Situation: 2002 TL-P, original owner, now at 102K. Timing belt done at 10 years, 70k. (I split the difference between 7 years and 105K on the timing belt since a failure is a blown engine.) Time to do the valves and also time to replace the spark plugs.

BUT, thinking about selling the car in the next year or two. Which could mean in 3 years since this is our workhorse car we drive everywhere.

So, when do you really need to do the plugs and valves? Especially the valves.

Car runs well and I haven't done the EGR cleaning yet. Replaced front and side engine mounts when doing the timing belt.

Transmission replaced by Acura in 2008. Approx 40K on the tranny now. One drain and fill with the new Honda fluid at 30K and no issues. Smooth as silk.

The reason this car is our workhorse is because it's so dependable (key in, star, go). And because the other is a BMW.

 

Spark plugs should be done now for sure. They are cheap enough. Top of Intake manifold and EGR cleaning a definite too. Valves..I Would say if they aren't noisy you should be ok. Others may think otherwise. Maine have never been done and I'm at 177k and they are quiet.

 

Yeah at 102K, put some quality fuel system cleaner in the next tank of gas. Once it's run out...... clean the TB intake, EGR passageways and IAC valve. Then use NGK's to replace the plugs, replace the air filter and pcv valve. Flush brake fluid and ps fluid with new.

Being the original owner, ya know if quality premium fuel was primarily used.....then the valve adjustment could probably be left go unless experiencing problems. In another year or two, should ya decide to keep your "workhorse" TL.....then consider the valve adjustment with the next T-belt service. Also, check the rear mount for wear and keep the ATF clean.

 

Valves usually will cause a subtle misfire around 150k miles, as the exhaust valves get tight. The intakes will loosen up slightly, but are rarely noisy enough to merit attention. As far as plugs go, I've seen them go over 200k miles with no symptoms. Years ago, I had a customer who meticulously maintained his cars, but only changed plugs when the fuel mileage dropped off. He was able to go 120-150k miles on conventional copper core plugs, with no precious metal electrodes. The plugs showed a LOT of wear, with the gap wearing to about 1/8". Ngk double platimum, or iridium plugs with a platinum side electrode show NO measurable wear at 100-120k. Some other companies plugs will show wear at these mileages, especially if the platinum pad falls off, which I've seen a few times.

 

Short Answer: YOU NEED TO ADJUST THEM.
Exhaust Valves to this point should have no gap at all which is far more dangerous than loose valves.





That explains it all, I feel your pain.

 

Thanks all. Since I do about 8K per year, I'll defer the valves for 2 years and keep the fluids clean as well as new plugs and the EGR system cleaning.

 

when you have the intake off to clean the egr system passages, its not much further to remove the valve covers ands take care of that critical adjusting job

Our hi tech ignition eats spark plugs, even the correct 8 dollar each ones are lucky to get a solid 70kmiles on them before showing wear on the electrode = reduced performance/spark generated

not driving many miles per trip, or per year, put wear of a different kind on the fluids and car

 

^ when I did my plugs at 90K there was no visible wear on them. They each looked normal and every one had the original fine point on them. This time I will check them if I have the car at 210K and change if needed. I do a lot of highway driving in my car at mostly constant speeds. Both cars are noted in the sig.

I am actually going to install the same type of plugs into the Subaru when I change them out in the spring and I am sure I will most likely never have to touch them again for the next 10 years or so. The iridium plugs hold up extremely well even in my other ride a vino 125 that has seem 25K miles at pretty much WOT.