Hi guys

Why does intermittent misfire occur?
Does the TCS light turn on but the TCS does not work?
Could a certain cylinder misfire occur due to a defective fuel motor?

Misfire occurs between several minutes and several tens of minutes after starting, causing the engine warning lamp to appear or the engine warning lamp and tcs to appear together.

If you check it with a simple scanner
Between minutes and tens of minutes after departure
P1399 is detected and the engine warning light does not appear. (Checking it says it's a random cylinder misfire.)
If you keep driving a little longer
Only engine warning light or engine warning light and TCS light appear at the same time, and 1 or 1,4 or 1,2,4 misfire is detected by the scanner.
Most often, only 1 or 1 or 4 occurs.
After erasing with a scanner, it does not float for a while.
Then it will pop up again the next time you drive.

The spark plug and ignition coil were all replaced.
The engine's idling condition is very good. It is said that compression pressure will not leak in the workshop.
I tried using WURTH contact spray on the terminals of the ignition coil and the ecu on the passenger side, but it did not change.

While driving, misfire does not occur continuously, but once or twice. Why is this?

 

Sounds like it could be a coil problem. I had similar symptoms, codes, and CEL+TCS lights, turned out to all be from one bad coil.
I even noticed there is a difference in engine firing with non-OEM coils. I replaced that bad coil with a non-OEM coil and the engine worked fine with no CEL, but every so often it would buck slightly at idle and low-end acceleration. Eventually swapped out the non-OEM coil for an OEM and the problem went away.
That being said, did you use NGK plugs and OEM coils? Double check your spark plug gaps and inspect the coils for signs of a defective boot (especially if non-OEM, those things suck). These engines freak out when there is even just one misfire, so I'd start by focusing on CYL1.
If all the gaps are good, you can even try switching around some of the coils to see if the codes follow the coils. Maybe try using some dielectric grease if all else fails. Good Luck

 

Thank you.

Spark Plug All New NGK-PZFR5F-11
All new ignition coils NGK 48841
Is it necessary to replace the ignition coil with OEM again? It is a lot expensive.
The EGR valve has also been replaced.

Some say it is because the cylinder's compression pressure is leaking,
Some people are called ecu's bad guys,
The form of engine noise and exhaust gases is very good.

Thanks for the advice and I'll give it a try.

 

I had random misfires but only after the car had been driven for 30min - 1 hr and starting it after it had been sitting for a bit. I ended up replacing all coils and plugs, cleaned the EGR, and valve cover gasket replacement and those all didn't help and costed me a lot(coils mostly). Ended up finding this thread after all that https://acurazine.com/forums/second-generation-tl-1999-2003-98/2000-acura-tl-multiple-misfires-when-starting-953177/ and it seems like I had a heat soak. I haven't done any of the mentioned 'fixes' in the thread but I know its a heat soak for sure now.

However if you're having this on cold start then this is probably not your issue lol.