When the car (2003 TL Type S) was given to me, it had an obscene amount of vibration making its way into the cabin, like the car was going to shake itself apart. Changing the bad engine mounts took care of about 75% of it. However, there is still a good amount of engine vibration being felt. After doing some research, it looks like the OEM mounts used vacuum lines to help keep vibration down. The repair shop used "Duralast" mounts (yuck?). If those don't use vacuum lines, would that be the reason I still feel engine vibrations? If not, are there any other things I can check that could help make things run smoother?

The Check Engine Light doesn't come on (it does work when the car isn't started and the key is turned to the "on" position to show that all lights are working), so I'm guessing the cause of the vibration isn't serious enough to break things... but it still kinda bugs me. I remember the car wasn't completely smooth when my sister got it way back in 2003, and I understand that cars don't run like new after almost 20 years, but this is still seems to be more than what I think should be considered normal. Then again, I haven't driven any other 2nd Generation TLs.

 

I have a 2001 TL 3.2l with 231k miles and it is totally smooth running. I mean it runs just as well as my much newer and low-mileage Lincolns and Cadillac.

If it is not smooth, I would start looking into exactly why. I would do plugs, coils, adjust the valves and verify that everything on the intake side is nice and tight and leak-proof.

If ours did not run so well I would not have invested as much as I have already in it.

 

Thanks for guiding me in what to look at next. I guess I'll add coilpacks and plugs to the appointment for the timing belt change. Would these work? The listing says 3.2L and 3.5L V6s. I tried to search for Type S versions, but they don't come up.


Taking a look at the intake side of things, I changed the air filter. Wow, it was really bad. the entire "dirty side" was caked with dirt. I've never seen one as bad. Back in my day, "female owned/driven" was something put on classified ads to try to help sell a used car. I guess this one is a prime example of how that "feature" of a used car shouldn't hold any value. all the hoses I could see that connect to the intake manifold and throttle body feel tight and snug without holes. I guess the next steps would be to look at the EGR and PCV valves?

Would "Seafoam-ing" be a thing to do, in case there's a bunch of junk built up in the intake manifold and on the valves?

 

Yeah, doing a seafoam treatment can only help at this point.

These are the coils I used : https://www.rockauto.com/en/moreinfo...&pt=7060&jsn=7

I would most certainly say a valve adjustment is needed. If you do that you will be pulling the top intake off the engine to accomplish it, in which case I would get a set of felpro upper gaskets and plan on cleaning out the EGR passages in the upper intake manifold. Looking at the EGR valve isn't a bad idea and replacing the PCV valve is part of a "tune-up" so if you are doing the rest, do that as well. I would probably buy an extra PCV valve grommet and plan on replacing that when you do the valve.

I did all of this on ours and I would consider all of that "routine maintenance" at the age/mileage. I mean ours ran great and I STILL replaced the coils.

Doing the valve adjustment isn't a big deal. Overall I can honestly say that I can't really notice ours running much different at all after all was said and done. I will probably replace the PCV valve and blow out the lower passageway (all the upper manifold passages got cleaned when I had it off to do the valve adjustment) when I replace it. I have a slight miss/stumble on cold-startup that goes away within a minute or so (most of the time within 10-15 seconds) and it never had the slightest hint of a stumble when warm. It hasn;'t ever thrown a code and I have been told by many people that it is fairly normal for these engines to have a stumble on cold start and that they all smooth out when warmed up.

I still need to do the timing set (I have all the parts sitting in the garage) which includes the waterpump and a coolant change as well as all new belts/tensioners/pulleys and I even bought a brand new higher output alternator (the one used on the Odyssey I think) to swap on when I do it all.

 

I would start with the least invasive items...EGR system is pretty easy to inspect, if it's dirty then yes, plan to do the cleaning.

If you do clean, I would highly recommend replacing the gaskets as you have to remove the throttle body in order to get to it and it would be a shame to get everything back together again and discover there was a vacuum leak.

If EGR isn't obstructed or filled with loose carbon deposits, then try looking at the IACV; it gets gummed up and as a result will not respond a quickly as it needs to leading to rough idle.