.

I have new oem coils coming in the mail from my local dealer and they should be here Tuesday. In the meantime I can only suspect the fuel injectors may have some kinda issue next. Before I load up the parts cannon I'm hoping the scan tool comes soon so I can see what the historic codes are and get a better idea why the car is acting this way.

- Fart

 

So the Autel scan tool came in and I have pending codes from the hot start. I have a P0300 which is a random/multiple cylinder misfire and the suspects are Cylinder 2,3 and 4. I wonder if when the vehicle is sitting after it was running something floods these cylinders. The issue goes away after the car runs so something must be flooding the cylinder or the drive cycle on a hot start is different from a cold start.

Either way the issue is easily repeatable by hot starting the car. On Tuesday when the coils come in I will check again. I can't help but think maybe there is actually something serious going on. It would seem like something is flooding the cylinders while parked. I do not know if I should take it to the stealership as I am not the most skilled and the parts cannon is running out of parts.

I did see a write up of someone taking out the fuel rail without removing the valve cover. I don't really want to remove the valve cover as I just did the valve cover gasket.

The old PCV looked good still rattled there was oil and some carbon deposits on the outside but it was still functional.

 

Did you buy all new OEM injectors or did you get them cleaned by Rich?

Injectors from my dealership near me are $134 each. I did a quick ebay search and found some interesting things: https://www.ebay.com/itm/403578803740 for only $50.00 you can get FOUR. This seems like a fake/cloned part since the dealership is $194.58 MSRP for one injector.

Then here's this guide which links to this: https://www.ebay.com/itm/121312381714 which are remans which seem legit. The guy who made the guide had good results.

Both claim OEM one being reman but I wonder what I can do because it doesn't really feel good to spend $500.00 on more parts. Maybe the remans can fix the issue temporarily and then I will know for certain what to parts cannon next time.

The part that makes me not trust is their "oem" part number. I can clearly look it up on Toyota and it says the part number is this:

Part Number: 2320921020
Supersession(s): 23209-21020

Yet the part number 23250-21020 does not show up in the Toyota database. I can't find a clear manufacturer but I'm assuming it's from China and not Japan. 23250-21020 23250-21040 23250-21060 Fuel nozzle Injector for Toyota LEXUS - IBUYautoparts.com

 

Just an update I changed the coils and none of them looked bad. I tried to create the issue and all was well for a few days but on a hotter day I was able to reproduce the issue.

While I waited for the coils to arrive I preemptively ordered the ebay reman injectors from Atlanta Auto. Today I did the fuel injector procedure and while removing the old injectors I noticed they were not OEM and instead were some remans as well! It was quite a shock because I planned on the injectors already being OEM so I could get them professionally cleaned by Chuck.

Now that I don't have OEM injectors I'm not going to clean the old ones. These are basically junk to me.

Picture for reference: https://i.imgur.com/vyJlLxT.jpg

Looks like whoever did this job before used silicone grease instead of oil or gasoline. I used oil this time since I didn't have a can of gas laying around.

I decided to measure the resistance of the old injectors just because and 3 out of 4 were in the range of 14.6-14.9 ohms. The heavily silicone covered injector had a resistance of 27.3 ohms! This seems unusual and perhaps was why the fuel injector was failing under higher temperatures.

The re-manufactured injectors I just put in all had readings of 14.9 ohms so lets see how long that lasts.
The manual says:


If I encounter issues with the injectors I might just buy OEM injectors.

To close the issue for now the total parts cannon consisted of:

• new OEM spark plugs
• new OEM coils
• new OEM PCV valve.
• re-manufactured injectors

The cleaning list was only MAF and throttle body

Thanks everyone for the help!