NvMySi

Hey guys, so I bought a 08 TL-S 6speed manual, I scanned the engine light and have the following codes:
P0301 Cylinder 1 Misfire
P0302 Cylinder 2 Misfire
P0304 Cylinder 4 Misfire
P0305 Cylinder 5 Misfire
P0300 Random Misfire
P0430 Catalyst System Bank 2
P0420 Catalyst System Bank 1

any help would be appreciated, thanks

peter6

Couple possibilities that come to mind:
- clogged cats - drive the car, does car rev high, produce power over 4k rpm? Or put pressure gauge instead of upstream oxygen sensor, at idle it shouldn't be above 2 psi
- bent valves - it's 6mt so it's possible to money shift and over rev the engine, if that is the case it usually misfires at idle and works decent on higher rpm, it will make some power at higher revs. To be 100% sure, compression test and leak down test.
- since we don't know the history of the car, maybe engine is out of time or timing belt broke on it before? Do comp and leak tests

NvMySi

Thanks Peter I will try it next week when it warms up as it’s cold up here in Canada, I noticed the center cat is removed just under the shifter area looks like just a test pipe is installed, also the exhaust fumes are strong smell. Would that have anything to do with it? I will check plugs and coils first, while I’m at it I’ll do comp test, I can’t do leak down as I don’t have the tools for that.

peter6

If you have compression tester, does it have standard air fitting connector on it? If so just use pressure regulator and connect it to air compressor and try to hear / feel where is air coming from. There should be some videos on youtube how to do that. Might need to rotate the engine to make sure that valves should be closed.

stokesey

I had those exact codes on my 08 TL. compression test showed blown rings on cylinder 1. I had the ring set in hand when folks here advised me to just purchase a JDM engine and swap. $900 for a clean engine with 70k on the clock from Japan.

But don't let me scare you. Do compression test before you draw any conclusions !

My first acura2020

you need to put new ignition coils and sparksplugs

truonghthe

Does your O2 sensor working properly? bad O2 sensors will lead to misfiring code. The basic 1st, how does your spark plugs and coils looks? have you inspected this forehand?


If spark plugs are new and coil are good (no crack) then you can follow as below.

You can troubleshoot this by clearing the code then go for a test drive, put the car in 3rd or 4th gear then apply about 75%-100% if the car misfiring under load this is cause by bad O2 sensors. At this point I WOULD NOT worry about compression and leak down test JUST YET.

Pair of TLs

You BOUGHT it with those codes?
At least #3 & #6 are good, right?

Does it run, run badly or what?
Follow the advice ^^^^

A smelly exhaust is bad, mkay?

sdsbama

I had issues like this on my 05 TL, turns out it was the gas from Shell caused all the issues. I switched to BP and it never came back again. Good luck