Impossible TL Type-S Misfire
#162
Instructor
Thank u to all the new ops that chimed in .
Want to clear the air ,
First off the timing belt was never said to have been done ever , I just did it a couple weeks ago and there was no evidence that it was done , and the timing marks were spot on , job went smoothly we replaced all components .
This rough idle that I was trying to explain from day one , is NOT an idle issue . It is rough patch when u aple throttle from idle up in. Around 1500 rpms . it has never gotten worse or better .
as far as the missfires, I jumped on that due to a scanner that was used to see how the engine was running , yes it showed some missfires on a couple of the cylinders, ( I can almost guarantee u can all do the same scan and will find attest a hand full of missfires , clearly not an issue as there has never been an check engine light .
From day one a neighbour came over and took a look at my car and said he believes it's bad engine mounts / trani. Harmonic unbalance, thus giving the illusion of a miss fire , ( excess engine vibration )
I am now in the process of getting OEM replacement mounts and going this route .
My TL runs far to good to think that it's an interal problem , great power , pulls hard , amazing gas mileage, no pinging , ect . Not saying it's not possible, just really thinking I may have blown this thing a bit out of proportion .time will tell .
Fell free to chime in , anyone in coquitlam B.C want to meet up and chat , drop me a line
🍻
Want to clear the air ,
First off the timing belt was never said to have been done ever , I just did it a couple weeks ago and there was no evidence that it was done , and the timing marks were spot on , job went smoothly we replaced all components .
This rough idle that I was trying to explain from day one , is NOT an idle issue . It is rough patch when u aple throttle from idle up in. Around 1500 rpms . it has never gotten worse or better .
as far as the missfires, I jumped on that due to a scanner that was used to see how the engine was running , yes it showed some missfires on a couple of the cylinders, ( I can almost guarantee u can all do the same scan and will find attest a hand full of missfires , clearly not an issue as there has never been an check engine light .
From day one a neighbour came over and took a look at my car and said he believes it's bad engine mounts / trani. Harmonic unbalance, thus giving the illusion of a miss fire , ( excess engine vibration )
I am now in the process of getting OEM replacement mounts and going this route .
My TL runs far to good to think that it's an interal problem , great power , pulls hard , amazing gas mileage, no pinging , ect . Not saying it's not possible, just really thinking I may have blown this thing a bit out of proportion .time will tell .
Fell free to chime in , anyone in coquitlam B.C want to meet up and chat , drop me a line
🍻
#163
im having misufiring issues.
timing belt and related done 45k miles ago.
valve cover and plugs egr ports and valve cleaned 20k miles ago.
all good till recently misfires. Replaced one coil pack and still it’s the same. After reading ppls thread and seeing 0 solutions, I gonna take the cat off tomorrow since no one has reported doing that.
my valve cover gaskets r still leaking and last person did not use ngk plugs.
#164
wow first and foremost!
im having misufiring issues.
timing belt and related done 45k miles ago.
valve cover and plugs egr ports and valve cleaned 20k miles ago.
all good till recently misfires. Replaced one coil pack and still it’s the same. After reading ppls thread and seeing 0 solutions, I gonna take the cat off tomorrow since no one has reported doing that.
my valve cover gaskets r still leaking and last person did not use ngk plugs.
gonna replace VC gaskets again since person probably did not use oem gaskets.
#165
The guy also mentioned letting it run in reverse for 30 seconds or so before it threw the code on the #4 cylinder. I wonder if that would narrow it down for you, or at least add to the data you have collected so far?
#166
Latent car nut
iTrader: (2)
Who ever said turning by hand won't bend a valve is an idiot. It matters not the speed of the rotation, if the valves are incorrectly timed, a bent valves will be the result after only a single hand-turned rotation.
#167
Race Director
Still not buying it on an interference engine. You'd really have to honk on it once you hit an interference point to bend a valve.
#168
Latent car nut
iTrader: (2)
#169
Intermediate
Cold start misfire issue
08 type s auto 172k....Couple months now been dealing with this random cyl. misfire and cant figure it out. It runs rough at first start in the am for about 30 seconds if that and then it smooths out and purrs like a kitten. Or if it sits a lil while enough to cool the engine it will misfire. BUT ONLY ON START UP. As long as the engine is fairly warm it runs great. Things Iv done....new plugs and coils and fuel injectors,valve adj. and cleaned the hell out of the intake mani. Dont know what to do now???? Also running 93 octane always since I bought it in Aug.2017
Last edited by AlanTLS; 02-24-2019 at 04:58 PM.
#170
About a month ago I replaced the O2 & AF Sensors and oem cats with rv6 high flow cats. Also did a atlp v3-r jpipe at the same time, which deletes the 3rd cat.
I don’t know if it was more the O2 & AF sensors, the cats or all 3 together but so far (200+ miles later) I haven’t had any codes or misfires sine. And we just had our coldest days of the year here over the last few weeks. I was working on putting a thread together for all that but haven’t had time. I’m not on here much anymore unfortunately.
Previously after anything I replaced or did the misfire codes, rough idle at startup, would still come back within a week. Or as soon as it got cold out again.
So for me at least this worked and its been runnning great ever since. Sounds a lil better to
I don’t know if it was more the O2 & AF sensors, the cats or all 3 together but so far (200+ miles later) I haven’t had any codes or misfires sine. And we just had our coldest days of the year here over the last few weeks. I was working on putting a thread together for all that but haven’t had time. I’m not on here much anymore unfortunately.
Previously after anything I replaced or did the misfire codes, rough idle at startup, would still come back within a week. Or as soon as it got cold out again.
So for me at least this worked and its been runnning great ever since. Sounds a lil better to
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#171
New to this forum, and pretty new to my car, a 2008 Acura TL Type-S black on black, 6 speed, with factory A-Spec kit. Love the car, have wanted one forever. Bought this in hopes I could avoid working on it frequently, unlike my old Integra's. I have been having an issue with misfires, and cannot figure it out. Any help/insight appreciated!
Keep getting codes for multiple/random misfires, usually for all cylinders. Soon inspecting the coils, 3 were filled with oil (bad valve cover gaskets.) Replaced 3 of the coils, all 6 spark plugs with the correct NGK, valve cover gaskets, spark plug gaskets, and intake manifold gaskets. Misfire persisted approx. 300km later, with occasional flashing at a red light, which would become solid when moving. I then had timing inspected, a compression test, and valve adjustment done at the Acura dealer. Set me back more than I liked, but we were both confident this solved all my issues. Valves are slightmy suited, but still misfires. Replaced OFF valve, cleaned EGR passeges, still misfires. It only SEEMS to be at idle. You can feel a shaking in the chassis, especially when cold, and on the motor (my front mount is bad, fluid leaked). You can also hear a miss in the exhaust pipes, not a constant, but it is there. Any load, including the fans turning on and it seems to quit. Any advice on where to look next? Injectors? Compression test was mint and valves are adjusted. Thanks.
Keep getting codes for multiple/random misfires, usually for all cylinders. Soon inspecting the coils, 3 were filled with oil (bad valve cover gaskets.) Replaced 3 of the coils, all 6 spark plugs with the correct NGK, valve cover gaskets, spark plug gaskets, and intake manifold gaskets. Misfire persisted approx. 300km later, with occasional flashing at a red light, which would become solid when moving. I then had timing inspected, a compression test, and valve adjustment done at the Acura dealer. Set me back more than I liked, but we were both confident this solved all my issues. Valves are slightmy suited, but still misfires. Replaced OFF valve, cleaned EGR passeges, still misfires. It only SEEMS to be at idle. You can feel a shaking in the chassis, especially when cold, and on the motor (my front mount is bad, fluid leaked). You can also hear a miss in the exhaust pipes, not a constant, but it is there. Any load, including the fans turning on and it seems to quit. Any advice on where to look next? Injectors? Compression test was mint and valves are adjusted. Thanks.
#172
U guys gotta remember that another aspect of this is checking the carbon buildup in the intake valleys as well as the egr valves. Lastly, after you take care of this, it’s been addressed that it’s very easy to put intake manifold gasket on incorrectly, which leads to the egr port getting blocked from airflow by the gasket.
likely, by now, your v6s have significant carbon buildup in the egr ports that needs to be scraped out.
don’t gouge the metal btw
likely, by now, your v6s have significant carbon buildup in the egr ports that needs to be scraped out.
don’t gouge the metal btw